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  • 1.
    Black, David
    et al.
    Medical Image Computing, University of Bremen; Jacobs University, Bremen; Fraunhofer MEVIS, Bremen, Germany.
    Hahn, Horst
    Jacobs University, Bremen; Fraunhofer, MEVIS, Germany.
    Kikinis, Ron
    Brigham and Women's Hospital and Harvard Medical School, Boston, USA.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Haj Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Auditory display for Fluorescence-guided open brain tumor surgery2018Ingår i: International Journal of Computer Assisted Radiology and Surgery, ISSN 1861-6410, E-ISSN 1861-6429, Vol. 13, nr 1, s. 25-35Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE:

    Protoporphyrin (PpIX) fluorescence allows discrimination of tumor and normal brain tissue during neurosurgery. A handheld fluorescence (HHF) probe can be used for spectroscopic measurement of 5-ALA-induced PpIX to enable objective detection compared to visual evaluation of fluorescence. However, current technology requires that the surgeon either views the measured values on a screen or employs an assistant to verbally relay the values. An auditory feedback system was developed and evaluated for communicating measured fluorescence intensity values directly to the surgeon.

    METHODS:

    The auditory display was programmed to map the values measured by the HHF probe to the playback of tones that represented three fluorescence intensity ranges and one error signal. Ten persons with no previous knowledge of the application took part in a laboratory evaluation. After a brief training period, participants performed measurements on a tray of 96 wells of liquid fluorescence phantom and verbally stated the perceived measurement values for each well. The latency and accuracy of the participants' verbal responses were recorded. The long-term memorization of sound function was evaluated in a second set of 10 participants 2-3 and 7-12 days after training.

    RESULTS:

    The participants identified the played tone accurately for 98% of measurements after training. The median response time to verbally identify the played tones was 2 pulses. No correlation was found between the latency and accuracy of the responses, and no significant correlation with the musical proficiency of the participants was observed on the function responses. Responses for the memory test were 100% accurate.

    CONCLUSION:

    The employed auditory display was shown to be intuitive, easy to learn and remember, fast to recognize, and accurate in providing users with measurements of fluorescence intensity or error signal. The results of this work establish a basis for implementing and further evaluating auditory displays in clinical scenarios involving fluorescence guidance and other areas for which categorized auditory display could be useful.

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  • 2.
    Brydegaard, Mikkel
    et al.
    Department of Physics, Lund University.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Department of Physics, Lund University.
    Photobleaching-Insensitive Fluorescence Diagnostics in Skin and Brain Tissue2011Ingår i: IEEE Photonics Journal, ISSN 1943-0655, Vol. 3, nr 3, s. 407-421Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    In this paper, we investigate the possibility of using accurate prediction models for the prediction of protoporphyrin bleaching dynamics to achieve photobleaching-insensitive methods to improve the evaluation of data in an existing clinical fluorescence-guided resection technique. To simulate the scenario, measurements were carried out in vivo on skin of healthy volunteers using a compact fiber-based fluorescence spectroscopy system. We have developed an effective method for the parameterization of sequences of bleaching spectra. We analyze convergence and decay rates with respect to initial conditions and excitation irradiance. We also discuss the consequences and the potential for bleaching-insensitive measurements and their applicability in a few examples from in vivo open brain surgery.

  • 3.
    Haj Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Medicinska fakulteten.
    Milos, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US. Neurokirurgi.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Optical Guidance for Brain Tumor Stereotactic Biopsy2017Konferensbidrag (Refereegranskat)
  • 4. Beställ onlineKöp publikationen >>
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence Spectroscopy for Quantitative Demarcation of Glioblastoma Using 5-Aminolevulinic Acid2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Total resection of glioblastoma, the highly malignant brain tumor, is difficult to accomplish due to its diffuse growth and similarity to the surrounding brain tissue. A total resection is proven to increase patient survival. The aim of this thesis was to evaluate fiber-optical based fluorescence spectroscopy for quantitative demarcation of malignant brain tumors during the surgery. Five-aminolevulinic acid (5-ALA) was used as a fluorescence contrast agent that accumulated as protoporphyrin IX (PpIX) in the tumor.

    The method was evaluated at the Department of Neurosurgery, Linköping University Hospital. The patients (n = 22) received an oral dose of 5 mg/kg body weight 5-ALA two hours prior to craniotomy. Measurements with a developed fluorescence spectroscopy system were performed under the general procedure of surgery. The collected fluorescence spectra were quantified by defining a fluorescence ratio and the main challenges of measuring and quantifying spectra were investigated. The fluorescence ratio was compared to visual diagnosis of the surgeon, histopathological examination and ultrasound-based neuronavigation. The main challenges of using a fluorescence spectroscopy system in the operating room were the disturbing ambient light, photobleaching and blood interference which affect the signal quantification. The superimposition of ambient light was removed by modulating the system.

    Using principal component analysis (PCA) the photobleaching sequences could be described by three spectral components of autofluorescence, PpIX fluorescence and blue-shift. To investigate the photobleaching induced prior to the measurements, a dynamic model was developed based on the PCA derived spectral components. Modulation and increased power of the excitation light resulted in a faster photobleaching; however, photobleaching was saturated at higher excitation powers. The system was adjusted to induce minimal photobleaching. In addition, effect of blood absorption on the fluorescence spectrum was investigated experimentally by placing blood drops on skin and theoretically by using Beer-Lambert law. The theoretical model was used to compensate for the distorted fluorescence ratio. According to the theoretical model of blood interference, a total 300 µm blood layer blocked the brain fluorescence signal totally and when the fluorescence signal was partially blocked, the fluorescence ratio was overestimated. The fluorescence ratio was corrected for blood layers thinner than 50 µm.

    The tissue in and around the tumor was categorized into necrosis, low and high grade tumor and gliosis. The median fluorescence ratio confirmed with histopathological examination (n = 45) had a lower fluorescence ratio for low grade malignancies (0.3) than high grade malignancies (2.4) (p < 0.05). Gliosis (1.6) and necrosis (1.0) showed a moderate fluorescence ratio. Ultrasound-based navigation in combination with fluorescence spectroscopy showed improvement in the results; however, a more extensive study is needed to confirm benefits of the method combination. In conclusion, fluorescence spectroscopy of 5-ALA induced PpIX provided an objective method for differentiating tumor from the healthy tissue intra-operatively. Fluorescence ratios were indicative of tissue type and tumor malignancy degree.

