liu.seSearch for publications in DiVA
Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 238) Show all publications
Witt, S. T., Drissi, N. M., Tapper, S., Wretman, A., Szakács, A., Hallböök, T., . . . Engström, M. (2018). Evidence for cognitive resource imbalance in adolescents with narcolepsy. Brain Imaging and Behavior, 12(2), 411-424
Open this publication in new window or tab >>Evidence for cognitive resource imbalance in adolescents with narcolepsy
Show others...
2018 (English)In: Brain Imaging and Behavior, ISSN 1931-7557, E-ISSN 1931-7565, Vol. 12, no 2, p. 411-424Article in journal (Refereed) Published
Abstract [en]

The study investigated brain activity changes during performance of a verbal working memory task in a population of adolescents with narcolepsy. Seventeen narcolepsy patients and twenty healthy controls performed a verbal working memory task during simultaneous fMRI and EEG acquisition. All subjects also underwent MRS to measure GABA and Glutamate concentrations in the medial prefrontal cortex. Activation levels in the default mode network and left middle frontal gyrus were examined to investigate whether narcolepsy is characterized by an imbalance in cognitive resources. Significantly increased deactivation within the default mode network during task performance was observed for the narcolepsy patients for both the encoding and recognition phases of the task. No evidence for task performance deficits or reduced activation within the left middle frontal gyrus was noted for the narcolepsy patients. Correlation analyses between the spectroscopy and fMRI data indicated that deactivation of the anterior aspect of the default mode in narcolepsy patients correlated more with increased concentrations of Glutamate and decreased concentrations of GABA. In contrast, deactivation in the default mode was correlated with increased concentrations of GABA and decreased concentrations of Glutamate in controls. The results suggested that narcolepsy is not characterized by a deficit in working memory but rather an imbalance of cognitive resources in favor of monitoring and maintaining attention over actual task performance. This points towards dysregulation within the sustained attention system being the origin behind self-reported cognitive difficulties in narcolepsy.

Place, publisher, year, edition, pages
Springer-Verlag New York, 2018
Keywords
EEG, GABA, MRS, Narcolepsy, Working memory, fMRI
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-145535 (URN)10.1007/s11682-017-9706-y (DOI)000429029000011 ()28321606 (PubMedID)2-s2.0-85015625386 (Scopus ID)
Available from: 2018-03-05 Created: 2018-03-05 Last updated: 2018-05-17Bibliographically approved
Tapper, S., Tisell, A. & Lundberg, P. (2017). How does motion affect GABA-measurements? Order statistic filtering compared to conventional analysis of MEGA-PRESS MRS. PLoS ONE, 12(5), Article ID e0177795.
Open this publication in new window or tab >>How does motion affect GABA-measurements? Order statistic filtering compared to conventional analysis of MEGA-PRESS MRS
2017 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 5, article id e0177795Article in journal (Refereed) Published
Abstract [en]

Purpose The aim of this study was to evaluate two post-processing techniques applied to MRS MEGA-PRESS data influenced by motion-induced artifacts. In contrast to the conventional averaging technique, order statistic filtering (OSF) is a known method for artifact reduction. Therefore, this method may be suitable to incorporate in the GABA quantification. Methods Twelve healthy volunteers were scanned three times using a 3 T MR system. One measurement protocol consisted of two MEGA-PRESS measurements, one reference measurement and one measurement including head motions. The resulting datasets were analyzed with the standard averaging technique and with the OSF-technique in two schemes; filtering phase cycles RAW PC and filtering dynamics RAW Dyn. Results The datasets containing artifacts resulted in an underestimation of the concentrations. There was a trend for the OSF-technique to compensate for this reduction when quantifying SNR-intense signals. However, there was no indication that OSF improved the estimated GABA concentrations. Moreover, when only considering the reference measurements, the OSF technique was equally as effective as averaging, which suggests that the techniques are interchangeable. Conclusion OSF performed equally well as the conventional averaging technique for low-SNR signals. For high-SNR signals, OSF performed better and thus could be considered for routine usage.

