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  • 1.
    Aalto, Anne
    et al.
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Sjoewall, Johanna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Klinisk immunologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Infektionskliniken i Östergötland.
    Davidsson, Leif
    Linköpings universitet, Institutionen för medicin och vård, Radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Forsberg, Pia
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Infektionsmedicin. Östergötlands Läns Landsting, Medicincentrum, Infektionskliniken i Östergötland.
    Smedby, Örjan
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Brain magnetic resonance imaging does not contribute to the diagnosis of chronic neuroborreliosis2007Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, nr 7, s. 755-762Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Borrelia infections, especially chronic neuroborreliosis ( NB), may cause considerable diagnostic problems. This diagnosis is based on symptoms and findings in the cerebrospinal fluid but is not always conclusive. Purpose: To evaluate brain magnetic resonance imaging ( MRI) in chronic NB, to compare the findings with healthy controls, and to correlate MRI findings with disease duration. Material and Methods: Sixteen well- characterized patients with chronic NB and 16 matched controls were examined in a 1.5T scanner with a standard head coil. T1- ( with and without gadolinium), T2-, and diffusion- weighted imaging plus fluid- attenuated inversion recovery ( FLAIR) imaging were used. Results: White matter lesions and lesions in the basal ganglia were seen in 12 patients and 10 controls ( no significant difference). Subependymal lesions were detected in patients down to the age of 25 and in the controls down to the age of 43. The number of lesions was correlated to age both in patients ( rho=0.83, P < 0.01) and in controls ( rho=0.61, P < 0.05), but not to the duration of disease. Most lesions were detected with FLAIR, but many also with T2- weighted imaging. Conclusion: A number of MRI findings were detected in patients with chronic NB, although the findings were unspecific when compared with matched controls and did not correlate with disease duration. However, subependymal lesions may constitute a potential finding in chronic NB.

  • 2.
    Bergkvist, Göran
    et al.
    Chonbuk National University.
    Sahlholm, Sten
    Linköpings universitet, Institutionen för nervsystem och rörelseorgan, Käkkirurgi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Rekonstruktionscentrum, Käkkliniken.
    Klintström, Eva
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Lindh, Christina
    Malmö University.
    Bone Density at Implant Sites and Its Relationship to Assessment of Bone Quality and Treatment Outcome2010Ingår i: INTERNATIONAL JOURNAL OF ORAL and MAXILLOFACIAL IMPLANTS, ISSN 0882-2786, Vol. 25, nr 2, s. 321-328Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To investigate the relationship between bone mineral density (BMD) before implant placement, implant stability measures at implant placement, and marginal bone loss of immediately loaded implants after 1 year in situ. Materials and Methods: Consecutively recruited patients received Straumann SLActive implants loaded with fixed provisional prostheses within 24 hours. BMD was measured from computed tomographic images before implant placement. Alveolar bone quality was assessed during surgery. Implant stability-both rotational and as measured with resonance frequency analysis- and marginal bone height were assessed at implant placement and after 1 year. The Pearson correlation coefficient was used to calculate correlations, and significance was considered when P andlt; .05. Results: Twenty-one patients received 137 implants (87 in maxillae and 50 in mandibles). BMD was significantly correlated with bone quality classification in both arches (P andlt; .001). Mean BMD was also significantly correlated with stability values (P andlt; .001). Mean marginal bone loss at implant surfaces differed, but not significantly, at the 1-year follow-up, regardless of BMD values (P = .086) and measured stability (rotational stability P = .34, resonance frequency analysis P = .43) at implant placement. Conclusion: Within the limits of this study, it can be concluded that computed tomographic examination can be used as a preoperative method to assess jawbone density before implant placement, since density values correlate with prevailing methods of measuring implant stability. However, in the short time perspective of 1 year, there were no differences in survival rates or changes in marginal bone level between implants placed in bone tissue of different density.

  • 3.
    Björnsson, Hanna
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Ortopedicentrum, Ortopedkliniken Linköping.
    Norlin, Rolf
    Örebro University Hospital.
    Knutsson, Anders
    Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Adolfsson, Lars
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Ortopedi och idrottsmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Ortopedicentrum, Ortopedkliniken Linköping.
    Fewer rotator cuff tears fifteen years after arthroscopic subacromial decompression2010Ingår i: Journal of shoulder and elbow surgery, ISSN 1058-2746, E-ISSN 1532-6500, Vol. 19, nr 1, s. 111-115Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: A successful clinical result is reported in 75% to 85% of impingement patients after arthroscopic subacromial decompression. The result is maintained over time, but few studies have investigated the integrity of the rotator cuff in these patients. Materials and methods: Using ultrasonography, we examined the integrity of the rotator cuff in 70 patients 15 years after arthroscopic subacromial decompression. All patients had an intact rotator cuff at the index procedure. Results: Tendons were still intact in 57 patients (82%), 10 (14%) had partial-thickness tears, and 3 (4%) had full-thickness tears. Discussion: The total number of 18% tears (partial and full thickness) in this study, including patients clinically diagnosed with subacromial impingement at a mean age of 60 years, is unexpectedly low compared with 40% degenerative tears reported in asymptomatic adults of the same age. Conclusion: Arthroscopic subacromial decompression seems to reduce the prevalence of rotator cuff tears in impingement patients. This appears attributable to elimination of extrinsic factors such as mechanical wear and bursitis. The potential effect of surgery on intrinsic cuff degeneration is unknown, but intrinsic factors may explain tears still developing despite decompression.

  • 4.
    Brismar, Torkel
    et al.
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Dahlström, Nils
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Edsborg, Nick
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Albiin, Nils
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Liver Vessel Enhancement by Gd-BOPTA and Gc-EOB-DTPA – a Comparison in Healthy Volunteers.2009Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 50, nr 7, s. 709-715Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: A thorough understanding of magnetic resonance (MR) contrast media dynamics makes it possible to choose the optimal contrast media for each investigation. Differences in visualizing hepatobiliary function between Gd-BOPTA and Gd-EOB-DTPA have previously been demonstrated, but less has been published regarding differences in liver vessel visualization.Purpose: To compare the liver vessel and liver parenchymal enhancement dynamics of Gd-BOPTA (MultiHance®) and Gd-EOB-DTPA (Primovist®). Material and Methods: The signal intensity of the liver parenchyma, the common hepatic artery, the middle hepatic vein, and a segmental branch of the right portal vein, was obtained in 10 healthy volunteers before contrast media administration, during arterial and portal venous phases, and 10, 20, 30, 40 and 130 minutes after intravenous contrast medium injection, but due to scanner limitations not during the hepatic venous phase. Results: Maximum enhancement of liver parenchyma was observed from the portal venous phase until 130 minutes after Gd-BOPTA administration and from 10 minutes to 40 minutes after Gd-EOB-DTPA. There was no difference in maximum enhancement of liver parenchyma between the two contrast media. When using Gd-BOPTA, the vascular contrast enhancement was still apparent 40 minutes after injection, but had vanished 10 minutes after Gd-EOB-DTPA injection. The maximum difference in signal intensity between the vessels and the liver parenchyma was significantly greater with Gd-BOPTA than with Gd-EOB-DTPA (p<0.0001). Conclusion: At the dosage used in this study Gd-BOPTA yields higher maximum enhancement of the hepatic artery, portal vein and middle hepatic vein during the arterial and the portal venous phase and during the delayed phases than Gd-EOB-DTPA does, whereas there is no difference in liver parenchymal enhancement between the two contrast agents.

  • 5.
    Dahlqvist Leinhard, Olof
    et al.
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Dahlström, Nils
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Brismar, T
    Sandström, Per
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Kirurgi. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Kirurgiska kliniken i Östergötland med verksamhet i Linköping, Norrköping och Motala.
    Kihlberg, Johan
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Smedby, Örjan
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Avdelningen för radiologi US. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    A liver function test based on measurement of liver-specific contrast agent uptake2008Ingår i: Proceedings 16th Scientific meeting, ISMRM,2008, 2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

      

  • 6.
    Dahlqvist Leinhard, Olof
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Johansson, Andreas
    Linköpings universitet, Institutionen för medicinsk teknik, Medicinsk informatik. Linköpings universitet, Tekniska högskolan.
    Rydell, Joakim
    Linköpings universitet, Institutionen för medicinsk teknik, Medicinsk informatik. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Kihlberg, Johan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Nyström, Fredrik H.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Borga, Magnus
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicinsk teknik, Medicinsk informatik. Linköpings universitet, Tekniska högskolan.
    Quantification of abdominal fat accumulation during hyperalimentation using MRI2009Ingår i: Proceedings of the ISMRM Annual Meeting (ISMRM'09), 2009, Berkeley, CA, USA: International Society for Magnetic Resonance in Medicine , 2009, s. 206-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    There is an increasing demand for imaging methods that can be used for automatic, accurate and quantitative determination of the amounts of abdominal fat. Such methods are important as they will allow the evaluation of some of the risk factors underlying the ’metabolic syndrome’. The metabolic syndrome is becoming common in large parts of the world, and it appears that a dominant risk factor for developing this syndrome is abdominal obesity. Subjects that are afflicted with the metabolic syndrome are exposed to a high risk for developing a large range of diseases such as type 2 diabetes, cardiac failure, and stroke. The aim of this work

  • 7.
    Dahlström, Nils
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Magnetic Resonance Imaging of the Hepatobiliary System Using Hepatocyte-Specific Contrast Media2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    There are two Gadolinium-based liver-specific contrast media for Magnetic Resonance Imaging on the market, Gd-BOPTA (MultiHance®, Bracco Imaging, Milan, Italy) and Gd-EOB-DTPA (Primovist®, Bayer Schering Pharma, Berlin, Germany). The aim of this study in two parts was to evaluate the dynamics of biliary, parenchymal and vascular enhancement using these contrast media in healthy subjects. Ten healthy volunteers were examined in a 1.5 T magnetic resonance system using three-dimensional Volumetric Interpolated Breath-Hold (VIBE) sequences for dynamic imaging with both contrast media – at two different occasions – until five hours after injection. The doses given were 0.025 mmol/kg for Gd-EOB-DTPA and 0.1 mmol/kg for Gd-BOPTA. The enhancement over time of the common biliary duct in contrast to the liver parenchyma was analyzed in the first study. This was followed by a study of the image contrasts of the hepatic artery, portal vein and middle hepatic vein versus the liver parenchyma.While Gd-EOB-DTPA gave an earlier and more prolonged enhancement of the biliary duct, Gd-BOPTA achieved higher image contrast for all vessels studied, during the arterial and portal venous phases. There was no significant difference in the maximal enhancement obtained in the liver parenchyma.At the obtained time-points and at the dosage used, the high contrast between the common biliary duct and liver parenchyma had an earlier onset and longer duration for Gd-EOB-DTPA, while Gd-BOPTA achieved higher maximal enhancement of the hepatic artery, portal vein and middle hepatic vein than Gd-EOB-DTPA. Diseases of the liver and biliary system may affect the vasculature, parenchyma, biliary excretion or a combination of these. The clinical context regarding the relative importance of vascular, hepatic parenchymal and biliary processes should determine the choice of contrast media for each patient and examination.