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    Fluorescence Spectroscopy for Quantitative Demarcation of Glioblastoma Using 5-Aminolevulinic Acid
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  • 5.
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Optical Coherence Tomography for 3D Cancer Imaging2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Optical coherence tomography (OCT) is an advanced optical imaging technology for imaging material based on their optical scattering properties. OCT provides high-resolution 2D (en face or cross-sectional) and 3D images from the surface and subsurface tissue microstructures within a few mm depth. The first article on OCT was published in 1991 by D. Huang et. al. [1]. More than 15000 articles have been published since 1991 on different applications of OCT. However, the technique has so far entered the clinical routine only within ophthalmology and cardiovascular imaging in which the majority of the articles have been published [2]. OCT is a capable technology with great potentials for further translational research and implementation in additional clinical fields. One potential application of OCT is within cancer detection intraoperatively or post operatively for providing an on-site fast diagnosis. In this study, OCT’s ability to differentiate histology and pathology for application in tissue identification, pathological diagnosis and cancer staging was investigated.

    Material and Method:

    The technology uses near infrared or infrared light for imaging tissue structures that havedifferent optical scattering properties. The technique is based on low coherence interferometryand measures the backscattered light from the tissue. The scanning dimensions and resolutions are dependent on the type of the OCT system. In this study a TELESTO IITM system (Thorlabs, Inc., NJ, USA) was used. The maximum lateral and axial resolution of the system were 13 and 5.5 μm, respectively. A total of eleven patients undergoing brain, thyroid and parathyroid surgery were included in the study.

    Results:

    Figure 1 shows a 3D scan of the fingertip taken by the described OCT system as an example. The skin layers (epidermis and dermis) including the fingerprint and a sweat gland (the spiral structure) are visible. Various tissue type specimens involved in thyroid and parathyroid surgeries and brain tumor surgery were evaluated.

  • 6.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Lund University.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Evaluation of a Fiber-Optic Based Pulsed Laser System for Fluorescence Spectroscopy2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    A fiber optic based continous wave laser setup has been developed to record the 5-aminolevulinic (5-ALA) induced Protoporfyrin IX (PpIX) fluorescence signals from cerebral gliomas. To reduce the energy delivered to the tissue as well as suppression of the ambient lamp artifact from the recorded spectra, a pulsed laser setup has been developed and evaluated. This setup has been calibrated and first evaluations were performed on the 5-ALA treated skin showing PpIX fluorescence peaks from the ALA treated skin at 635 and 704 nm wavelengths. The system controls laser pulses through a computer interface and labview software package. Pulses as short as 50 ms over a period time of 500 ms are generated and optimally detected. The results from primary measurements on skin show an effective suppression of room fluorescent lamp artifact from the recorded spectra.

  • 7.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Behm, Pascal
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska högskolan. University of Applied Sciences in Northwest Switzerland.
    Shabo, Ivan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence spectroscopy using indocyanine green for lymph node mapping2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    The principles of cancer treatment has for years been radical resection of the primary tumor. In the oncologic surgeries where the affected cancer site is close to the lymphatic system, it is as important to detect the draining lymph nodes for metastasis (lymph node mapping). As a replacement for conventional radioactive labeling, indocyanine green (ICG) has shown successful results in lymph node mapping; however, most of the ICG fluorescence detection techniques developed are based on camera imaging. In this work, fluorescence spectroscopy using a fiber-optical probe was evaluated on a tissue-like ICG phantom with ICG concentrations of 6-64 μM and on breast tissue from five patients. Fiber-optical based spectroscopy was able to detect ICG fluorescence at low intensities; therefore, it is expected to increase the detection threshold of the conventional imaging systems when used intraoperatively. The probe allows spectral characterization of the fluorescence and navigation in the tissue as opposed to camera imaging which is limited to the view on the surface of the tissue

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  • 8.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Gimm, Oliver
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för Kirurgi, Ortopedi och Onkologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Höög, Anders
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Johansson, Kenth
    Landstinget i Kalmar län och Sahlgrenska universitetssjukhus, Västra Götalandsregion.
    Optiska metoder för identifiering av bisköldkörtel och sköldkörtel2017Konferensbidrag (Refereegranskat)
    Abstract [sv]

    Identifiering av bisköldkörtlar är viktigt vid sköldkörtel- och bisköldkörtelkirurgi och kan vara svårt då de liknar omgivande vävnad såsom fett och lymfkörtlar. Peroperativ detektering av dessa vävnader kan förbättra möjligheten att bota patienter med hyperparathyroidism och minska risken för bisköldkörtelskador vid thyroideakirurgi. Optiska metoder är potentiella tekniker för att möjliggöra detta. Optiska tekniker utvärderades på vävnadsprover från patienter vid bisköldkörtel- och sköldkörteloperation. Teknikerna bestod av nära infraröd fluorescens (NIR) spektroskopi och optisk koherenstomografi (OCT) som ger en bild av vävnadens mikrostruktur liknande till ultraljud med högre upplösning (10 μm).

  • 9.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Kistler, Benjamin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. University of Applied Sciences in Northwest Switzerland.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Development and characterization of a brain tumor mimicking fluorescence phantom   2014Ingår i: Proceedings of SPIE, the International Society for Optical Engineering, ISSN 0277-786X, E-ISSN 1996-756X, Vol. 8945, s. 1-6, artikel-id 894505Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fluorescence guidance using 5-aminolevulinic acid (5-ALA) for brain tumor resection is a recent technique applied to the highly malignant brain tumors. Five-ALA accumulates as protoporphyrin IX fluorophore in the tumor cells in different concentrations depending on the tumor environment and cell properties. Our group has developed a fluorescence spectroscopy system used with a hand-held probe intra-operatively. The system has shown improvement of fluorescence detection and allows quantification that preliminarily correlates with tumor malignancy grade during surgery. However, quantification of fluorescence is affected by several factors including the initial fluorophore concentration, photobleaching due to operating lamps and attenuation from the blood. Accordingly, an optical phantom was developed to enable controlled fluorescence measurements and evaluation of the system outside of the surgical procedure. The phantom mimicked the optical properties of glioma at the specific fluorescence excitation wavelength when different concentrations of the fluorophore were included in the phantom. To allow evaluation of photobleaching, kinetics of fluorophore molecules in the phantom was restricted by solidifying the phantoms. Moreover, a model for tissue autofluorescence was added. The fluorescence intensity’s correlation with fluorophore concentration in addition to the photobleaching properties were investigated in the phantoms and were compared to the clinical data measured on the brain tumor.