Place, publisher, year, edition, pages
Public Library of Science, 2017
National Category
Signal Processing
Identifiers
urn:nbn:se:liu:diva-138250 (URN)10.1371/journal.pone.0177795 (DOI)000401485500071 ()28520793 (PubMedID)2-s2.0-85019539851 (Scopus ID)
Note

Funding Agencies|Knut and Alice Wallenberg Foundation [KAW 2013.0076]; NIH [P41 015909, R01 016089]

Available from: 2017-06-14 Created: 2017-06-14 Last updated: 2018-04-17Bibliographically approved
Håkansson, I., Tisell, A., Cassel, P., Blennow, K., Zetterberg, H., Lundberg, P., . . . Ernerudh, J. (2017). Neurofilament light chain in cerebrospinal fluid and prediction of disease activity in clinically isolated syndrome and relapsing-remitting multiple sclerosis. European Journal of Neurology, 24(5), 703-712
Open this publication in new window or tab >>Neurofilament light chain in cerebrospinal fluid and prediction of disease activity in clinically isolated syndrome and relapsing-remitting multiple sclerosis
Show others...
2017 (English)In: European Journal of Neurology, ISSN 1351-5101, E-ISSN 1468-1331, Vol. 24, no 5, p. 703-712Article in journal (Refereed) Published
Abstract [en]

Background and purpose: Improved biomarkers are needed to facilitate clinical decision-making and as surrogate endpoints in clinical trials in multiple sclerosis (MS). We assessed whether neurodegenerative and neuroinflammatory markers in cerebrospinal fluid (CSF) at initial sampling could predict disease activity during 2 years of follow-up in patients with clinically isolated syndrome (CIS) and relapsing-remitting MS. Methods: Using multiplex bead array and enzyme-linked immunosorbent assay, CXCL1, CXCL8, CXCL10, CXCL13, CCL20, CCL22, neurofilament light chain (NFL), neurofilament heavy chain, glial fibrillary acidic protein, chitinase-3-like-1, matrix metalloproteinase-9 and osteopontin were analysed in CSF from 41 patients with CIS or relapsing-remitting MS and 22 healthy controls. Disease activity (relapses, magnetic resonance imaging activity or disability worsening) in patients was recorded during 2 years of follow-up in this prospective longitudinal cohort study. Results: In a logistic regression analysis model, NFL in CSF at baseline emerged as the best predictive marker, correctly classifying 93% of patients who showed evidence of disease activity during 2 years of follow-up and 67% of patients who did not, with an overall proportion of 85% (33 of 39 patients) correctly classified. Combining NFL with either neurofilament heavy chain or osteopontin resulted in 87% overall correctly classified patients, whereas combining NFL with a chemokine did not improve results. Conclusions: This study demonstrates the potential prognostic value of NFL in baseline CSF in CIS and relapsing-remitting MS and supports its use as a predictive biomarker of disease activity.

Place, publisher, year, edition, pages
WILEY, 2017
Keywords
biomarker; clinically isolated syndrome; disease activity; multiple sclerosis; neurofilament light chain
National Category
Neurology
Identifiers
urn:nbn:se:liu:diva-137379 (URN)10.1111/ene.13274 (DOI)000399704400010 ()28261960 (PubMedID)
Note

Funding Agencies|Swedish Research Council [K2013-61X-22310-01-4]; Linkoping University, Sweden; University Hospital Linkoping, Sweden; Novartis; Torsten Soderberg foundation; Royal Academy of Sciences, Sweden

Available from: 2017-05-18 Created: 2017-05-18 Last updated: 2018-04-17
Blystad, I., Warntjes, M. J., Smedby, Ö., Lundberg, P., Larsson, E.-M. & Tisell, A. (2017). Quantitative MRI for analysis of peritumoral edema in malignant gliomas. PLoS ONE, 12(5), Article ID e0177135.
Open this publication in new window or tab >>Quantitative MRI for analysis of peritumoral edema in malignant gliomas
Show others...
2017 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 5, article id e0177135Article in journal (Refereed) Published
Abstract [en]