     

    Delarbeten
    1. Contrast-enhanced magnetic resonance cholangiography with Gd-BOPTA and Gd-EOB-DTPA in healthy subjects
    Öppna denna publikation i ny flik eller fönster >>Contrast-enhanced magnetic resonance cholangiography with Gd-BOPTA and Gd-EOB-DTPA in healthy subjects
    Visa övriga...
    2007 (Engelska)Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, nr 4, s. 362-368Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    PURPOSE: To evaluate the biliary enhancement dynamics of the two gadolinium chelates Gd-BOPTA (MultiHance) and Gd-EOB-DTPA (Primovist) in normal healthy subjects. MATERIAL AND METHODS: Ten healthy volunteers were evaluated with both agents by magnetic resonance (MR) imaging at 1.5T using a breath-hold gradient-echo T1-weighted VIBE sequence. The relative signal intensity (SI) differences between the common hepatic duct (CHD) and liver parenchyma were measured before and 10, 20, 30, 40, 130, 240, and 300 min after contrast medium injection. RESULTS: Biliary enhancement was obvious 10 min post-injection for Gd-EOB-DTPA and was noted at 20 min for Gd-BOPTA. At 40 min delay, Gd-BOPTA reached its peak biliary enhancement, but at neither 30 nor 40 min delay was there any significant difference compared with that of Gd-EOB-DTPA. At later delays, the contrast between CHD and liver continued to increase for Gd-EOB-DTPA, whereas it decreased for Gd-BOPTA. CONCLUSION: The earlier onset and longer duration of a high contrast between CHD and liver for Gd-EOB-DTPA facilitates examination of hepatobiliary excretion. Therefore, Gd-EOB-DTPA may provide adequate hepatobiliary imaging within a shorter time span than Gd-BOPTA and facilitate scheduling at the MR unit. Further studies in patients are required to compare the imaging advantages of Gd-EOB-DTPA and Gd-BOPTA in clinical practice.

    Ort, förlag, år, upplaga, sidor
    Informa Healthcare, 2007
    Nyckelord
    Bile ducts; biliary; comparative studies; intravenous contrast agents; liver; MR imaging
    Nationell ämneskategori
    Radiologi och bildbehandling
    Identifikatorer
    urn:nbn:se:liu:diva-17916 (URN)10.1080/02841850701196922 (DOI)000246782700002 ()
    Anmärkning

    This is an electronic version of an article published in: Nils Dahlström, Anders Persson, Nils Albiin, Örjan Smedby and Torkel Brismar, Contrast-enhanced magnetic resonance cholangiography with Gd-BOPTA and Gd-EOB-DTPA in healthy subjects, 2007, Acta Radiologica, (48), 4, 362-368. Acta Radiologica is available online at informaworldTM: http://dx.doi.org/10.1080/02841850701196922 Copyright: Taylor & Francis http://www.tandf.co.uk/journals/default.asp

    Tillgänglig från: 2009-04-24 Skapad: 2009-04-24 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    2. Liver Vessel Enhancement by Gd-BOPTA and Gc-EOB-DTPA – a Comparison in Healthy Volunteers.
    Öppna denna publikation i ny flik eller fönster >>Liver Vessel Enhancement by Gd-BOPTA and Gc-EOB-DTPA – a Comparison in Healthy Volunteers.
    Visa övriga...
    2009 (Engelska)Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 50, nr 7, s. 709-715Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: A thorough understanding of magnetic resonance (MR) contrast media dynamics makes it possible to choose the optimal contrast media for each investigation. Differences in visualizing hepatobiliary function between Gd-BOPTA and Gd-EOB-DTPA have previously been demonstrated, but less has been published regarding differences in liver vessel visualization.Purpose: To compare the liver vessel and liver parenchymal enhancement dynamics of Gd-BOPTA (MultiHance®) and Gd-EOB-DTPA (Primovist®). Material and Methods: The signal intensity of the liver parenchyma, the common hepatic artery, the middle hepatic vein, and a segmental branch of the right portal vein, was obtained in 10 healthy volunteers before contrast media administration, during arterial and portal venous phases, and 10, 20, 30, 40 and 130 minutes after intravenous contrast medium injection, but due to scanner limitations not during the hepatic venous phase. Results: Maximum enhancement of liver parenchyma was observed from the portal venous phase until 130 minutes after Gd-BOPTA administration and from 10 minutes to 40 minutes after Gd-EOB-DTPA. There was no difference in maximum enhancement of liver parenchyma between the two contrast media. When using Gd-BOPTA, the vascular contrast enhancement was still apparent 40 minutes after injection, but had vanished 10 minutes after Gd-EOB-DTPA injection. The maximum difference in signal intensity between the vessels and the liver parenchyma was significantly greater with Gd-BOPTA than with Gd-EOB-DTPA (p<0.0001). Conclusion: At the dosage used in this study Gd-BOPTA yields higher maximum enhancement of the hepatic artery, portal vein and middle hepatic vein during the arterial and the portal venous phase and during the delayed phases than Gd-EOB-DTPA does, whereas there is no difference in liver parenchymal enhancement between the two contrast agents.

    Ort, förlag, år, upplaga, sidor
    Informa Healthcare, 2009
    Nyckelord
    Gd-BOPTA, Gd-EOB-DTPA, MRI, liver, contrast dynamics
    Nationell ämneskategori
    Radiologi och bildbehandling
    Identifikatorer
    urn:nbn:se:liu:diva-17917 (URN)10.1080/02841850903055603 (DOI)000270458500002 ()
    Tillgänglig från: 2009-04-24 Skapad: 2009-04-24 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
  • 8.
    Dahlström, Nils
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Albiin, Nils
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Brismar, Torkel
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Contrast-enhanced magnetic resonance cholangiography with Gd-BOPTA and Gd-EOB-DTPA in healthy subjects2007Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, nr 4, s. 362-368Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To evaluate the biliary enhancement dynamics of the two gadolinium chelates Gd-BOPTA (MultiHance) and Gd-EOB-DTPA (Primovist) in normal healthy subjects. MATERIAL AND METHODS: Ten healthy volunteers were evaluated with both agents by magnetic resonance (MR) imaging at 1.5T using a breath-hold gradient-echo T1-weighted VIBE sequence. The relative signal intensity (SI) differences between the common hepatic duct (CHD) and liver parenchyma were measured before and 10, 20, 30, 40, 130, 240, and 300 min after contrast medium injection. RESULTS: Biliary enhancement was obvious 10 min post-injection for Gd-EOB-DTPA and was noted at 20 min for Gd-BOPTA. At 40 min delay, Gd-BOPTA reached its peak biliary enhancement, but at neither 30 nor 40 min delay was there any significant difference compared with that of Gd-EOB-DTPA. At later delays, the contrast between CHD and liver continued to increase for Gd-EOB-DTPA, whereas it decreased for Gd-BOPTA. CONCLUSION: The earlier onset and longer duration of a high contrast between CHD and liver for Gd-EOB-DTPA facilitates examination of hepatobiliary excretion. Therefore, Gd-EOB-DTPA may provide adequate hepatobiliary imaging within a shorter time span than Gd-BOPTA and facilitate scheduling at the MR unit. Further studies in patients are required to compare the imaging advantages of Gd-EOB-DTPA and Gd-BOPTA in clinical practice.

  • 9.
    Duffy, Stephen W.
    et al.
    Queen Mary University of London.
    Tabar, Laszlo
    Central Hospital, Falun.
    Olsen, Anne Helene
    Queen Mary University of London.
    Vitak, Bedrich
    Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Allgood, Prue C.
    Queen Mary University of London.
    Chen, Tony H. H.
    National Taiwan University.
    M. F. Yen, Amy
    National Taiwan University.
    Smith, Robert A.
    American Cancer Society, Atlanta.
    Absolute numbers of lives saved and overdiagnosis in breast cancer screening, from a randomized trial and from the Breast Screening Programme in England2010Ingår i: Journal of Medical Screening, ISSN 0969-1413, E-ISSN 1475-5793, Vol. 17, nr 1, s. 25-30Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives To estimate the absolute numbers of breast cancer deaths prevented and the absolute numbers of tumours overdiagnosed in mammographic screening for breast cancer at ages 50-69 years. Setting The Swedish Two-County randomized trial of mammographic screening for breast cancer, and the UK Breast Screening Programme in England, ages 50-69 years. Methods We estimated the absolute numbers of deaths avoided and additional cases diagnosed in the study group (active study population) of the Swedish Two-County Trial, by comparison with the control group (passive study population). We estimated the same quantities for the mortality and incidence rates in England (1974-2004 and 1974-2003, respectively). We used Poisson regression for statistical inference. Results A substantial and significant reduction in breast cancer mortality was associated with screening in both the Two-County Trial (Pless than0.001) and the screening programme in England (Pless than0.001). The absolute benefits were estimated as 8.8 and 5.7 breast cancer deaths prevented per 1000 women screened for 20 years starting at age 50 from the Two-County Trial and screening programme in England, respectively. The corresponding estimated numbers of cases overdiagnosed per 1000 women screened for 20 years were, respectively, 4.3 and 2.3 per 1000. Conclusions The benefit of mammographic screening in terms of lives saved is greater in absolute terms than the harm in terms of overdiagnosis. Between 2 and 2.5 lives are saved for every overdiagnosed case.

  • 10.
    Engellau, Lena
    et al.
    Department of Radiology, Lund University Hospital, Lund, Sweden.
    Albrechtsson, U.
    Department of Radiology, Lund University Hospital, Lund, Sweden.
    Dahlström, Nils
    Department of Radiology, Hudiksvall Hospital, Hudiksvall Sweden.
    Norgren, L.
    Department of Vascular Diseases, Lund University, Malmo University Hospital, Malmo, Sweden.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Larsson, E.-M.
    Department of Radiology, Lund University Hospital, Lund, Sweden.
    Measurements before endovascular repair of abdominal aortic aneurysms: MR imaging with MRA vs. angiography and CT2003Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 44, nr 2, s. 177-184Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: 1) To compare measurements obtained with MR imaging (MRI)/contrast-enhanced MR angiography (CE MRA) with measurements obtained with angiography (DSA) and CT, for stent-graft sizing of abdominal aortic aneurysms (AAA). 2) To compare MRA measurements obtained with the two post processing techniques MIP (maximum intensity projection) and VRT (3D volume rendering technique).