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  • 10.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Lowndes, Shannely
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska högskolan.
    Salerud, Göran
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Blood interference in fiber-optical based fluorescence guided resection of glioma using 5-aminolevulinic acid2011Ingår i: Photonic Therapeutics and Diagnostics VII / [ed] Nikiforos Kollias; Bernard Choi; Haishan Zeng; Hyun Wook Kang; Bodo E. Knudsen; Brian J. Wong; Justus F. R. Ilgner; Kenton W. Gregory; Guillermo J. Tearney; Laura Marcu; Henry Hirschberg; Steen J. Madsen; Andreas Mandelis; Anita Mahadevan-Jansen; E. Duco Jansen, SPIE - International Society for Optical Engineering, 2011, s. 78833R-1-78833R-10Konferensbidrag (Refereegranskat)
    Abstract [en]

    Fluorescence guidance in brain tumor resection is performed intra-operatively where bleeding is included. When using fiber-optical probes, the transmission of light to and from the tissue is totally or partially blocked if a small amount of blood appears in front of the probe. Sometimes even after rinsing with saline, the remnant blood cells on the optical probe head, disturb the measurements. In such a case, the corresponding spectrum cannot be reliably quantified and is therefore discarded. The optimal case would be to calculate and take out the blood effect systematically from the collected signals. However, the first step is to study the pattern of blood interference in the fluorescence spectrum. In this study, a fiber-optical based fluorescence spectroscopy system with a laser excitation light of 405 nm (1.4 J/cm2) was used during fluorescence guided brain tumor resection using 5-aminolevulinic acid (5-ALA). The blood interference pattern in the fluorescence spectrum collected from the brain was studied in two patients. The operation situation was modeled in the laboratory by placing blood drops from the finger tip on the skin of forearm and the data was compared to the brain in vivo measurements. Additionally, a theoretical model was developed to simulate the blood interference pattern on the skin autofluorescence. The blood affects the collected fluorescence intensity and leaves traces of oxy and deoxy-hemoglobin absorption peaks. According to the developed theoretical model, the autofluorescence signal is considered to be totally blocked by an approximately 500 μm thick blood layer.

  • 11.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Milos, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hildesjö, Camilla
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Fluorescence spectroscopy and optical coherence tomography for brain tumor detection2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Resection of brain tumor is a challenging task as the tumor does not have clear borders and the malignant types specifically have often a diffuse and infiltrative pattern of growth. Recently, neurosurgical microscopes have been modified to incorporate fluorescence modules for detection of tumor when 5-aminolevulinic acid (5-ALA) is used as a contrast. We have in combination with the fluorescence microscopes implemented and evaluated a fluorescence spectroscopy based handheld probe for detecting the 5-aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) in the gliomas in 50 patients intraoperatively. The results show a significantly high sensitivity for differentiating tumor from the healthy tissue and distinguished fluorescence intensity levels in the tumor cell infiltration zone around the tumor. However, knowledge on association of the quantified fluorescence signals specifically in the intermediate inflammatory zone with the infiltrative tumor cells can be complemented with volumetric tissue imaging and a higher precision histopathological analysis. In this work, a spectral domain optical coherence tomography (OCT) system with central wavelength of 1325nm has been used to image the tissue volume that the fluorescence is collected from and is evaluated against histopathological analysis for a higher precision slicing. The results show that although healthy brain has a homogenous microstructure in the OCT images, the brain tumor shows a distinguished texture in the images correlated with the PpIX fluorescence intensity and histopathology.

  • 12.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Milos, Peter
    Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hildesjö, Camilla
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Detection of brain tumor using fluorescence and optical coherence tomography2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Resection of brain tumor is a challenging task as the tumor does not have clear borders and the malignant types specifically have often a diffuse and infiltrative pattern of growth. We have previously implemented and evaluated a fluorescence spectroscopy based handheld probe for detecting the 5-aminolevulinic acid induced protoporphyrin IX (PpIX) in the gliomas. To add another dimension to the brain tumor detection and volumetric analysis of the tissue that exhibits fluorescence, optical coherence tomography was investigated on tumor specimens.

    Material and Methods:

    A fluorescence microscopy and a spectroscopy system as reported previously were used for detecting the fluorescence signals [1, 2]. A total of 50 patients have been included for intraoperative assessment of the tumor borders using the fluorescence techniques. A spectral domain OCT imaging system (TELESTO II, Thorlabs, Inc., NJ, USA) with central wavelength of 1325 nm was used to study the tissue microstructure post operatively. The system has a resolution of 13 and 5.5 μm in the lateral and axial directions, respectively. Tissue specimens from three patients undergoing brain tumor surgery were studied using the OCT system.

    Results and Conclusion:

    Using fluorescence spectroscopy the tumor could be detected with a sensitivity of 0.84 which was significantly higher than that of the surgical microscope (0.30). Brain tissue appeared rather homogeneous in the OCT images however the highly malignant tissue showed a clear structural difference from the non-malignant or low malignant brain tumor tissue which could be related to the fluorescence signal intensities.

  • 13.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Medicinska fakulteten.
    Petersson, Pernilla
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Gimm, Oliver
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Shabo, Ivan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Optical Coherence Tomography for Pathological Analysis of Thyroid2016Konferensbidrag (Refereegranskat)
  • 14.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US.
    Andersson-Engel, Stefan
    Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence guided resection of glioblastoma multiforme using an optical touch pointer-Clinical evaluation2010Konferensbidrag (Refereegranskat)
  • 15.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Department of Physics, Lund University.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fiber optic based fluorescence guided cerebral glioma resection using a pulsed laser setup2008Konferensbidrag (Refereegranskat)
  • 16.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Lund University of Technology.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fiber optic based fluorescence spectroscopy on glioblastoma multiforme using 5-aminolevulinic acid - Preliminary clinical results2009Konferensbidrag (Övrigt vetenskapligt)
  • 17.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Optical Touch Pointer for Fluorescence Guided Glioblastoma Resection Using 5-Aminolevulinic Acid2010Ingår i: Lasers in Surgery and Medicine, ISSN 0196-8092, E-ISSN 1096-9101, Vol. 42, nr 1, s. 9-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and Objective

    Total tumor resection in patients with glioblastoma multiforme (GBM) is difficult to achieve due to the tumor's infiltrative way of growing and morphological similarity to the surrounding functioning brain tissue. The diagnosis is usually subjectively performed using a surgical microscope. The objective of this study was to develop and evaluate a hand-held optical touch pointer using a fluorescence spectroscopy system to quantitatively distinguish healthy from malignant brain tissue intraoperatively.