Background and purpose Damage to the blood-brain barrier with subsequent contrast enhancement is a hallmark of glioblastoma. Non-enhancing tumor invasion into the peritumoral edema is, however, not usually visible on conventional magnetic resonance imaging. New quantitative techniques using relaxometry offer additional information about tissue properties. The aim of this study was to evaluate longitudinal relaxation R-1, transverse relaxation R-2, and proton density in the peritumoral edema in a group of patients with malignant glioma before surgery to assess whether relaxometry can detect changes not visible on conventional images. Methods In a prospective study, 24 patients with suspected malignant glioma were examined before surgery. A standard MRI protocol was used with the addition of a quantitative MR method (MAGIC), which measured R-1, R-2, and proton density. The diagnosis of malignant glioma was confirmed after biopsy/surgery. In 19 patients synthetic MR images were then created from the MAGIC scan, and ROIs were placed in the peritumoral edema to obtain the quantitative values. Dynamic susceptibility contrast perfusion was used to obtain cerebral blood volume (rCBV) data of the peritumoral edema. Voxel-based statistical analysis was performed using a mixed linear model. Results R-1, R-2, and rCBV decrease with increasing distance from the contrast-enhancing part of the tumor. There is a significant increase in R1 gradient after contrast agent injection (Pamp;lt;.0001). There is a heterogeneous pattern of relaxation values in the peritumoral edema adjacent to the contrast-enhancing part of the tumor. Conclusion Quantitative analysis with relaxometry of peritumoral edema in malignant gliomas detects tissue changes not visualized on conventional MR images. The finding of decreasing R-1 and R-2 means shorter relaxation times closer to the tumor, which could reflect tumor invasion into the peritumoral edema. However, these findings need to be validated in the future.

Place, publisher, year, edition, pages
PUBLIC LIBRARY SCIENCE, 2017
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-138480 (URN)10.1371/journal.pone.0177135 (DOI)000402058800007 ()28542553 (PubMedID)
Note

Funding Agencies|Medical Research Council of Southeast Sweden [FORSS-234551]

Available from: 2017-06-19 Created: 2017-06-19 Last updated: 2018-04-17
Nasr, P., Forsgren, M. F., Ignatova, S., Dahlström, N., Cedersund, G., Dahlqvist Leinhard, O., . . . Kechagias, S. (2017). Using a 3% Proton Density Fat Fraction as a Cut-off Value Increases Sensitivity of Detection of Hepatic Steatosis, Based on Results from Histopathology Analysis. Gastroenterology, 153(1), 53-+
Open this publication in new window or tab >>Using a 3% Proton Density Fat Fraction as a Cut-off Value Increases Sensitivity of Detection of Hepatic Steatosis, Based on Results from Histopathology Analysis
Show others...
2017 (English)In: Gastroenterology, ISSN 0016-5085, E-ISSN 1528-0012, Vol. 153, no 1, p. 53-+Article in journal (Refereed) Published
Abstract [en]

It is possible to estimate hepatic triglyceride content by calculating the proton density fat fraction (PDFF), using proton magnetic resonance spectroscopy (less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS), instead of collecting and analyzing liver biopsies to detect steatosis. However, the current PDFF cut-off value (5%) used to define steatosis by magnetic resonance was derived from studies that did not use histopathology as the reference standard. We performed a prospective study to determine the accuracy of less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF in measurement of steatosis using histopathology analysis as the standard. We collected clinical, serologic, less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF, and liver biopsy data from 94 adult patients with increased levels of liver enzymes (6 months or more) referred to the Department of Gastroenterology and Hepatology at Linköping University Hospital in Sweden from 2007 through 2014. Steatosis was graded using the conventional histopathology method and fat content was quantified in biopsy samples using stereological point counts (SPCs). We correlated less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF findings with SPCs (r = 0.92; P less than.001). less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF results correlated with histopathology results (ρ = 0.87; P less than.001), and SPCs correlated with histopathology results (ρ = 0.88; P less than.001). All 25 subjects with PDFF values of 5.0% or more had steatosis based on histopathology findings (100% specificity for PDFF). However, of 69 subjects with PDFF values below 5.0% (negative result), 22 were determined to have steatosis based on histopathology findings (53% sensitivity for PDFF). Reducing the PDFF cut-off value to 3.0% identified patients with steatosis with 100% specificity and 79% sensitivity; a PDFF cut-off value of 2.0% identified patients with steatosis with 94% specificity and 87% sensitivity. These findings might be used to improve non-invasive detection of steatosis.