    Material and Methods: The prospective study included 20 consecutive patients with AAA identified by DSA and CT as suitable for endovascular repair. For the study, MRI/CE MRA was performed. Five measurement variables for stent-graft sizing were chosen. Comparisons were made between MRI/CE MRA, DSA and CT, and between observers. Comparisons were also made between MIP and VRT.

    Results: Significantly shorter lengths were obtained with MRA-MIP than with DSA. Three out of six diameter measurements were significantly smaller on MRI/CE MRA than on DSA and CT. No significant differences were found between the observers. One diameter measurement was significantly smaller on MIP than on VRT, while the other measurements showed no significant differences.

    Conclusion: The length measurements obtained with MRA-MIP were probably more correct than those with DSA. For more reliable diameter measurements with CE MRA, improvements of the technique, including VRT reconstructions and a standardized determination of the vessel boundaries, are needed.

  • 11.
    Engström, Maria
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Karlsson, Thomas
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Filosofiska fakulteten.
    An fMRi investigation of mental effort in a complex working memory task2010Ingår i: 16th Annual Meeting of the Organization for Human Brain Mapping, Barcelona 2010: Abstract No 1116, 2010Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

     

    A fundamental component of attention and working memory is the ability to allocate sufficient amount of mental resources to ongoing activity. Despite the fact that ’effort’ is a key ingredient to current theories about attention and memory, little is known about the brain’s regulation of cognitive effort. In this fMRI study, we employed the momentous Daneman reading span task (Daneman & Carpenter, 1980) to induce cognitive effort. We have previously used complex working memory tasks to study deficits with respect to effortful processing in patients with sleep disorders (Engström, et al., 2009). We have noted profound involvement of the anterior cingulate cortex in relation to cognitive effort. We now wish to corroborate this finding in a larger group of healthy participants.

     

     

  • 12.
    Engström, Maria
    et al.
    Linköpings universitet. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Karlsson, Thomas
    Linköpings universitet. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Disorganised working memory functional connectivity in periodic hypersomnia2010Ingår i: 16th Annual Meeting of the Organization for Human Brain Mapping, Barcelona 2010: 16th Annual Meeting of the Organization for Human Brain Mapping, Abstract No 1771, 2010Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The Kleine–Levin Syndrome (KLS) is a rare but relatively well-defined disorder characterised by excessive sleep periods (periodic hypersomnia) associated with cognitive deficits and behavioural disturbances such as binge eating and hypersexuality [1]. The etiology of KLS is unknown and several neuroimagning methods have been applied to investigate the neural corrlates to KLS. A functional Magnetic Resonance Imaging (fMRI) study by us implicated hyperactivity in the thalamus and hypoactivity in the anterior cingulate cortex and the right anterior insula in a working memory task [2], which imply the involvement of a recently proposed anterior cingulate-insular control network in KLS [3]. As we expected less coherent organisation in KLS, we compared the connectivity of the anterior cingulate-insular and thalamic (AIT) network and the well-known, working memory-related, dorsal attention network (involving the dorsolateral prefrontal cortex and parietal areas) between KLS and controls.

  • 13.
    Engström, Maria
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Ragnehed, Mattias
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    On the Advantage of Data Driven Analysis in Aphasic Patients with Severe Language Latncy2010Konferensbidrag (Övrigt vetenskapligt)
  • 14.
    Engström, Maria
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Söderfeldt, Birgitta
    Karolinska institutet, Stockholm.
    Brain Activation During Compassion Meditation: A Case Study2010Ingår i: Journal of Alternative and Complementary Medicine, ISSN 1075-5535, E-ISSN 1557-7708, Vol. 16, nr 5, s. 597-599Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives: B.L. is a Tibetan Buddhist with many years of compassion meditation practice. During meditation B.L. uses a technique to generate a feeling of love and compassion while reciting a mantra. The aim of the present study was to investigate the neural correlates of compassion meditation in 1 experienced meditator.

    Methods: B.L. was examined by functional magnetic resonance imaging during compassion meditation, applying a paradigm with meditation and word repetition blocks.

    Results: The most significant finding was the activation in the left medial prefrontal cortex extending to the anterior cingulate gyrus. Other significant loci of activation were observed in the right caudate body extending to the right insula and in the left midbrain close to the hypothalamus.

    Conclusions: The results in this study are in concordance with the hypothesis that compassion meditation is accompanied by activation in brain areas involved with empathy as well as with happy and pleasant feelings (i.e., the left medial prefrontal cortex and the anterior cingulate gyrus).

  • 15.
    Engström, Maria
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Vigren, Patrick
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Neurologi.
    Karlsson, Thomas
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Landtblom, Anne-Marie
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Neurologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Neurologiska kliniken. Östergötlands Läns Landsting, Närsjukvården i västra Östergötland, Medicinska specialistkliniken . Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Working Memory in 8 Kleine-Levin Syndrome Patients: An fMRI Study2009Ingår i: SLEEP, ISSN 0161-8105, Vol. 32, nr 5, s. 681-688Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Study Objectives: The objectives of this study were to investigate possible neuropathology behind the Kleine-Levin Syndrome (KLS), a severe form of hypersomnia with onset during adolescence.

    Design: Functional magnetic resonance imaging (fMRI) applying a verbal working memory task was used in conjunction with a paper-and-pencil version of the task. Participants: Eight patients with KLS and 12 healthy volunteers participated in the study.

    Results: The results revealed a pattern of increased thalamic activity and reduced frontal activity (involving the anterior cingulate and adjacent prefrontal cortex) while performing a reading span task.

    Discussion: This finding may explain the clinical symptoms observed in KLS, in that the thalamus is known to be involved in the control of sleep. Given the increasing access to fMRI, this investigation may aid clinicians in the diagnosis of patients suffering from severe forms of hypersomnia.

  • 16.
    Eriksson, Per
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Internmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Njurmedicinska kliniken US.
    Mohammed, Ahmed Abdulilah
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    De Geer, Jakob
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Kihlberg, Johan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Granerus, Göran
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Hjärtcentrum, Fysiologiska kliniken.
    Nyström, Fredrik
    Linköpings universitet, Institutionen för medicin och hälsa, Internmedicin. Linköpings universitet, Hälsouniversitetet.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Non-invasive investigations of potential renal artery stenosis in renal insufficiency2010Ingår i: Nephrology, Dialysis and Transplantation, ISSN 0931-0509, E-ISSN 1460-2385, Vol. 25, nr 11, s. 3607-3614Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background. The diagnostic value of non-invasive methods for diagnosing renal artery stenosis in patients with renal insufficiency is incompletely known.

    Methods. Forty-seven consecutive patients with moderately impaired renal function and a clinical suspicion of renal artery stenosis were investigated with computed tomography angiography (CTA), gadolinium-enhanced magnetic resonance angiography (MRA), contrast-enhanced Doppler ultrasound and captopril renography. The primary reference standard was stenosis reducing the vessel diameter by at least 50% on CTA, and an alternative reference standard (‘morphological and functional stenosis’) was defined as at least 50% diameter reduction on CTA or MRA, combined with a positive finding from ultrasound or captopril renography.

    Results. The frequency of positive findings, calculated on the basis of individual patients, was 70% for CTA, 60% for MRA, 53% for ultrasound and 30% for captopril renography. Counting kidneys rather than patients, corresponding frequencies were 53%, 41%, 29% and 15%, respectively. In relation to the CTA standard, the sensitivity (and specificity) at the patient level was 0.81 (0.79) for MRA, 0.70 (0.89) for ultrasound and 0.42 (1.00) for captopril renography, and at the kidney level 0.76 (0.82), 0.53 (0.81) and 0.30 (0.86), respectively. Relative to the alternative reference standard, corresponding values at the patient level were 1.00 (0.62) for CTA, 0.90 (0.69) for MRA, 0.91 (1.00) for ultrasound and 0.67 (1.00) for captopril renography, and at the kidney level 0.96 (0.76), 0.85 (0.79), 0.71 (0.97) and 0.50 (0.97), respectively.

    Conclusions. CTA and MRA are superior to ultrasound and captopril renography at diagnosing morphological stenosis, but ultrasound may be useful as a screening method and captopril renography for verifying renin-dependent hypertension.

  • 17.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Aids to Radiological Differential Diagnosis2009Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 50, nr 6, s. 701-701Artikel, recension (Refereegranskat)
  • 18.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Traditionell radiologi av hjärtat - mer än bara kranskärl!: Röntgen av sviktpatienten - strålande metod?2009Konferensbidrag (Övrigt vetenskapligt)
  • 19.
    Fägerstam, Patrik
    et al.
    Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Institutionen för medicin och hälsa, Farmakologi. Linköpings universitet, Hälsouniversitetet.
    Östberg, Anna Karin
    Linköpings universitet, Institutionen för medicin och hälsa, Farmakologi. Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Eriksson, Andreas
    Linköpings universitet, Institutionen för medicin och hälsa, Farmakologi. Linköpings universitet, Hälsouniversitetet.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Whiss, Per
    Linköpings universitet, Institutionen för medicin och hälsa, Farmakologi. Linköpings universitet, Hälsouniversitetet.
    Similar inhibition of platelet adhesion, P-selectin expression and plasma coagulation by ioversol, iodixanol and ioxaglate2010Ingår i: The British Journal of Radiology, ISSN 0007-1285, Vol. 83, nr 989, s. 401-410Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contrast media (CM) are reported to possess both pro-thrombotic and anticoagulant properties. The mechanisms are not clearly understood and early reports are contradictory. To study the effects of CM on haemostasis, we analysed the ex vivo effects of ioversol and iodixanol on platelet adhesion and P-selectin expression, and the in vitro effects of ioversol, iodixanol and ioxaglate on platelet adhesion, P-selectin expression and plasma coagulation. A novel enzymatic assay was used to measure platelet adhesion to protein surfaces and an enzyme-linked immunosorbent assay was used to measure platelet P-selectin surface expression. Pro-thrombin time (PT) and activated partial thromboplastin time (APTT) were used to measure plasma coagulation. The ex vivo study consisted of blood from 27 outpatients administered ioversol and 9 patients administered iodixanol intravenously. Samples were collected before and 5 min after CM administration. Healthy donors were used for the in vitro studies on the effects of CM. The ex vivo study showed significantly (p<0.05) decreased platelet adhesion and P-selectin expression after administration of ioversol and iodixanol. Adhesion was more affected than P-selectin expression. The in vitro study showed that ioversol, iodixanol and ioaxaglate significantly (p<0.05) and dose dependently (beginning at 3 mg ml(-1)) decreased platelet adhesion and P-selectin expression. APTT and PT were significantly (p<0.01) prolonged at concentrations of 10 mg ml(-1) and 30 mg ml(-1), respectively. In conclusion, ioversol, iodixanol and ioxaglate inhibit platelet adhesion and P-selectin expression, as well as plasma coagulation. Platelets are more sensitive in relation to the inhibiting effect on plasma coagulation.