    Study Design/Materials and Methods

    A fluorescence spectroscopy system with pulsed modulation was designed considering optimum energy delivery to the tissue, minimal photobleaching of PpIX and omission of the ambient light background in the operating room (OR). 5-Aminolevulinic acid (5-ALA) of 5 mg/kg body weight was given to the patients with a presumed GBM prior to surgery. During the surgery a laser pulse at 405 nm was delivered to the tissue. PpIX in glioblastoma tumor cells assigned with peaks at 635 and 704 nm was detected using a fiber optical probe.

    Results/Conclusion

    By using the pulsed fluorescence spectroscopy, PpIX fluorescence is quantitatively detected in the GBM. An effective suppression of low power lamp background from the recorded spectra in addition to a significant reduction of high power surgical lights is achieved.

    Ladda ner fulltext (pdf)
    fulltext
  • 18.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgisk klinik.
    Andersson-Engels, Stefan
    Dept. of Physics, Lund University, Lund, Sweden.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Photobleaching behavior of protoporphyrin IX during 5-aminolevulinic acid marked glioblastoma detection2009Ingår i: Photonic Therapeutics and Diagnostics V / [ed] Nikiforos Kollias; Bernard Choi; Haishan Zeng; Reza S. Malek; Brian J. Wong; Justus F. R. Ilgner; Kenton W. Gregory; Guillermo J. Tearney; Laura Marcu; Henry Hirschberg; Steen J. Madsen, SPIE - International Society for Optical Engineering, 2009, s. 716131-1-716131-8Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The highly malignant brain tumor, glioblastoma multiforme (GBM), is difficult to fully delineate during surgical resection due to its infiltrative ingrowth and morphological similarities to surrounding functioning brain tissue. Selectiveness of GBM to 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (PpIX) is reported by other researchers to visualize tumor margins under blue light microscopy. To allow objective detection of GBM, a compact and portable fiber optic based fluorescence spectroscopy system is developed. This system is able to deliver excitation laser light (405 nm) in both the continuous and pulsed mode. PpIX fluorescence peaks are detected at 635 and 704 nm, using a fiber-coupled spectrometer. It is necessary to optimize the detection efficiency of the system as the PpIX quickly photobleaches during the laser illumination. A light dose of 2.5 mJ (fluence rate = 9 mJ/mm2) is experimentally approved to excite an acceptable level of fluourescence signal arising from glioblastoma. In pulsed illumination mode, an excitation dose of 2.5 mJ, with a dark interval of 0.5 s (duty cycle 50%) shows a significantly shorter photobleaching time in comparison to the continuous illumination mode with the same laser power (p < 0.05). To avoid photobleaching (the remaining signal is more than 90% of its initial value) when measuring with 2.5 mJ delivered energy, the time for continuous and pulsed illumination should be restricted to 2.5 and 1.1 s, respectively.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 19.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi.
    Milos, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Stereotactic Brain Tumor Optical Biopsy2018Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    To provide guidance for targeting diagnostic tumor tissue and to avoid vessel rupture during the biopsy procedure an application specific fiber optic probe was devel-oped. The setup incorporated an in-house developed fluorescence spectroscopy system for 5-aminolevulinic acid (5-ALA) induced protopophyrin IX (PpIX) for detection in the tumor, and laser Doppler flowmeter (LDF) system for measurement of blood perfusion. Fluorescence and blood flow were recorded millimeter-wise towards the pre-calculated target. In conclusion, the optical probe made real-time detection of tumor possible and has a potential for vessel detection during the biopsy procedures. Moreover, the PpIX fluorescence, autofluorescence and blood flow in the tumor could be studied at precise positions in the brain and the tumor. In the next step, further anal-ysis will be added.

  • 20.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Low dose 5-aminolevulinic acid: Implications in spectroscopic measurements during brain tumor surgery2015Ingår i: Photodiagnosis and Photodynamic Therapy, ISSN 1572-1000, E-ISSN 1873-1597, Vol. 12, nr 2, s. 209-214Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    Using 5-aminolevulinic acid (ALA) as an intraoperative fluorescence contrast has been proven to improve the resection of glioblastoma and contribute to prolonged patient survival. ALA accumulates as protoporphyrin IX (PpIX) in the tumor cells and is administered in an advised dose of 20 mg/kg body weight (b.w.) for brain tumor resection using fluorescence surgical microscopes. PpIX fluorescence availability and intensities of a four folds lower ALA dose (5 mg/kg b.w.) has been investigated in glioblastomas and skin using a spectroscopy system adapted for surgical guidance.

    Methods

    A total of 30 adult patients diagnosed with high grade gliomas were included in the analysis. ALA was orally administered in doses of 5 mg/kg b.w. (n = 15) dissolved in orange juice or 20 mg/kg b.w. (n = 15) dissolved in water. A fluorescence spectroscopy system with a handheld fiber-optical probe was used for performing the quantitative fluorescence measurements.

    Results

    The binominal comparison of the diagnostic performance parameters showed no significant statistical difference (p > 0.05). The median fluorescence values in tumor were 2-3 times higher for the high ALA dose group. No PpIX was detected in the skin of the patients in the low dose group (0/4) while PpIX was detected in the skin of the majority of the patients in the high ALA dose group (13/14).

    Conclusions

    Application of 5 mg/kg ALA was evaluated as equally reliable as the higher dose regarding the diagnostic performance when guidance was performed using a spectroscopic system. Moreover, no PpIX was detected in the skin of the patients.

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    fulltext
  • 21.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Richter, Johan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Kobayashi Frisk, Lisa
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Milos, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Fluorescence Guidance for Brain Tumor Biopsies2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    To provide guidance during stereotactic biopsy in brain tumors, fluorescence spectroscopy was used in ten patients. It was shown that the fiber optical probe could provide real-time guidance with clear fluorescence in all patients.