Place, publisher, year, edition, pages
Elsevier, 2017
National Category
Gastroenterology and Hepatology
Identifiers
urn:nbn:se:liu:diva-136544 (URN)10.1053/j.gastro.2017.03.005 (DOI)000403918300022 ()
Note

Funding agencies: Swedish Research Council/Medicine and Health [VR/M 2007-2884, VR/M 2012-3199]; Swedish Research Council/Natural and Engineering Sciences [VR/NT 2014-6157]; Swedish Innovation Agency VINNOVA [2013-01314]; Region Ostergotland (ALF)

Available from: 2017-04-19 Created: 2017-04-19 Last updated: 2018-04-18Bibliographically approved
Van Ettinger-Veenstra, H., Mcallister, A., Lundberg, P., Karlsson, T. & Engström, M. (2016). Higher Language Ability is Related to Angular Gyrus Activation Increase During Semantic Processing, Independent of Sentence Incongruency. Frontiers in Human Neuroscience, 10(110)
Open this publication in new window or tab >>Higher Language Ability is Related to Angular Gyrus Activation Increase During Semantic Processing, Independent of Sentence Incongruency
Show others...
2016 (English)In: Frontiers in Human Neuroscience, ISSN 1662-5161, E-ISSN 1662-5161, Vol. 10, no 110Article in journal (Refereed) Published
Abstract [en]

This study investigates the relation between individual language ability and neural semantic processing abilities. Our aim was to explore whether high-level language ability would correlate to decreased activation in language-specific regions or rather increased activation in supporting language regions during processing of sentences. Moreover, we were interested if observed neural activation patterns are modulated by semantic incongruency similarly to previously observed changes upon syntactic congruency modulation. We investigated 27 healthy adults with a sentence reading task which tapped language comprehension and inference, and modulated sentence congruency employing functional magnetic resonance imaging (fMRI). We assessed the relation between neural activation, congruency modulation, and test performance on a high-level language ability assessment with multiple regression analysis. Our results showed increased activation in the left-hemispheric angular gyrus extending to the temporal lobe related to high language ability. This effect was independent of semantic congruency, and no significant relation between language ability and incongruency modulation was observed. Furthermore, there was a significant increase of activation in the inferior frontal gyrus (IFG) bilaterally when the sentences were incongruent, indicating that processing incongruent sentences was more demanding than processing congruent sentences and required increased activation in language regions. The correlation of high-level language ability with increased rather than decreased activation in the left angular gyrus, a region specific for language processing, is opposed to what the neural efficiency hypothesis would predict. We can conclude that no evidence is found for an interaction between semantic congruency related brain activation and highlevel language performance, even though the semantic incongruent condition shows to be more demanding and evoking more neural activation.

Place, publisher, year, edition, pages
FRONTIERS MEDIA SA, 2016
Keywords
fMRI; semantic processing; congruency; sentence reading; language ability; inferior frontal gyrus; angular gyrus
National Category
Clinical Medicine Basic Medicine
Identifiers
urn:nbn:se:liu:diva-126805 (URN)10.3389/fnhum.2016.00110 (DOI)000371873000001 ()27014040 (PubMedID)
Note

Funding Agencies|Linkoping University; Linkoping University Hospital local funds

Available from: 2016-04-07 Created: 2016-04-05 Last updated: 2018-01-10
Warntjes, M. J., Engström, M., Tisell, A. & Lundberg, P. (2016). Modeling the Presence of Myelin and Edema in the Brain Based on Multi-Parametric Quantitative MRI. Frontiers in Neurology, 7(16)
Open this publication in new window or tab >>Modeling the Presence of Myelin and Edema in the Brain Based on Multi-Parametric Quantitative MRI
2016 (English)In: Frontiers in Neurology, ISSN 1664-2295, E-ISSN 1664-2295, Vol. 7, no 16Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to present a model that uses multi-parametric quantitative MRI to estimate the presence of myelin and edema in the brain. The model relates simultaneous measurement of R-1 and R-2 relaxation rates and proton density to four partial volume compartments, consisting of myelin partial volume, cellular partial volume, free water partial volume, and excess parenchymal water partial volume. The model parameters were obtained using spatially normalized brain images of a group of 20 healthy controls. The pathological brain was modeled in terms of the reduction of myelin content and presence of excess parenchymal water, which indicates the degree of edema. The method was tested on spatially normalized brain images of a group of 20 age-matched multiple sclerosis (MS) patients. Clear differences were observed with respect to the healthy controls: the MS group had a 79 mL smaller brain volume (1069 vs. 1148 mL), a 38 mL smaller myelin volume (119 vs. 157 mL), and a 21 mL larger excess parenchymal water volume (78 vs. 57 mL). Template regions of interest of various brain structures indicated that the myelin partial volume in the MS group was 1.6 +/- 1.5% lower for gray matter (GM) structures and 2.8 +/- 1.0% lower for white matter (WM) structures. The excess parenchymal water partial volume was 9 +/- 10% larger for GM and 5 +/- 2% larger for WM. Manually placed ROls indicated that the results using the template ROls may have suffered from loss of anatomical detail due to the spatial normalization process. Examples of the application of the method on high-resolution images are provided for three individual subjects: a 45-year-old healthy subject, a 72-year-old healthy subject, and a 45-year-old MS patient. The observed results agreed with the expected behavior considering both age and disease. In conclusion, the proposed model may provide clinically important parameters, such as the total brain volume, degree of myelination, and degree of edema, based on a single qMRI acquisition with a clinically acceptable scan time.