  • 20.
    Gholami, S
    et al.
    Stanford University.
    Sarwal, M M
    Stanford University.
    Ringertz, Hans G
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Barth, R A
    Stanford University.
    Balise, R R
    Stanford University.
    Salvatierra, O
    Stanford University.
    Standardizing resistive indices in healthy pediatric transplant recipients of adult-sized kidneys2010Ingår i: Pediatric Transplantation, ISSN 1397-3142, E-ISSN 1399-3046, Vol. 14, nr 1, s. 126-131Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Small pediatric recipients of an adult-sized kidney have insufficient renal blood flow early after transplantation, with secondary chronic hypoperfusion and irreversible histological damage of the tubulo-interstitial compartment. It is unknown whether this is reflected by renal resistive indices. We measured renal graft resistive indices and volumes of 47 healthy pediatric kidney transplant recipients of an adult-sized kidney in a prospective study for six months post-transplant. A total of 205 measurements were performed. The smallest recipients (BSA </=0.75 m(2)) had higher resistive indices compared to recipients with a BSA between 0.75 and 1.5 m(2) (p < 0.0001) and to recipients with a BSA >/= 1.5 m(2) (p < 0.0001). Resistive indices increased during the first six months in the smallest recipients (p = 0.02), but not in the two larger recipient groups (BSA 0.75-1.5 m(2) and >/=1.5 m(2)). All three BSA groups showed a reduction in renal volume after transplantation, with the greatest reduction occurring in the smallest recipients. In conclusion, renal transplant resistive indices reflect pediatric recipient BSA dependency. The higher resistance to intra-renal vascular flow and significant decrease in renal volume in the smallest group likely reflect accommodation of the size discrepant transplanted adult-sized kidney to the smaller pediatric recipient vasculature with associated lower renal artery flow.

  • 21.
    Gimm, Oliver
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Kirurgiska kliniken i Östergötland med verksamhet i Linköping, Norrköping och Motala.
    Juhlin, Claes
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Kirurgi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Kirurgiska kliniken i Östergötland med verksamhet i Linköping, Norrköping och Motala.
    Morales, Olallo
    Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Dual-Energy Computed Tomography Localizes Ectopic Parathyroid Adenoma2010Ingår i: The Journal of Clinical Endocrinology & Metabolism, ISSN 0021-972X, Vol. 95, nr 7, s. 3092-3093Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dual-energy computed tomography (DECT) can acquire two datasets showing different attenuation levels allowing collectionof additional information about the elementary chemical compositionof the scanned material. Color can then be assigned accordingto the 80- and 140-kV computed tomography (CT) values to obtaina color-mapped, dual-energy image. DECT has been used extensivelyin our department in postmortem CT with excellent results (1).One of the advantages of DECT is that iodine contrast uptakein soft tissue can be quantified. We were wondering about itsability to localize parathyroid adenomas (PAs).

  • 22.
    Hallberg, Inger
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet.
    Bachrach-Lindström, Margareta
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet.
    Hammerby, Staffan
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Toss, Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Internmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Endokrin- och magtarmmedicinska kliniken.
    Ek, Anna-Christina
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Akutkliniken.
    Health-related quality of life after vertebral or hip fracture: a seven-year follow-up study2009Ingår i: BMC Musculoskeletal Disorders, ISSN 1471-2474, E-ISSN 1471-2474, Vol. 10, nr 135Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    The negative impact of vertebral and hip low-energy fractures on health-related quality-of-life (HRQOL) has been demonstrated previously, but few prospective long-term follow-up studies have been conducted. This study aims to (i) investigate the changes and long-term impact of vertebral or hip fracture and between fracture groups on HRQOL in postmenopausal women prospectively between two and seven years after the inclusion fracture, (ii) compare HRQOL results between fracture and reference groups and (iii) study the relationship between HRQOL and physical performance, spinal deformity index and bone mineral density at seven-year follow-up.

    Methods

    Ninety-one women examined two years after a low-energy vertebral or hip fracture were invited to a new examination seven years after the diagnosis. HRQOL was examined using the SF-36 questionnaire and was compared with an age and sex-matched reference group. Physical function was assessed using tests and questionnaires. Bone mineral density was measured. Radiographs of the spine were evaluated using the visual semiquantitative technique. A longitudinal and cross-sectional design was used in this study. Statistical analyses included descriptive statistics, Student’s t-tests, ANCOVA, and partial correlation.

    Results

    Sixty-seven women participated. In the 42 women (mean age 75.8, SD 4.7) with vertebral fracture as inclusion fracture, bodily pain had deteriorated between two and seven years and might be explained by new fracture. Remaining pronounced reduction of HRQOL was seen in all domains except general health and mental health at seven-year follow-up in women with vertebral fractures compared to the reference group (p<0.05). All 25 women (mean age 75.0, SD 4.7) with hip fracture as inclusion fracture had no significant changes in HRQOL between two and seven years and did not differ from the reference group regarding HRQOL after seven years. The vertebral group had significantly lower values for bodily pain, vitality, role-emotional function and mental health compared to the hip group. HRQOL showed a positive relationship between physical activity, static balance and handgrip strength.

    Conclusions

    The long-term reduction of HRQOL in women with vertebral fracture emerged clearly in this study. The relationships between HRQOL and physical performance in women with vertebral and hip fracture raise questions for more research.

  • 23.
    Hansson, Thomas
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Hand och plastikkirurgi. Linköpings universitet, Hälsouniversitetet.
    Nyman, Torbjörn
    Östergötlands Läns Landsting, Rekonstruktionscentrum, Hand- och plastikkirurgiska kliniken US.
    Björkman, Anders
    Malmö University Hospital.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Nylander, Lotta
    Östergötlands Läns Landsting, Rekonstruktionscentrum, Hand- och plastikkirurgiska kliniken US.
    Rosén, Birgitta
    Malmö University Hospital.
    Lundborg, Göran
    Malmö University Hospital.
    Sights of touching activates the somatosensory cortex in humans.2009Ingår i: Scandinavian journal of plastic and reconstructive surgery and hand surgery / Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi, ISSN 1651-2073, Vol. 43, nr 5, s. 267-269Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report our observations of cross-modal interactions between sight and touch using functional magnetic resonance imaging (fMRI). Experiments were devised to show that sight and touch are linked in a cross-modal arrangement, and two separate experiments were done in an MRI scanner. In the first, the subject's right hand was stimulated with a brush; in the second, a video sequence was presented to the subject inside the scanner through video goggles in visual three-dimensional stereo, showing one brushstroke every second on a hand in the same manner as the subject had just previously experienced. The result was that both the primary and the secondary somatosensory cortexes were activated in the participants when the hands were touched, and when the subjects saw only a hand being touched in the same manner. The results indicated cross-modal links between sight and touch of the hand in humans.

  • 24.
    Holmberg, L
    et al.
    Kings College London.
    Duffy, S W
    Wolfson Institute for Preventative Medicine.
    Yen, A M F
    Wolfson Institute for Preventative Medicine.
    Tabar, L
    Uppsala University.
    Vitak, B
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Nystrom, L
    Umea University.
    Frisell, J
    Karolinska Institute.
    Differences in endpoints between the Swedish W-E (two county) trial of mammographic screening and the Swedish overview: methodological consequences2009Ingår i: JOURNAL OF MEDICAL SCREENING, ISSN 0969-1413, Vol. 16, nr 2, s. 73-80Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives To characterize and quantify the differences in the number of cases and breast cancer deaths in the Swedish W-E Trial compared with the Swedish Overview Committee (OVC) summaries and to study methodological issues related to trials in secondary prevention. Setting The study population of the W-E Trial of mammography screening was included in the first (W and E county) and the second (E-county) OVC summary of all Swedish randomized mammography screening trials. The OVC and the W-E Trial used different criteria for case definition and causes of death determination. Method A Review Committee compared the original data files from Wand E county and the first and second OVC. The reason for a discrepancy was determined individually for all non-concordant cases or breast cancer deaths. Results Of the 2615 cases included by the W-E Trial or the OVC, there were 478 (18%) disagreements. Of the disagreements 82% were due to inclusion/exclusion criteria, and 18% to disagreement with respect to cause of death or vital status at ascertainment. For E-County, the OVC inclusion rules and register based determination of cause of death (second OVC) rather than individual case review (W-E Trial and 1st OVC) resulted in a reduction of the estimate of the effect of screening, but for W-County the difference between the original trial and the OVC was modest. Conclusions The conclusion that invitation to mammography screening reduces breast cancer mortality remains robust. Disagreements were mainly due to study design issues, while disagreements about cause of death were a minority. When secondary research does not adhere to the protocols of the primary research projects, the consequences of such design differences should be investigated and reported. Register linkage of trials can add follow-up information. The precision of trials with modest size is enhanced by individual monitoring of case status and outcome status such as determination of cause of death.

  • 25.
    Jaworski, J
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Tisell, Anders
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Landtblom, Anne-Marie
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Neurologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i västra Östergötland, Medicinska specialistkliniken .
    Treatment with glatiramer acetate (Copaxone (R)) prevents neurodegeneration in patients with multiple sclerosis2009Ingår i: in MULTIPLE SCLEROSIS, vol 15, issue 9, 2009, Vol. 15, nr 9, s. S140-S141Konferensbidrag (Refereegranskat)
    Abstract [en]

    n/a

  • 26.
    Kihlberg, Johan
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Engvall, Jan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Fysiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Hjärtcentrum, Fysiologiska kliniken.
    Maret, Eva
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet.
    Warntjes, Marcel
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Hjärtcentrum, Fysiologiska kliniken.
    Rommel, Franz
    Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Hematologiska kliniken US.
    Ackumulering av överskottsjärn kan bestämmas med MR2009Ingår i: Ackumulering av överskottsjärn kan bestämmas med MR, 2009Konferensbidrag (Refereegranskat)
    Abstract [sv]

    Järnöverskott kan vara toxiskt i kroppen. Järnöverskott ses fr a efter multipla blodtransfusioner vid vissa blodsjukdomar. Internationellt är den vanligaste orsaken thalassemi. Antalet patienter med denna problematik är i Sverige ännu begränsat. Järnöverskott kan leda till allvarlig, svårbehandlad hjärtsvikt man kan behandlas med chelaterande perorala läkemedel och styrs då i allmänhet utifrån ferritin/s. Vår hypotes var att överensstämmelsen mellan järnöverskott och transferrin är låg, att järnöverskott bättre karaktäriseras med MR som också kan differentiera mellan järnöverskott i  hjärta respektive lever.