  • 22.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Milos, Peter
    Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    5-ALA fluorescence and laser Doppler flowmetry for guidance in a stereotactic brain tumor biopsy2018Ingår i: Biomedical Optics Express, E-ISSN 2156-7085, Vol. 9, nr 5, s. 2284-2296Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A fiber optic probe was developed for guidance during stereotactic brain biopsy procedures to target tumor tissue and reduce the risk of hemorrhage. The probe was connected to a setup for the measurement of 5-aminolevulinic acid (5-ALA) induced fluorescence and microvascular blood flow. Along three stereotactic trajectories, fluorescence (n = 109) and laser Doppler flowmetry (LDF) (n = 144) measurements were done in millimeter increments. The recorded signals were compared to histopathology and radiology images. The median ratio of protoporphyrin IX (PpIX) fluorescence and autofluorescence (AF) in the tumor was considerably higher than the marginal zone (17.3 vs 0.9). The blood flow showed two high spots (3%) in total. The proposed setup allows simultaneous and real-time detection of tumor tissue and microvascular blood flow for tracking the vessels.

    Ladda ner fulltext (pdf)
    fulltext
  • 23.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Medicinska fakulteten.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Milos, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Optical guidance for stereotactic brain tumor biopsy procedures-preliminary clinical evaluation2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    During stereotactic biopsy on suspected tumors in the brain, tissue samples are harvested to determine the malignancy. To provide guidance for finding the diagnostic tumor sites and to avoid vessel rupture, an application specific probe was developed. The setup incorporated spectroscopy for detection of 5-aminolevulinic acid induced protoporphyrin (PpIX) fluorescence and blood flow using laser Doppler flowmetry. The PpIX fluorescence was significantly different in the tumor compared to the gliotic marginal zone (p < 0.05). In conclusion, the systems made real-time tumor detection and vessel tracking possible. Moreover, the autofluorescence and blood perfusion could be studied in the tumor.

  • 24.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Olivecrona, Magnus
    Department of Neurosurgery, Umeå University.
    Hillman, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Neurokirurgi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Experimentell patologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence guided spectroscopy versus fluorescence microscopy for brain tumor resection2013Konferensbidrag (Övrigt vetenskapligt)
  • 25.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence spectroscopy for ALA-guided glioblastoma resection using a fiber-optical probe2012Konferensbidrag (Refereegranskat)
  • 26.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Medicinska fakulteten.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Medicinska fakulteten.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Photodiagnostics in Brain Tumor Surgery2014Ingår i: Medicinteknikdagarna, Göteborg, 14-16 oktober, 2014: Sammanfattningar, Göteborg: Svensk förening för medicinsk teknik och fysik , 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Since getting approved for clinical application in neurosurgery 5-aminolevulinic acid (ALA), that is a fluorescence contrast agent, has attracted the interest of many neurosurgical clinics to implement it in their surgical routine. ALA naturally exists in the body and the external administration of the substance induces accumulation of a fluorophore known as protoporphyrin IX (PpIX) in the malignant cells due to a broken blood brain barrier and the altered enzyme levels in the brain tumor. The detection and visualization of PpIX in the clinical routine is conventionally performed using a modified neuro surgical microscope. As a complementary technique for detection of ALA-induced fluorescence and to perform objective and quantitative measurements, our group has developed a spectroscopy system adapted to the equipment in the operating room. The system includes a hand-held fiber optic probe which can be integrated in the neuronavigation and stereotactic systems. The main advantages of the system are the ease of use, high sensitivity, quantitative fluorescence detection and the possibility of applying a low dose of fluorescence contrast agent while obtaining equally reliable results as with the high dose. In this contribution we present our experience, gains and challenges from implementation of the system during brain tumor surgery in forty adult patients. The methods and systems are currently being adapted for implementation during operations of pediatric brain tumors.

  • 27.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Hälsouniversitetet.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Quantitative ALA photodiagnostics in Neurosurgery2014Konferensbidrag (Övrigt vetenskapligt)
  • 28.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Salerud, Göran
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Compensation of blood interference in fiber-optical based fluorescence guided resection of brain tumor2011Konferensbidrag (Refereegranskat)
  • 29.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Stepp, Herbert
    Ludwig Maximilians Universitet, München.
    Markwardt, Niklas
    Ludwig Maximilians Universitet, München.
    Gimm, Oliver
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Shabo, Ivan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Region Östergötland, Centrum för kirurgi, ortopedi och cancervård, Kirurgiska kliniken US.
    Optical biopsy during thyroid and parathyroid surgery2015Konferensbidrag (Refereegranskat)
  • 30.
    Haj-Hosseini, Neda
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Optical Coherence Tomography as a Future Modality in Digital Pathology2015Konferensbidrag (Övrigt vetenskapligt)
  • 31.
    Johansson, Johannes
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Blomstedt, P.
    Department of Neurosurgery University Hospital, Umeå, Sweden.
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Bergenheim, A. T.
    Department of Neurosurgery University Hospital, Umeå, Sweden.
    Hariz, M. I.
    Department of Neurosurgery University Hospital, Umeå, Sweden.
    Eriksson, Ola
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Wårdell, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Combined electric impedance and optical diffuse reflectance measurements for navigation aid in deep brain surgery2008Ingår i: XVIII Congress of the European Society for Stereotactic and Functional Neurosurgery,2008, 2008Konferensbidrag (Övrigt vetenskapligt)
  • 32.
    Johansson, Johannes D.
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Blomstedt, Patric
    Department of Neurosurgery, Norrland´s University Hospital, Umeå, Sweden.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Bergenheim, Tommy
    Department of Neurosurgery, Norrland´s University Hospital, Umeå, Sweden.
    Eriksson, Ola
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Combined diffuse light reflectance and electric impedance measurements for navigation aid in deep brain surgery2009Ingår i: Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372, Vol. 87, nr 2, s. 105-113Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aim: The aim of this study is to investigate reflected light intensity combined with impedance for navigation aid during stereotactic neurosurgery.

    Methods: During creation of 21 trajectories for stereotactic implantation of deep brain stimulation electrodes in the globus pallidus internus or subthalamus (zona incerta or subthalamic nucleus), impedance at 512 kHz and reflected light intensity at 780 nm were measured continuously and simultaneously with a radio frequency electrode containing optical fibres. The signals were compared with anatomy determined from pre- and postoperative MRI and CT. The measurements were performed within minutes and signal analysis was done post-operatively.