Place, publisher, year, edition, pages
FRONTIERS MEDIA SA, 2016
Keywords
quantitative magnetic resonance imaging; brain tissue modeling; myelin; edema; T-1 relaxation; T-2 relaxation; proton density
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-126132 (URN)10.3389/fneur.2016.00016 (DOI)000370433200002 ()26925030 (PubMedID)
Note

Funding Agencies|Linkoping University; County Council Ostergotland

Available from: 2016-03-15 Created: 2016-03-15 Last updated: 2017-11-30
Walter, S. A., Forsgren, M., Lundengård, K., Simon, R., Torkildsen Nilsson, M., Söderfeldt, B., . . . Engström, M. (2016). Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex. PLoS ONE, 11(3)
Open this publication in new window or tab >>Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex
Show others...
2016 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3Article in journal (Refereed) Published
Abstract [en]

Knowledge about the neural underpinnings of the negative blood oxygen level dependent (BOLD) responses in functional magnetic resonance imaging (fMRI) is still limited. We hypothesized that pharmacological GABAergic modulation attenuates BOLD responses, and that blood concentrations of a positive allosteric modulator of GABA correlate inversely with BOLD responses in the cingulate cortex. We investigated whether or not pure task-related negative BOLD responses were co-localized with pharmacologically modulated BOLD responses. Twenty healthy adults received either 5 mg diazepam or placebo in a double blind, randomized design. During fMRI the subjects performed a working memory task. Results showed that BOLD responses in the cingulate cortex were inversely correlated with diazepam blood concentrations; that is, the higher the blood diazepam concentration, the lower the BOLD response. This inverse correlation was most pronounced in the pregenual anterior cingulate cortex and the anterior mid-cingulate cortex. For subjects with diazepam plasma concentration > 0.1 mg/L we observed negative BOLD responses with respect to fixation baseline. There was minor overlap between cingulate regions with task-related negative BOLD responses and regions where the BOLD responses were inversely correlated with diazepam concentration. We interpret that the inverse correlation between the BOLD response and diazepam was caused by GABA-related neural inhibition. Thus, this study supports the hypothesis that GABA attenuates BOLD responses in fMRI. The minimal overlap between task-related negative BOLD responses and responses attenuated by diazepam suggests that these responses might be caused by different mechanisms.

Place, publisher, year, edition, pages
San Francisco, CA, United States: Public Library of Science, 2016
Keywords
quantitative magnetic resonance imaging; brain tissue modeling; myelin; edema; T-1 relaxation; T-2 relaxation; proton density
National Category
Neurosciences
Identifiers
urn:nbn:se:liu:diva-126192 (URN)10.1371/journal.pone.0148737 (DOI)000371434500011 ()26930498 (PubMedID)
Note

Funding agencies: Linkoping University; County Council of Ostergotland

Available from: 2016-03-18 Created: 2016-03-18 Last updated: 2018-01-10Bibliographically approved
Blystad, I., Håkansson, I., Tisell, A., Ernerudh, J., Smedby, Ö., Lundberg, P. & Larsson, E.-M. (2016). Quantitative MRI for Analysis of Active Multiple Sclerosis Lesions without Gadolinium-Based Contrast Agent. American Journal of Neuroradiology, 37(1), 94-100
Open this publication in new window or tab >>Quantitative MRI for Analysis of Active Multiple Sclerosis Lesions without Gadolinium-Based Contrast Agent
Show others...
2016 (English)In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 37, no 1, p. 94-100Article in journal (Refereed) Published
Abstract [en]