  • 27.
    Kihlberg, Johan
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Klintström, Eva
    Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Dahlgren, A-C
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Centrum för kirurgi, ortopedi och cancervård, Radiofysikavdelningen US. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Which Orthodontic Brackets Are Most Suitable for MRI?2010Konferensbidrag (Refereegranskat)
  • 28.
    Klaastad, O.
    et al.
    Klaastad, Ø., Department of Anesthesiology, Interventional Centre, Rikshospitalet University Hospital, Oslo, Norway, Rikshospitalet University Hospital, Department of Anesthesiology, Sognsvannsveien 20, NO-0027 Oslo, Norway.
    Smedby, Örjan
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Kjelstrup, T.
    Department of Anesthesiology, Rikshospitalet University Hospital, Oslo, Norway.
    Smith, H.-J.
    Department of Radiology, Rikshospitalet University Hospital, Oslo, Norway.
    The vertical infraclavicular brachial plexus block: A simulation study using magnetic resonance imaging2005Ingår i: Anesthesia and Analgesia, ISSN 0003-2999, E-ISSN 1526-7598, Vol. 101, nr 1, s. 273-278Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recommended needle trajectory for the vertical infraclavicular brachial plexus block is anteroposterior, caudad to the middle of the clavicle. We studied the risk of pneumothorax and subclavian vessel puncture and the precision of this method by using magnetic resonance imaging in 20 adult volunteers. The trajectory aimed at the lung in six subjects, five of whom were women. However, pleural contact could be avoided in all subjects by halting needle advancement after contact with the subclavian vessels, plexus, or first rib. The subclavian vein was reached by the trajectory in three and the subclavian artery in five subjects. The trajectory had a median distance to the plexus (closest aspect) of 1 mm (range, 0-9 mm) and contacted the nerves in 9 subjects. In conclusion, there is a small probability that the needle may reach the pleura when a vertical infraclavicular brachial plexus block is performed, particularly in women, and a high probability that it will contact the subclavian vein or artery. Although the trajectory is close to the plexus, any medial deviation carries the risk of pleural or subclavian vessel contact at other depths. Clinical accuracy in defining the insertion point is critical. © 2005 by the International Anesthesia Research Society.

  • 29.
    Klaastad, O
    et al.
    University of Oslo .
    Smith, HJ
    University of Oslo .
    Smedby, Örjan
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Winther-Larssen, EH
    University of Oslo .
    Brodal, P
    University of Oslo .
    Breivik, H
    University of Oslo .
    Fosse, ET
    University of Oslo .
    Letter: A novel approach to infraclavicular brachial plexus block: The ultrasound experience - In response2004Ingår i: Anesthesia and Analgesia, ISSN 0003-2999, E-ISSN 1526-7598, Vol. 99, nr 3, s. 950-951Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    n/a

  • 30.
    Klaastad, Øivind
    et al.
    Department of Anesthesiology, Rikshospitalet University Hospital, Oslo, Norway.
    Smith, Hans-Jørgen
    Department of Radiology, Rikshospitalet University Hospital, Oslo, Norway.
    Smedby, Örjan
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Winther-Larssen, Eldrid H.
    Department of Radiology, Rikshospitalet University Hospital, Oslo, Norway.
    Brodal, Per
    Department of Anatomy, University of Oslo, Oslo, Norway.
    Breivik, Harald
    Department of Anesthesiology, Rikshospitalet University Hospital, Oslo, Norway.
    Fosse, Erik T.
    The Interventional Centre, Rikshospitalet University Hospital, Oslo, Norway.
    A novel infraclavicular brachial plexus block: The lateral and sagittal technique, developed by magnetic resonance imaging studies2004Ingår i: Anesthesia and Analgesia, ISSN 0003-2999, E-ISSN 1526-7598, Vol. 98, nr 1, s. 252-256Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new infraclavicular brachial plexus block method has the patient supine with an adducted arm. The target is any of the three cords behind the pectoralis minor muscle. The point of needle insertion is the intersection between the clavicle and the coracoid process. The needle is advanced 0degrees-30degrees posterior, always strictly in the sagittal plane next to the coracoid process while abutting the antero-inferior edge of the clavicle. We tested the new method using magnetic resonance imaging (MRI) in 20 adult volunteers, without inserting a needle. Combining 2 simulated needle directions by 15degrees posterior and 0degrees in the images of the volunteers, at least one cord in 19 of 20 volunteers was contacted. This occurred within a needle depth of 6.5 cm. In the sagittal plane of the method the shortest depth to the pleura among all volunteers was 7.5 cm. The MRI study indicates that the new infraclavicular technique may be efficient in reaching a cord of the brachial plexus, often not demanding more than two needle directions. The risk of pneumothorax should be minimal because the needle is inserted no deeper than 6.5 cm. However, this needs to be confirmed by a clinical study.

  • 31.
    Källman, Ulrika
    et al.
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för omvårdnad.
    Bergstrand, Sara
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet.
    Ek, Anna-Christina
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Akutkliniken.
    Engström, Maria
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Lindgren, Margareta
    Linköpings universitet, Institutionen för medicin och hälsa, Omvårdnad. Linköpings universitet, Hälsouniversitetet.
    Pressure ulcer prevention: The effect of different lying positions on tissue blood flow, temperature and interface pressure in elderly patients - an ongoing study2010Ingår i: Pressure ulcer prevention: The effect of different lying positions on tissue blood flow, temperature and interface pressure in elderly patients, 2010Konferensbidrag (Refereegranskat)
  • 32.
    Landtblom, Anne-Marie
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Neurologiska kliniken.
    Jaworski, Jacek
    Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Neurologiska kliniken.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Gustafsson, Maria C
    Östergötlands Läns Landsting, Närsjukvården i centrala Östergötland, Neurologiska kliniken.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Absolute metabolite concentrations in cerebral white matter of multiple sclerosis patients with beta interferon treatment2008Ingår i: MULTIPLE SCLEROSIS,ISSN 1352-4585: Volume 14, 2008, Vol. 14, s. S162-S162Konferensbidrag (Refereegranskat)
  • 33.
    Larsson, Martin
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Eriksson, Per
    Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Njurmedicinska kliniken.
    Kihlberg, Johan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Renal artery stenosis: extracting quantitative parameters with a mathematical model fitted to magnetic resonance blood flow data2008Ingår i: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 27, nr 1, s. 140-147Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To investigate the feasibility of quantitative parameter extraction from a mathematical model fitted to renal artery magnetic resonance flow data.

    Material and methods: Sixteen subjects, 8 patients and 8 normal controls, were examined with cine phase-contrast velocity measurements, and blood flow data from the aorta and both renal arteries were extracted by means of contour detection. A mathematical model with eight parameters describing the time, duration and amplitude of the systolic acceleration and the diastolic deceleration was fitted to the aorta and renal artery blood flow data from each subject. The curve fitting was evaluated with R2 values. Statistical analysis was performed with unpaired Wilcoxon tests and stepwise logistic regression.

    Results: Three data sets out of 48 yielded R2 values below 0.80 and were considered unreliable for parameter estimation. Basal flow was significantly, and systolic peak amplitude almost significantly, lower in stenotic arteries. Logistic regression indicated that two parameters describing basal flow and the duration of acceleration can accurately predict stenosis.

    Conclusion: The results suggest that it is technically feasible to fit a mathematical model to renal blood flow data, extracting quantitative parameters that may prove useful for quantification and diagnosis of renal artery stenosis.

  • 34.
    Leinhard, Olof Dahlqvist
    et al.
    Linköpings universitet, Institutionen för medicin och vård, Radiofysik. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet.
    Johansson, Andreas
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Rydell, Joakim
    Linköpings universitet, Institutionen för medicinsk teknik, Medicinsk informatik. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Nystöm, Fredrik
    Linköpings universitet, Institutionen för medicin och hälsa, Internmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Endokrin- och magtarmmedicinska kliniken US.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Borga, Magnus
    Linköpings universitet, Institutionen för medicinsk teknik, Medicinsk informatik. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Tekniska högskolan.
    Quantitative Abdominal Fat Estimation Using MRI2008Ingår i: Proceedings - International Conference on Pattern Recognition, IEEE Computer Society, 2008, s. 1-4Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper introduces a new method for automaticquantification of subcutaneous, visceral and nonvisceralinternal fat from MR-images acquired usingthe two point Dixon technique in the abdominal region.The method includes (1) a three dimensionalphase unwrapping to provide water and fat images, (2)an image intensity inhomogeneity correction, and (3) amorphon based registration and segmentation of thetissue. This is followed by an integration of the correctedfat images within the different fat compartmentsthat avoids the partial volume effects associated withtraditional fat segmentation methods. The method wastested on 18 subjects before and after a period of fastfoodhyper-alimentation showing high stability andperformance in all analysis steps.

  • 35.
    Lundström, Claes
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Visuell informationsteknologi och applikationer. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Ljung, Patric
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Visuell informationsteknologi och applikationer. Linköpings universitet, Tekniska högskolan.
    Ynnerman, Anders
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Visuell informationsteknologi och applikationer. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Persson, Anders
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Uncertainty Visualization in Medical Volume Rendering Using Probabilistic Animation2007Ingår i: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506, Vol. 13, nr 6, s. 1648-1655Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Direct volume rendering has proved to be an effective visualization method for medical data sets and has reached wide-spread clinical use. The diagnostic exploration, in essence, corresponds to a tissue classification task, which is often complex and time-consuming. Moreover, a major problem is the lack of information on the uncertainty of the classification, which can have dramatic consequences for the diagnosis. In this paper this problem is addressed by proposing animation methods to convey uncertainty in the rendering. The foundation is a probabilistic Transfer Function model which allows for direct user interaction with the classification. The rendering is animated by sampling the probability domain over time, which results in varying appearance for uncertain regions. A particularly promising application of this technique is a "sensitivity lens" applied to focus regions in the data set. The methods have been evaluated by radiologists in a study simulating the clinical task of stenosis assessment, in which the animation technique is shown to outperform traditional rendering in terms of assessment accuracy.