    Results: Reflected light intensity was low from cortex, lateral ventricle, caudate nucleus and putamen. It was intermediate from globus pallidus and thalamus while it was high from subcortical white matter, internal capsule and the subthalamus. The electric impedance was less consistent but generally low in the cortex, intermediate in subcortical white matter, the putamen, the globus pallidus and the thalamus and high in the internal capsule and the subthalamus.

    Conclusion: Reflected light intensity and electric impedance give complementary information about passed tissue and the combination seems promising for navigation aid during stereotactic neurosurgery.

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  • 33.
    Maintz, Michaela
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik.
    Black, David
    Fraunhofer MEVIS Institute for Digital Medicine in Bremen, Germany.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik.
    Auditory and Visual User Interface for Optical Guidance During Stereotactic Brain Tumor Biopsies2019Ingår i: Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, IEEE conference proceedings, 2019, s. 1981-1984Konferensbidrag (Refereegranskat)
    Abstract [en]

    During stereotactic brain tumor biopsies, the detection of protoporphyrin IX (PpIX) fluorescence and microvascular perfusion using laser Doppler flowmetry (LDF) with a handheld fiber optic probe allows the identification of tumor tissue while decreasing the risk of intracranial hemorrhage. Neurosurgeons performing this procedure usually view the measurement values on a screen. When their visual focus is directed at the surgical site, they require an assistant to verbally relay the values. An auditory and visual user interface (UI), which displays measurement values accurately and allows fast and intuitive signal recognition, can improve this procedure. This paper experimentally evaluates an auditory and visual UI for providing real-time measurement feedback during stereotactic brain tumor biopsies. In a user study (n = 15), the accuracy of auditory and visual response was determined using function response tests, and user acceptance was evaluated. The auditory signals proved to be intuitive and easy to recognize and remember. The visual display of measurement values was easy to understand and facilitated the user’s decision-making process. Moreover, the UI exhibited high user acceptance.

  • 34.
    Markwardt, Niklas
    et al.
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany .
    Götz, Marcus
    MRC Systems GmbH, Heidelberg, Germany.
    Haj Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Medicinska fakulteten.
    Hollnburger, Bastian
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany .
    Sroka, Ronald
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany .
    Stepp, Herbert
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany .
    Zelenkov, Petr
    N.N. Burdenko Neurosurgical Institute, Russian Federation.
    Rühm, Adrian
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany .
    Detection limits of 405 nm and 633 nm excited PpIX fluorescence for brain tumor detection during stereotactic biopsy2016Ingår i: Biophotonics: Photonic Solutions for Better Health Care V: Proceedings of SPIE / [ed] Jürgen Popp, Valery V. Tuchin, Dennis L. Matthews, Francesco S. Pavone, Brussels: SPIE - International Society for Optical Engineering, 2016, Vol. 9887, artikel-id 98872ZKonferensbidrag (Refereegranskat)
    Abstract [en]

    5-aminolevulinic-acid-(5-ALA)-induced protoporphyrin IX (PpIX) fluorescence may be used to improve stereotactic brain tumor biopsies. In this study, the sensitivity of PpIX-based tumor detection has been investigated for two potential excitation wavelengths (405 nm, 633 nm). Using a 200 μm fiber in contact with semi-infinite optical phantoms containing ink and Lipovenös, PpIX detection limits of 4.0 nM and 200 nM (relating to 1 mW excitation power) were determined for 405 nm and 633 nm excitation, respectively. Hence, typical PpIX concentrations in glioblastomas of a few μM should be well detectable with both wavelengths. Additionally, blood layers of selected thicknesses were placed between fiber and phantom. Red excitation was shown to be considerably less affected by blood interference: A 50 μm blood layer, for instance, blocked the 405- nm-excited fluorescence completely, but reduced the 633-nm-excited signal by less than 50%. Ray tracing simulations demonstrated that - without blood layer - the sensitivity advantage of 405 nm rises for decreasing fluorescent volume from 50-fold to a maximum of 100-fold. However, at a tumor volume of 1 mm3, which is a typical biopsy sample size, the 633-nm-excited fluorescence signal is only reduced by about 10%. Further simulations revealed that with increasing fiber-tumor distance, the signal drops faster for 405 nm. This reduces the risk of detecting tumor tissue outside the needle's coverage, but diminishes the overlap between optically and mechanically sampled volumes. While 405 nm generally offers a higher sensitivity, 633 nm is more sensitive to distant tumors and considerably superior in case of blood-covered tumor tissue.

  • 35.
    Markwardt, Niklas
    et al.
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Hollnburger, Bastian
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany.
    Stepp, Herbert
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany.
    Zelenkov, Petr
    Burdenko Neurosurgery Institute, Moscow, Russia.
    Rühm, Adrian
    Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Munich, Germany.
    405 nm versus 633 nm for protoporphyrin IX excitation in fluorescence-guided stereotactic biopsy of brain tumors2016Ingår i: Journal of Biophotonics, ISSN 1864-063X, E-ISSN 1864-0648, Vol. 9, nr 9, s. 901-912Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fluorescence diagnosis may be used to improve the safety and reliability of stereotactic brain tumor biopsies using biopsy needles with integrated fiber optics. Based on 5-aminolevulinic-acid-induced protoporphyrin IX (PpIX) fluorescence, vital tumor tissue can be localized in vivo during the excision procedure to reduce the number of necessary samples for a reliable diagnosis. In this study, the practical suitability of two different PpIX excitation wavelengths (405 nm, 633 nm) was investigated on optical phantoms. Violet excitation at 405 nm provides a 50-fold higher sensitivity for the bulk tumor; this factor increases up to 100 with decreasing fluorescent volume as shown by ray tracing simulations. Red excitation at 633 nm, however, is noticeably superior with regard to blood layers obscuring the fluorescence. Experimental results on the signal attenuation through blood layers of well-defined thicknesses could be confirmed by ray tracing simulations. Typical interstitial fiber probe measurements were mimicked on agarose-gel phantoms. Even in direct contact, blood layers of 20-40 µm between probe and tissue must be expected, obscuring 405-nm-excited PpIX fluorescence almost completely, but reducing the 633-nm-excited signal only by 25.5%. Thus, 633 nm seems to be the wavelength of choice for PpIX-assisted detection of high-grade gliomas in stereotactic biopsy. PpIX signal attenuation through clinically relevant blood layers for 405 nm (violet) and 633 nm (red) excitation.