BACKGROUND AND PURPOSE: Contrast-enhancing MS lesions are important markers of active inflammation in the diagnostic work-up of MS and in disease monitoring with MR imaging. Because intravenous contrast agents involve an expense and a potential risk of adverse events, it would be desirable to identify active lesions without using a contrast agent. The purpose of this study was to evaluate whether pre-contrast injection tissue-relaxation rates and proton density of MS lesions, by using a new quantitative MR imaging sequence, can identify active lesions. MATERIALS AND METHODS: Forty-four patients with a clinical suspicion of MS were studied. MR imaging with a standard clinical MS protocol and a quantitative MR imaging sequence was performed at inclusion (baseline) and after 1 year. ROIs were placed in MS lesions, classified as nonenhancing or enhancing. Longitudinal and transverse relaxation rates, as well as proton density were obtained from the quantitative MR imaging sequence. Statistical analyses of ROI values were performed by using a mixed linear model, logistic regression, and receiver operating characteristic analysis. RESULTS: Enhancing lesions had a significantly (P < .001) higher mean longitudinal relaxation rate (1.22 0.36 versus 0.89 +/- 0.24), a higher mean transverse relaxation rate (9.8 +/- 2.6 versus 7.4 +/- 1.9), and a lower mean proton density (77 +/- 11.2 versus 90 +/- 8.4) than nonenhancing lesions. An area under the receiver operating characteristic curve value of 0.832 was obtained. CONCLUSIONS: Contrast-enhancing MS lesions often have proton density and relaxation times that differ from those in nonenhancing lesions, with lower proton density and shorter relaxation times in enhancing lesions compared with nonenhancing lesions.

Place, publisher, year, edition, pages
AMER SOC NEURORADIOLOGY, 2016
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-124482 (URN)10.3174/ajnr.A4501 (DOI)000367466500019 ()26471751 (PubMedID)
Note

Funding Agencies|National Science and Engineering Research Council; University of Linkoping; University Hospital Research Funds

Available from: 2016-02-02 Created: 2016-02-01 Last updated: 2017-11-16
Forsgren, M., Norén, B., Kihlberg, J., Dahlqvist Leinhard, O., Kechagias, S. & Lundberg, P. (2015). Comparing hepatic 2D and 3D magnetic resonance elastography methods in a clinical setting – Initial experiences. European Journal of Radiology Open, 2, 66-70
Open this publication in new window or tab >>Comparing hepatic 2D and 3D magnetic resonance elastography methods in a clinical setting – Initial experiences
Show others...
2015 (English)In: European Journal of Radiology Open, E-ISSN 2352-0477, Vol. 2, p. 66-70Article in journal (Refereed) Published
Abstract [en]

Purpose

Continuous monitoring of liver fibrosis progression in patients is not feasible with the current diagnostic golden standard (needle biopsy). Recently, magnetic resonance elastography (MRE) has emerged as a promising method for such continuous monitoring. Since there are different MRE methods that could be used in a clinical setting there is a need to investigate whether measurements produced by these MRE methods are comparable. Hence, the purpose of this pilot study was to evaluate whether the measurements of the viscoelastic properties produced by 2D (stiffness) and 3D (elasticity and ‘Gabs,Elastic’) MRE are comparable.

Materials and methods

Seven patients with diffuse or suspect diffuse liver disease were examined in the same day with the two MRE methods. 2D MRE was performed using an acoustic passive transducer, with a 1.5 T GE 450 W MR system. 3D MRE was performed using an electromagnetic active transducer, with a 1.5 T Philips Achieva MR system. Finally, mean viscoelastic values were extracted from the same anatomical region for both methods by an experienced radiologist.

Results

Stiffness correlated well with the elasticity, R2 = 0.96 (P < 0.001; slope = 1.08, intercept = 0.61 kPa), as well as with ‘Gabs,ElasticR2 = 0.96 (P < 0.001; slope = 0.95, intercept = 0.28 kPa).

Conclusion

This pilot study shows that different MRE methods can produce comparable measurements of the viscoelastic properties of the liver. The existence of such comparable measurements is important, both from a clinical as well as a research perspective, since it allows for equipment-independent monitoring of disease progression.

Place, publisher, year, edition, pages
Elsevier, 2015
Keywords
Liver; Rheology; Elastography; Fibrosis; MRE; MRI
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-119848 (URN)10.1016/j.ejro.2015.04.001 (DOI)
Available from: 2015-06-26 Created: 2015-06-26 Last updated: 2018-07-18Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-8661-2232

Search in DiVA

Show all publications