  • 36.
    Löfving, Adam
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet.
    Tizon, Xavier
    Université de Bourgogne.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Hälsouniversitetet.
    Angiographic visualization of the coronary arteries in computed tomography with virtual contrast injection2006Ingår i: The Internet Journal of Radiology, ISSN 1528-8404, Vol. 4, nr 2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Computed Tomography Angiography (CTA) is a non-invasive alternative to catheter angiography but has had limited use in the coronary arteries due to resolution and visualization problems. Maximum intensity projection (MIP) is difficult to apply in the heart with numerous overlying contrast-filled structures. The study proposes virtual contrast injection, originally introduced for MR angiography, for visualizing the coronaries in CTA. Examination after i.v. contrast injection was made in a 16-slice CT. After virtual contrast injection (concurrent grayscale connectedness) separating the vessels, rendering of the right and left coronary separately was made with MIP and volume rendering (VRT). Images similar to invasive angiography were obtained in all 7 projections used in the clinical routine. The observer also has the possibility to freely select an optimal projection. After validation in larger materials, this may become a clinically useful non-invasive alternative for examining coronary arteries.

  • 37.
    Magnusson, Maria
    et al.
    Linköpings universitet, Institutionen för systemteknik, Bildbehandling. Linköpings universitet, Tekniska högskolan.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Brynolfsson, Patrik
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Improved temporal resolution in radial k-space sampling using an hourglass filter2009Ingår i: ISMRM 17th Scientific Meeting & Exhibition, Honolulu, Hawaii, USA, 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Radial sampling of k-space is known to simultaneously provide both high spatial and high temporal resolution. Recently, an optimal radial profile time order based on the Golden Ratio was presented in [1]. We have adopted and modified the idea, with a focus onhigher temporal resolution without sacrificing any image quality.

    [1] Winkelmann et. al.: An optimal radial profile order based on the golden ratio for time-resolved MRI, IEEE Trans. Med. Im, Vol.26, No.1,2007.

  • 38.
    Magnusson, Maria
    et al.
    Linköpings universitet, Institutionen för systemteknik, Bildbehandling. Linköpings universitet, Tekniska högskolan.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Brynolfsson, Patrik
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Radial k-space sampling: step response using different filtering techniques2009Ingår i: ISMRM Workshop on Data sampling and Image Reconstruction, The Enchantment Resort, Sedona, Arizona, USA, 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Radial sampling of k-space is known to simultaneously provide both high spatial and high temporal resolution. Recently, an optimalradial profile time order based on the Golden Ratio was presented in [1]. We have adopted and modified the idea, with a focus onhigher temporal resolution without sacrificing any image quality.

    [1] Winkelmann et. al.: An optimal radial profileorder based on the golden ratio for time-resolved MRI, IEEE Trans. Med. Im, Vol.26, No.1, 2007.

  • 39.
    Magnusson, Maria
    et al.
    Linköpings universitet, Institutionen för systemteknik, Bildbehandling. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Brynolfsson, Patrik
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Thyr, Per
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Lundberg, Peter
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    3D Magnetic Resonance Imaging of the Human Brain - Novel Radial Sampling, Filtering and Reconstruction2010Ingår i: Proc of the 12th IASTED International Conference on Signal and Image Processing (SIP 2010), August 23 - 25, 2010, Lahaina, Maui, USA / [ed] B. Flinchbaugh, Calgary, AB, Canada: ACTA Press, 2010, s. Track: 710-042-(8 pages)Konferensbidrag (Refereegranskat)
    Abstract [en]

    We have suggested a novel method PRESTO-CAN including radial sampling, filtering and reconstruction of k-space data for 3D-plus-time resolved MRI. The angular increment of the profiles was based on the golden ratio, but the number of angular positions N was locked to be a prime number which guaranteed fix angle positions.The time resolution increased dramatically when the pro-files were partly removed from the k-space using the hourglass filter.We aim for utilizing the MRI-data for fMRI, where the echo times are long, TE ≈ 37-40 ms. This will result in field inhomogeneities and phase variations in the reconstructed images. Therefore, a new calibration and correction procedure was developed. We show that we are able to reconstruct images of the human brain with an image quality in line with what can be obtained by conventional Cartesian sampling.The pulse sequence for PRESTO-CAN was implemented by modifying an existing PRESTO sequence for Cartesian sampling. The effort involved was relatively small and a great advantage will be that we are able to use standard procedures for speeding up data acquisition, i.e. parallel imaging with SENSE.

  • 40.
    Matthiessen, P.
    et al.
    Department of Surgery, Örebro University Hospital, S-701 85 Örebro, Sweden.
    Henriksson, M.
    Department of Radiology, Örebro University Hospital, S-701 85 Örebro, Sweden.
    Hallböök, Olof
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Kirurgi. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Kirurgiska kliniken i Östergötland med verksamhet i Linköping, Norrköping och Motala.
    Grunditz, E.
    Department of Radiology, Vrinnevi Hospital, Norrköping, Sweden.
    Norén, Bengt
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Arbman, G.
    Department of Surgery, Vrinnevi Hospital, Norrköping, Sweden.
    Increase of serum C-reactive protein is an early indicator of subsequent symptomatic anastomotic leakage after anterior resection2008Ingår i: Colorectal Disease, ISSN 1462-8910, E-ISSN 1463-1318, Vol. 10, nr 1, s. 75-80Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: This prospective study investigated the factors which might indicate anastomotic leakage after low anterior resection.

    Method: Thirty-three patients who underwent anterior resection for rectal carcinoma (n = 32) and severe dysplasia (n = 1), were monitored daily by serum C-reactive protein (CRP) and white blood cell count (WBC) estimations until discharge from hospital. Computed tomography (CT) scans were performed on postoperative days 2 and 7 and the amount of presacral fluid collection was assessed. All patients had a pelvic drain and the volume of drainage was measured daily.

    Results: The level of the anastomosis was at a median 5 cm (3-12 cm) above the anal verge. There was no 30-day mortality. Nine (27.2%) of the 33 patients developed a symptomatic anastomotic leakage which was diagnosed at a median of 8 days (range 4-14) postoperatively. The serum CRP was increased in patients who leaked from postoperative day 2 onwards (P = 0.004 on day 2, P < 0.001 on day 3-8). The WBC was decreased in preoperatively irradiated patients on days 1-5 (P = 0.021), with no difference seen between patients with or without leakage. Patients with leakage had a larger presacral fluid collection on CT on day 7 (median 76 ml vs 52 ml, P = 0.016) and a larger increase in the fluid collection between the first and the second CT examinations (28 ml vs 3 ml, P = 0.046).

    Conclusion: An early rise in serum CRP was a strong indicator of leakage. Monitoring of CRP for possible early detection of symptomatic anastomotic leakage is recommended.

  • 41.
    Norén, Bengt
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Dahlqvist Leinhard, Olof
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Hälsouniversitetet.
    Lundberg, Peter
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiofysik. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Almer, Sven
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Gastroenterologi och hepatologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Endokrin- och magtarmmedicinska kliniken US.
    Kechagias, Stergios
    Linköpings universitet, Institutionen för medicin och hälsa, Internmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Endokrin- och magtarmmedicinska kliniken US.
    Ekstedt, Mattias
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Gastroenterologi och hepatologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Medicincentrum, Endokrin- och magtarmmedicinska kliniken US.
    Franzén, Lennart
    Medilab, Täby, Sweden.
    Wirell, Staffan
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Separation of advanced from mild fibrosis in diffuse liver disease using 31P magnetic resonance spectroscopy2008Ingår i: European Journal of Radiology, ISSN 0720-048X, E-ISSN 1872-7727, Vol. 66, nr 2, s. 313-320Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    31P-MRS using DRESS was used to compare absolute liver metabolite concentrations (PME, Pi, PDE, γATP, αATP, βATP) in two distinct groups of patients with chronic diffuse liver disorders, one group with steatosis (NAFLD) and none to moderate inflammation (n = 13), and one group with severe fibrosis or cirrhosis (n = 16). All patients underwent liver biopsy and extensive biochemical evaluation. A control group (n = 13) was also included. Absolute concentrations and the anabolic charge, AC = {PME}/({PME} + {PDE}), were calculated.

    Comparing the control and cirrhosis groups, lower concentrations of PDE (p = 0.025) and a higher AC (p < 0.001) were found in the cirrhosis group. Also compared to the NAFLD group, the cirrhosis group had lower concentrations of PDE (p = 0.01) and a higher AC (p = 0.009). No significant differences were found between the control and NAFLD group. When the MRS findings were related to the fibrosis stage obtained at biopsy, there were significant differences in PDE between stage F0–1 and stage F4 and in AC between stage F0–1 and stage F2–3.

    Using a PDE concentration of 10.5 mM as a cut-off value to discriminate between mild, F0–2, and advanced, F3–4, fibrosis the sensitivity and specificity were 81% and 69%, respectively. An AC cut-off value of 0.27 showed a sensitivity of 93% and a specificity of 54%.

    In conclusion, the results suggest that PDE is a marker of liver fibrosis, and that AC is a potentially clinically useful parameter in discriminating mild fibrosis from advanced.

  • 42.
    Persson, Anders
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Research ethics and the development of medical biotechnology2006Ingår i: Xenotransplantation, ISSN 0908-665X, E-ISSN 1399-3089, Vol. 13, s. 501-513Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Commercial funding is of most importance for the development of new biomedical technologies such as xenotransplantation. The dependence of such funding may, however, carry certain risks from an ethical point of view. In this article some of these risks are exemplified and it is argued that the adherence to basic research ethical norms are of vital importance for the field of xenotransplantation to develop properly.

  • 43.
    Persson, Anders
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Skiktröntgen undersöker hjärtat på några sekunder: The heart examined with tomography in few seconds2008Ingår i: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 105, nr 43, s. 3043-3046Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Selektiv kranskärlsröntgen är i dag den enda kliniska metod som kan avbilda och kvantifiera kranskärlsstenoser in vivo med tillräckligt hög säkerhet. Nackdelarna är att undersökningen är invasiv och relativt resurskrävande.

    Datortomografi är en teknik under konstant, snabb utveckling, och efter introduktionen av 64-kanalsdatortomografi har kranskärlsdatortomografi fått mycket snabb spridning i världen.

    Klinisk nytta har påvisats i ett flertal studier, dock saknas ännu stora randomiserade, prospektiva studier.

    Metoden medger anatomisk kartläggning av kranskärlslumen och kärlvägg med begränsad möjlighet till bedömning av blodflöde. Högt negativt prediktivt värde för kranskärlssjukdom och risk för överskattning av kärlstenoser har påvisats. Kalk i kärlvägg och oregelbunden hjärtfrekvens försvårar bedömningen kraftigt.

    Stråldosbelastningen är apparatgenerationsberoende och varierar kraftigt från låg till hög dos.