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  • 36.
    Markwardt, Niklas
    et al.
    Klinikum der Univ. München .
    von Berg, Anna
    Klinikum der Univ. München .
    Fiedler, Sebastian
    Klinikum der Univ. München .
    Goetz, Marcus
    MRC Systems GmbH, Germany .
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Polzer, Christoph
    Klinikum der Univ. München .
    Stepp, Herbert
    Klinikum der Univ. München .
    Zelenkov, Petr
    N.N. Burdenko Neurosurgical Institute, Russia .
    Rühm, Adrian
    Klinikum der Univ. München .
    Optical spectroscopy for stereotactic biopsy of brain tumors2015Ingår i: MEDICAL LASER APPLICATIONS AND LASER-TISSUE INTERACTIONS VII, Munich: SPIE - International Society for Optical Engineering, 2015, Vol. 9542, s. 954208-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Stereotactic biopsy procedure is performed to obtain a tissue sample for diagnosis purposes. Currently, a fiber-based mechano-optical device for stereotactic biopsies of brain tumors is developed. Two different fluorophores are employed to improve the safety and reliability of this procedure: The fluorescence of intravenously applied indocyanine green (ICG) facilitates the recognition of blood vessels and thus helps minimize the risk of cerebral hemorrhages. 5- aminolevulinic-acid-induced protoporphyrin IX (PpIX) fluorescence is used to localize vital tumor tissue. ICG fluorescence detection using a 2-fiber probe turned out to be an applicable method to recognize blood vessels about 1.5 mm ahead of the fiber tip during a brain tumor biopsy. Moreover, the suitability of two different PpIX excitation wavelengths regarding practical aspects was investigated: While PpIX excitation in the violet region (at 405 nm) allows for higher sensitivity, red excitation (at 633 nm) is noticeably superior with regard to blood layers obscuring the fluorescence signal. Contact measurements on brain simulating agar phantoms demonstrated that a typical blood coverage of the tumor reduces the PpIX signal to about 75% and nearly 0% for 633 nm and 405 nm excitation, respectively. As a result, 633 nm seems to be the wavelength of choice for PpIX-assisted detection of high-grade gliomas in stereotactic biopsy.

  • 37.
    Rejmstad, Peter
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Haj Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Åneman, Oscar
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Sinnescentrum, Neurokirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Optical monitoring of cerebral microcirculationin neurointensive care2018Ingår i: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 56, nr 7, s. 1201-1210Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuous optical monitoring of local cerebral microcirculation could benefit neurointensive care patients treated for subarachnoid hemorrhage (SAH). The aim of the study was to evaluate laser Doppler flowmetry (LDF) and diffuse reflectance spectroscopy (DRS) for long-term monitoring of brain microcirculation and oxygen saturation (SO2) in the neurointensive care unit (NICU). A fiber optic probe was designed for intraparenchymal use and connected to LDF and DRS for assessment of the local blood flow (perfusion and tissue reflectance (TLI)) and SO2in the brain. The optically monitored parameters were compared with conventional NICU monitors and Xe-CT. The LDF signals were low with median and 25 to 75% interquartiles of perfusion = 70 (59 to 83) a.u. and TLI = 2.0 (1.0 to 2.4) a.u. and showed correlation with the NICU monitors in terms of heart rate. Median and interquartiles of SO2 were 17.4 (15.7 to 19.8) %. The lack of correlation between local perfusion and cerebral perfusion pressure indicated intact cerebral autoregulation. The systems were capable of monitoring both local perfusion and SO2 with stable signals in the NICU over 4 days. Further clinical studies are required to evaluate the optical systems’ potential for assessing the onset of secondary brain injury.

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  • 38.
    Rejmstad, Peter
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Johansson, Johannes D.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    A method for monitoring of oxygen saturation changes in brain tissue using diffuse reflectance spectroscopy2017Ingår i: Journal of Biophotonics, ISSN 1864-063X, E-ISSN 1864-0648, Vol. 10, nr 3, s. 446-455Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuous measurement of local brain oxygen saturation (SO2) can be used to monitor the status of brain trauma patients in the neurocritical care unit. Currently, micro-oxygen-electrodes are considered as the “gold standard” in measuring cerebral oxygen pressure (pO2), which is closely related to SO2 through the oxygen dissociation curve (ODC) of hemoglobin, but with the drawback of slow in response time. The present study suggests estimation of SO2 in brain tissue using diffuse reflectance spectroscopy (DRS) for finding an analytical relation between measured spectra and the SO2 for different blood concentrations. The P3 diffusion approximation is used to generate a set of spectra simulating brain tissue for various levels of blood concentrations in order to estimate SO2. The algorithm is evaluated on optical phantoms mimicking white brain matter (blood volume of 0.5–2%) where pO2 and temperature is controlled and on clinical data collected during brain surgery. The suggested method is capable of estimating the blood fraction and oxygen saturation changes from the spectroscopic signal and the hemoglobin absorption profile.

  • 39.
    Richter, Johan C.O.
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Department of Physics, Lund University.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence Spectroscopy Measurements in Ultrasonic Navigated Resection of Malignant Brain Tumors2011Ingår i: Lasers in Surgery and Medicine, ISSN 0196-8092, E-ISSN 1096-9101, Vol. 43, nr 1, s. 8-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background and Objective: Glioblastoma multiforme is a highly malignant primary brain tumor. It has no border but at best a marginal zone, however, invisible to the surgeon. An optical touch pointer (OTP) enabling differentiation of healthy and tumor tissue by means of fiber-optic fluorescence spectroscopy has been developed. In combination with an ultrasonic navigation system, the OTP may be used for demarcation of resectable tumor tissue. The aim of the study was to evaluate the clinical performance of OTP during surgery of malignant brain tumors. 

    Study Design/Materials and Methods: Nine patients were operated on with the standard surgical procedure, including white light microscopy and navigation. A total of 5 mg/kg bodyweight of 5-amino-levulin acid was orally administrated before surgery. The OTP was calibrated into the ultrasound-based navigation system and measurements were performed in tumor core and along the tumor border. The ratio between the protoporphyrin IX fluorescence at 635 nm and the autofluorescence was used for quantifications of data. Biopsies (n =20), ultrasound images (n = 30), and visual inspection (n =180) were compared to the fluorescence ratio. 

    Results/Conclusion : Healthy and tumor tissue could be identified and differentiated with the OTP(P < 0.001). The fluorescence ratio in average was 0 outside the tumor and low in the gliotic edema zone around the tumor. It increased in the marginal zone and was highest in the solid tumor tissue. In the necrotic tissue, in the center of the tumor, the ratio in average was 0. The OTP can be used in combination with ultrasound-based navigation and may help to determine whether to resect otherwise not identifiable tissue.