    Metoden utvecklas snabbt och har stor potential för framtiden, men i dagsläget är den inte lämpad för daglig sjukvård och bör begränsas till att användas inom ramen för kontrollerade studier.

  • 44.
    Persson, Anders
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Brismar, Torkel
    Karolinska Institutet, CLINTEC, Röntgenavdelningen, Karolinska Universitetssjukhuset Huddinge.
    Lundström, Claes
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Visuell informationsteknologi och applikationer. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Dahlström, Nils
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Othberg, Fredrik
    Linköpings universitet, Institutionen för medicinsk teknik, Centrum för medicinsk bildvetenskap och visualisering. Linköpings universitet, Hälsouniversitetet.
    Standardized volume rendering for magnetic resonance angiography measurements in the abdominal aorta2006Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 47, nr 2, s. 172-178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To compare three methods for standardizing volume rendering technique (VRT) protocols by studying aortic diameter measurements in magnetic resonance angiography (MRA) datasets.

    Material and Methods: Datasets from 20 patients previously examined with gadolinium-enhanced MRA and with digital subtraction angiography (DSA) for abdominal aortic aneurysm were retrospectively evaluated by three independent readers. The MRA datasets were viewed using VRT with three different standardized transfer functions: the percentile method (Pc-VRT), the maximum-likelihood method (ML-VRT), and the partial range histogram method (PRH-VRT). The aortic diameters obtained with these three methods were compared with freely chosen VRT parameters (F-VRT) and with maximum intensity projection (MIP) concerning inter-reader variability and agreement with the reference method DSA.

    Results: F-VRT parameters and PRH-VRT gave significantly higher diameter values than DSA, whereas Pc-VRT gave significantly lower values than DSA. The highest interobserver variability was found for F-VRT parameters and MIP, and the lowest for Pc-VRT and PRH-VRT. All standardized VRT methods were significantly superior to both MIP and F-VRT in this respect. The agreement with DSA was best for PRH-VRT, which was the only method with a mean error below 1 mm and which also had the narrowest limits of agreement (95% of cases between 2.1 mm below and 3.1 mm above DSA).

    Conclusion: All the standardized VRT methods compare favorably with MIP and VRT with freely selected parameters as regards interobserver variability. The partial range histogram method, although systematically overestimating vessel diameters, gives results closest to those of DSA.

  • 45.
    Persson, Anders
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet.
    Dahlström, Nils
    Department of Radiology, Hudiksvall Hospital, Sweden.
    Engellau, Lena
    Department of Radiology, Lund University, Malmö University Hospital.
    Larsson, Elna-Marie
    Department of Radiology, Lund University Hospital.
    Brismar, Torkel B.
    Center for Surgical Sciences, Division of Radiology, Karolinska Institutet, Stockholm.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Volume rendering compared with maximum intensity projection for magnetic resonance angiography measurements of the abdominal aorta2004Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 45, nr 4, s. 453-459Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To compare the volume rendering technique (VRT) with maximum intensity projection (MIP) for aortic diameter measurements in MR angiography (MRA) data sets.

    Material and Methods: Existing contrast-enhanced 3-dimensional MRA and digital subtraction angiography (DSA) data sets from 20 patients were analyzed. In each MRA data set, two aortic diameters were measured using MIP and VRT. Agreement with DSA measurements, dependence on rendering parameters, and interobserver agreement were assessed.

    Results: Diameters measured on MIP with fixed parameters showed no significant difference compared with DSA and with freely selected parameters a slight overestimation relative to DSA. Diameters measured on VRT were larger than on DSA. For both MIP and VRT, the measurements depended on the chosen parameters. The error relative to DSA was larger for VRT than for MIP with fixed parameters but not with freely chosen parameters. Interobserver agreement did not differ significantly.

    Conclusions: VRT is not suitable for diameter measurements of the abdominal aorta with fixed parameter settings but may be useful with user-selected settings.

  • 46.
    Persson, Anders
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi.
    Dahlström, Nils
    Department of Radiology, Hudiksvall Hospital, Sweden .
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Brismar, T. B.
    Division of Radiology, Karolinska Institutet, Sweden .
    Three-dimensional drip infusion CT cholangiography in patients with suspected obstructive biliary disease: a retrospective analysis of feasibility and adverse reaction to contrast material2006Ingår i: BMC Medical Imaging, ISSN 1471-2342, E-ISSN 1471-2342, Vol. 6, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    Computed Tomography Cholangiography (CTC) is a fast and widely available alternative technique to visualise hepatobiliary disease in patients with an inconclusive ultrasound when MRI cannot be performed. The method has previously been relatively unknown and sparsely used, due to concerns about adverse reactions and about image quality in patients with impaired hepatic function and thus reduced contrast excretion. In this retrospective study, the feasibility and the frequency of adverse reactions of CTC when using a drip infusion scheme based on bilirubin levels were evaluated.

    Methods

    The medical records of patients who had undergone upper abdominal spiral CT with subsequent three-dimensional rendering of the biliary tract by means of CTC during seven years were retrospectively reviewed regarding serum bilirubin concentration, adverse reaction and presence of visible contrast media in the bile ducts at CT examination. In total, 153 consecutive examinations in 142 patients were reviewed.

    Results

    Contrast media was observed in the bile ducts at 144 examinations. In 110 examinations, the infusion time had been recorded in the medical records. Among these, 42 examinations had an elevated bilirubin value (>19 umol/L). There were nine patients without contrast excretion; 3 of which had a normal bilirubin value and 6 had an elevated value (25–133 umol/L). Two of the 153 examinations were inconclusive. One subject (0.7%) experienced a minor adverse reaction – a pricking sensation in the face. No other adverse effects were noted.

    Conclusion

    We conclude that drip infusion CTC with an infusion rate of the biliary contrast agent iotroxate governed by the serum bilirubin value is a feasible and safe alternative to MRC in patients with and without impaired biliary excretion.

    In this retrospective study the feasibility and the frequency of adverse reactions when using a drip infusion scheme based on bilirubin levels has been evaluated.

  • 47.
    Persson, Anders
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiologi. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Dahlström, Nils
    Department of Radiology, Hudiksvall Hospital, Sweden.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för medicin och vård, Medicinsk radiofysik. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Brismar, T.B.
    Department of Radiology, Karolinska University Hospital, Huddinge, Stockholm, Sweden .
    Volume rendering of three-dimensional drip infusion CT cholangiography in patients with suspected obstructive biliary disease: a retrospective study2005Ingår i: British Journal of Radiology, ISSN 0007-1285, E-ISSN 1748-880X, Vol. 78, nr 936, s. 1078-1085Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this study was to evaluate the diagnostic potential of prolonged drip infusion CT cholangiography (DIC-CT) using meglumine iotroxate (Biliscopin®) and 3D volume rendering in patients with suspected obstructive biliary disease. From a material of 142 patients who had undergone a drip infusion CT, all cases with a verified surgical or endoscopic retrograde cholangiography (ERC) diagnosis (n=33) were selected. Age-matched controls were selected from the remaining examinations. Three radiologists reviewed all 66 examinations in retrospect, independently as well as in consensus. The image quality and the estimated diagnostic quality were rated as good or moderate in 91% of the 198 reviews. The consensus sensitivity and specificity for diagnosing biliary stones was 88% and 94%, respectively (with sensitivities ranging from 88% to 94% for individual observers, and specificities from 86% to 96%). Two out of three strictures were observed. No false positive strictures were described. The use of volume rendering technique (VRT) improved diagnostic certainty in 28/198 (14%) of the evaluations. The visualization of ductal stones was improved in 18/48 (38%). No differences in diagnostic quality between single and multislice CT were observed. We conclude that a detailed image of the biliary tree with good sensitivity and specificity can be obtained by means of bilirubin-governed infusion time DIC-CT with volume rendering reconstruction.

  • 48.
    Petersson, Helge
    et al.
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Hälsouniversitetet.
    Sinkvist, David
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Wang, Chunliang
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Smedby, Örjan
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Web-based interactive 3D visualization as a tool for improved anatomy learning2009Ingår i: Anatomical sciences education, ISSN 1935-9772, Vol. 2, nr 2, s. 61-68Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite a long tradition, conventional anatomy education based on dissection is declining. This study tested a new virtual reality (VR) technique for anatomy learning based on virtual contrast injection. The aim was to assess whether students value this new three-dimensional (3D) visualization method as a learning tool and what value they gain from its use in reaching their anatomical learning objectives. Several 3D vascular VR models were created using an interactive segmentation tool based on the "virtual contrast injection" method. This method allows users, with relative ease, to convert computer tomography or magnetic resonance images into vivid 3D VR movies using the OsiriX software equipped with the CMIV CTA plug-in. Once created using the segmentation tool, the image series were exported in Quick Time Virtual Reality (QTVR) format and integrated within a web framework of the Educational Virtual Anatomy (EVA) program. A total of nine QTVR movies were produced encompassing most of the major arteries of the body. These movies were supplemented with associated information, color keys, and notes. The results indicate that, in general, students' attitudes towards the EVA-program were positive when compared with anatomy textbooks, but results were not the same with dissections. Additionally, knowledge tests suggest a potentially beneficial effect on learning.

  • 49.
    Petoral, Rodrigo M
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Söderlind, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Klasson, Anna
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Suska, Anke
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tillämpad Fysik. Linköpings universitet, Tekniska fakulteten.
    Fortin, Marc-André
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Abrikossova, Natalia
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Selegard, Linnea
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensorvetenskap och Molekylfysik. Linköpings universitet, Tekniska högskolan.
    Käll, Per-Olov
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Fysikalisk Kemi. Linköpings universitet, Tekniska högskolan.
    Engström, Maria
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping.
    Uvdal, Kajsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Molekylär ytfysik och nanovetenskap. Linköpings universitet, Tekniska fakulteten.
    Synthesis and Characterization of Tb3+-Doped Gd2O3 Nanocrystals: A Bifunctional Material with Combined Fluorescent Labeling and MRI Contrast Agent Properties2009Ingår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 113, nr 17, s. 6913-6920Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ultrasmall gadolinium oxide nanoparticles doped with terbium ions were synthesized by the polyol route and characterized as a potentially bifunctional material with both fluorescent and magnetic contrast agent properties. The structural, optical, and magnetic properties of the organic-acid-capped and PEGylated Gd2O3:Tb3+ nanocrystals were studied by HR-TEM, XPS, EDX, IR, PL, and SQUID. The luminescent/fluorescent property of the particles is attributable to the Tb3+ ion located on the crystal lattice of the Gd2O3 host. The paramagnetic behavior of the particles is discussed. Pilot studies investigating the capability of the nanoparticles for fluorescent labeling of living cells and as a MRI contrast agent were also performed. Cells of two cell lines (THP-1 cells and fibroblasts) were incubated with the particles, and intracellular particle distribution was visualized by confocal microscopy. The MRI relaxivity of the PEGylated nanoparticles in water at low Gd concentration was assessed showing a higher T-1 relaxation rate compared to conventional Gd-DTPA chelates and comparable to that of undoped Gd2O3 nanoparticles.

  • 50.
    Ragnehed, Mattias
    Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Bildmedicinskt centrum, Röntgenkliniken i Linköping. Östergötlands Läns Landsting, Kirurgi- och onkologicentrum, Radiofysikavdelningen.
    Functional Magnetic Resonance Imaging for Clinical Diagnosis: Exploring and Improving the Examination Chain2009Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Functional Magnetic Resonance Imaging (fMRI) is a relatively new imaging technique, first reported in 1992, which enables mapping of brain functions with high spatial resolution. Functionally active areas are distinguished by a small signal increase mediated by changes in local blood oxygenation in response to neural activity. The ability to non-invasively map brain function and the large number of MRI scanners quickly made the method very popular, and fMRI have had a huge impact on the study of brain function, both in healthy and diseased subjects.

    The most common clinical application of fMRI is pre-surgical mapping of brain functions in order to optimise surgical interventions. The clinical fMRI examination procedure can be divided into four integrated parts: (1) patient preparation, (2) image acquisition, (3) image analysis and (4) clinical decision. In this thesis, important aspects of all parts of the fMRI examination procedure are explored with the aim to provide recommendations and methods for prosperous clinical usage of the technique.

    The most important results of the thesis were: (I) administration of low doses of diazepam to reduce anxiety did not invalidate fMRI mapping results of primary motor and language areas, (II) the choice of visual stimuli equipment can have severe impact on the mapping of visual areas, (III) three-dimensional fMRI imaging sequences did not perform better than two-dimensional imaging sequences, (IV) adaptive spatial filtering can improve the fMRI data analysis, (V) clinical decisions should not be based on activation results from a single statistical threshold.

    Delarbeten
    1. Influence of diazepam on clinically designed FMRI
    Öppna denna publikation i ny flik eller fönster >>Influence of diazepam on clinically designed FMRI
    Visa övriga...
    2007 (Engelska)Ingår i: The Journal of Neuropsychiatry and Clinical Neurosciences, ISSN 0895-0172, E-ISSN 1545-7222, Vol. 19, nr 2, s. 164-172Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The authors investigated the effect of diazepam on clinically relevant measures from functional magnetic resonance imaging (fMRI) examinations. Twenty volunteers were scanned twice. Using a double-blind randomized study design, the volunteers received placebo on one occasion, and on the other, 5 mg of diazepam. Three functional tests were used: motor, word generation, and working memory. Images were analyzed individually for each subject and the number of activated voxels and the laterality index were calculated. No significant effects related to the drug were detected. In contrast, the motor and working memory tasks showed a significant decrease in the number of activated voxels between Sessions 1 and 2, independently of diazepam administration. These results indicate that diazepam may be administered for premedication prior to fMRI investigations.

    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-17989 (URN)10.1176/appi.neuropsych.19.2.164 (DOI)000245666300009 ()17431063 (PubMedID)
    Tillgänglig från: 2009-04-30 Skapad: 2009-04-30 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    2. Projection screen or video goggles as stimulus modality in functional magnetic resonance imaging
    Öppna denna publikation i ny flik eller fönster >>Projection screen or video goggles as stimulus modality in functional magnetic resonance imaging
    2005 (Engelska)Ingår i: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 23, nr 5, s. 695-699Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The purpose of this study was to investigate the reliability of functional magnetic resonance imaging (fMRI) by using either a projection screen or video goggles as stimulus modality. A sequence of visual stimuli were presented to the same subject at different occasions. The sequence was optimized with a genetic algorithm. In five sessions the stimuli were presented using a projection screen viewed through a mirror in the head coil and in five sessions using video goggles. Failure to detect visual activation in the medial left hemisphere was observed in sessions using the projection screen as stimulus modality. Decreased thresholds for P values and cluster size resulted in activation outside the occipital lobe and did not significantly increase activated areas in this region. Results in this study indicate that presentation of fMRI tasks with visual routes is more reliable with direct input through video goggles than with the conventional use of projection screens. Failure to detect crucial visual areas has severe consequences for tumor surgery in the visual cortex. Inferior visual impression might also have negative consequences for cognitive tests with high demand on attention and perception.

    Nyckelord
    fMRI; Visual; Projection screen; Video goggles; Reliability
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-17992 (URN)10.1016/j.mri.2005.04.006 (DOI)16051046 (PubMedID)
    Tillgänglig från: 2009-04-30 Skapad: 2009-04-30 Senast uppdaterad: 2017-12-13Bibliografiskt granskad
    3. Visual Grading of 2D and 3D fMRI compared to image based descriptive measures
    Öppna denna publikation i ny flik eller fönster >>Visual Grading of 2D and 3D fMRI compared to image based descriptive measures
    Visa övriga...
    2010 (Engelska)Ingår i: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 20, nr 3, s. 714-724Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    A prerequisite for successful clinical use of functional Magnetic Resonance Imaging (fMRI) is the selection of an appropriate imaging sequence. In this paper, 2D and 3D fMRI sequences were compared using different image quality assessment methods. Descriptive image measures, such as activation volume and temporal signal-to-noise ratio (TSNR), were compared with results from Visual Grading Characteristics (VGC) analysis of the fMRI results. It was found that significant differences in activation volume and TSNR were not directly reflected by differences in VGC scores. The results suggest that better performance on descriptive image measures is not always an indicator of improved diagnostic quality of the fMRI results. In conclusion, in addition to descriptive image measures, it is important to include measures of diagnostic quality when comparing different fMRI data acquisition methods.

    Ort, förlag, år, upplaga, sidor
    Berlin / Heidelberg: Springer, 2010
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-17994 (URN)10.1007/s00330-009-1578-0 (DOI)000274544800023 ()19727748 (PubMedID)
    Anmärkning

    The original publication is available at www.springerlink.com: Mattias Ragnehed, Olof Dahlqvist Leinhard, Johan Pihlsgård, Staffan Wirell, Hannibal Sökjer, Patrik Fägerstam, Bo Jiang, Örjan Smedby, Maria Engström and Peter Lundberg, Visual Grading of 2D and 3D fMRI compared to image based descriptive measures, 2010, European Radiology, (20), 3, 714-724. http://dx.doi.org/10.1007/s00330-009-1578-0 Copyright: Springer Science Business Media http://www.springerlink.com/

    Tillgänglig från: 2009-04-30 Skapad: 2009-04-30 Senast uppdaterad: 2019-06-14Bibliografiskt granskad
    4. Restricted Canonical Correlation Analysis in Functional MRI-Validation and a Novel Thresholding Technique
    Öppna denna publikation i ny flik eller fönster >>Restricted Canonical Correlation Analysis in Functional MRI-Validation and a Novel Thresholding Technique
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    2009 (Engelska)Ingår i: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 29, nr 1, s. 146-154Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Purpose: To validate the performance of an analysis method for fMRI data based on restricted canonical correlation analysis (rCCA) and adaptive filtering, and to increase the usability of the method by introducing a new technique for significance estimation of rCCA maps.

    Materials and Methods: Activation data from a language task and also a resting state fMRI data were collected from eight volunteers. Data was analyzed using both the rCCA method and the General Linear Model (GLM). A modified Receiver Operating Characteristic (ROC) method was used to evaluate the performance of the different analysis methods. The area under a fraction of the ROC curve was used as a measure of performance. On resting state data the fraction of voxels above certain significance thresholds were used to evaluate the significance estimation method.

    Results: The rCCA method scored significantly higher on the area under the ROC curve than the GLM. The fraction of activated voxels determined by thresholding according to the introduced significance estimation technique showed good agreement with the thresholds selected.

    Conclusion: The rCCA method is an effective analysis tool for fMRI data and its usability is increased with the introduced significance estimation method.

    Nyckelord
    fMRI, GLM, canonical correlation analysis, thresholding, significance
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-16411 (URN)10.1002/jmri.21494 (DOI)000262168200019 ()
    Tillgänglig från: 2009-01-23 Skapad: 2009-01-23 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    5. Right-hemispheric brain activation correlates to language performance
    Öppna denna publikation i ny flik eller fönster >>Right-hemispheric brain activation correlates to language performance
    Visa övriga...
    2010 (Engelska)Ingår i: NEUROIMAGE, ISSN 1053-8119, Vol. 49, nr 4, s. 3481-3488Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Language function in the right-hemispheric homologues of Brocas and Wernickes areas does not only correlate with left-handedness or pathology, but occurs naturally in right-handed healthy subjects as well. In the current study, two non-invasive methods of assessing language lateralization are correlated with behavioral results in order to link hemispheric dominance to language ability in healthy subjects. Functional magnetic resonance imaging (fMRI) together with a sentence-completion paradigm was used to determine region-specific lateralization indices in the left- and right-sided Brocas and Wernickes areas, the frontal temporal lobe, the anterior cingulate cortex and the parietal lobe. In addition, dichotic listening results were used to determine overall language lateralization and to strengthen conclusions by correlating with fMRI indices. Results showed that fMRI lateralization in the superior parietal, the posterior temporal, and the anterior cingulate cortices correlated to dichotic listening. A decreased right ear advantage (REA), which indicates less left- hemispheric dominance in language, correlated with higher performance in most administered language tasks, including reading, language ability, fluency, and non-word discrimination. Furthermore, right hemispheric involvement in the posterior temporal lobe and the homologue of Brocas area suggests better performance in behavioral language tasks. This strongly indicates a supportive role of the right-hemispheric counterparts of Brocas and Wernickes areas in language performance.

    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-53932 (URN)10.1016/j.neuroimage.2009.10.041 (DOI)000274064500059 ()
    Anmärkning
    Original Publication: Helene M van Ettinger-Veenstra, Mattias Ragnehed, Mathias Hällgren, Thomas Karlsson, Anne-Marie Landtblom, Peter Lundberg and Maria Engström, Right-hemispheric brain activation correlates to language performance, 2010, NEUROIMAGE, (49), 4, 3481-3488. http://dx.doi.org/10.1016/j.neuroimage.2009.10.041 Copyright: Elsevier Science B.V., Amsterdam http://www.elsevier.com/Tillgänglig från: 2010-02-12 Skapad: 2010-02-12 Senast uppdaterad: 2014-10-02
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