  • 40.
    Richter, Johan C.O.
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence Spectroscopy based identification of Glioblastoma multiforme2011Konferensbidrag (Refereegranskat)
  • 41.
    Richter, Johan
    et al.
    Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Haj Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska fakulteten.
    Hallbeck, Martin
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelning för neurobiologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk patologi.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Avdelningen för medicinsk teknik. Linköpings universitet, Tekniska fakulteten.
    Combination of Hand-Held Probe and Microscopy for Fluorescence Guided Surgery in the Brain Tumor Marginal Zone2017Ingår i: Photodiagnosis and Photodynamic Therapy, ISSN 1572-1000, Vol. 18, s. 185-192Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    Visualization of the tumor is crucial for differentiating malignant tissue from healthy brain during surgery, especially in the tumor marginal zone. The aim of the study was to introduce a fluorescence spectroscopy-based hand-held probe (HHF-probe) for tumor identification in combination with the fluorescence guided resection surgical microscope (FGR-microscope), and evaluate them in terms of diagnostic performance and practical aspects of fluorescence detection.

    Material and Methods

    Eighteen operations were performed on 16 patients with suspected high-grade glioma. The HHF-probe and the FGR-microscope were used for detection of protoporphyrin (PpIX) fluorescence induced by 5-aminolevulinic acid (5-ALA) and evaluated against histopathological analysis and visual grading done through the FGR-microscope by the surgeon. A ratio of PpIX fluorescence intensity to the autofluorescence intensity (fluorescence ratio) was used to quantify the spectra detected by the probe.

    Results

    Fluorescence ratio medians (range 0 – 40) measured by the probe were related to the intensity of the fluorescence in the FGR-microscope, categorized as “none” (0.3, n = 131), “weak” (1.6, n = 34) and “strong” (5.4, n = 28). Of 131 “none” points in the FGR-microscope, 88 (67%) exhibited fluorescence with the HHF-probe. For the tumor marginal zone, the area under the receiver operator characteristics (ROC) curve was 0.49 for the FGR-microscope and 0.65 for the HHF-probe.

    Conclusions

    The probe was integrated in the established routine of tumor resection using the FGR-microscope. The HHF-probe was superior to the FGR-microscope in sensitivity; it detected tumor remnants after debulking under the FGR-microscope. The combination of the HHF-probe and the FGR-microscope was beneficial especially in the tumor marginal zone.

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  • 42.
    Richter, Johan
    et al.
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Fluorescence guided brain tumour resection2014Konferensbidrag (Övrigt vetenskapligt)
  • 43.
    Richter, Johan
    et al.
    Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US. Linköpings universitet, Tekniska högskolan.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Linköpings universitet, Tekniska högskolan.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Resection of Glioblastoma multiforme with a fiber-optic fluorescence spectroscopy system and ultrasound based neuronavigation2009Konferensbidrag (Övrigt vetenskapligt)
  • 44.
    Richter, Johan
    et al.
    Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Rekonstruktionscentrum, Neurokirurgiska kliniken US. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Andersson-Engels, Stefan
    Department of Physics, Lund University, Sweden.
    Wårdell, Karin
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Tumor resection with fiber-optic fluorescence spectroscopy system, ultrasound based neuronavigation and peroperative CT-scan2008Ingår i: XVIII Congress of the European Society for Stereotactic and Functional Neurosurgery,2008, 2008Konferensbidrag (Övrigt vetenskapligt)
  • 45.
    Wårdell, Karin
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Haj-Hosseini, Neda
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik.
    Hemm-Ode, Simone
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan. Institute for Medical and Analytical Technologies, University of Applied Sciences and Art Northwestern Switzerland, Basel.
    Comparison between Optical and MRI Trajectories in Stereotactic Neurosurgery2014Ingår i: XIII Mediterranean Conference on Medical and Biological Engineering and Computing 2013 : MEDICON 2013, 25 - 28 September 2013, Seville, Spain / [ed] Laura M. Roa Romero, 2014, s. 49-51Konferensbidrag (Refereegranskat)
    Abstract [en]

    Deep brain stimulation (DBS) is an effective treatment for movement disorders e.g. Parkinson's disease. Thin electrodes are implanted into the deep brain structures by means of stereotactic technique and electrical stimulations are delivered to the brain tissue. Accuracy and safety during the implantation is important for optimal stimulation effect and minimization of bleedings. In addition to microelectrode recording and impedance measurements, intraoperative optical measurements using laser Doppler perfusion monitoring (LDPM) have previously been suggested as guidance tool during stereotactic DBS implantations. In this study we compare optical trajectories, recorded with LDPM ranging from cortex towards the subthalamic nucleus (STN), to the corresponding magnetic resonance imaging (MRI) trajectories. Inversed gray scales from the T2-weighted MRI were used for comparison with the total light intensity (TLI) representing tissue grayness. Both curves followed a general tendency with a deep dip in the vicinity to the left ventricle. MRI trajectories might help in predicting the optical trajectory but further studies including more data and fine tuning of the comparative methodology are required

  • 46.
    Xie, Haiyan
    et al.
    Dept. of Physics, Lund University, Sweden.
    Haj-Hosseini, Neda
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Richter, Johan
    Linköpings universitet, Institutionen för medicinsk teknik. Linköpings universitet, Tekniska högskolan. Östergötlands Läns Landsting, Sinnescentrum, Neurokirurgiska kliniken US.
    Wårdell, Karin
    Linköpings universitet, Institutionen för medicinsk teknik, Biomedicinsk instrumentteknik. Linköpings universitet, Tekniska högskolan.
    Andersson-Engels, Stefan
    Dept. of Physics, Lund University, Sweden.
    Fluorescence spectroscopy for guiding malignant brain tumour resection with Optical Touch Pointer2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Glioblastoma multiforme (GBM), a highly malignant primary brain tumor, is difficult to distinguish from from its surrounding functioning tissue under direct vision in the operating field, since it grows in an infiltrative growth pattern. The main challenge in the surgical treatment of GBM is to fully resect the tumor and avoid neurological impairment. In this paper we extend previous proof-of-principle studies by extending the clinical potential of OTP with the introduction of more sophisticated multivariate analysis schemes. The aim is to distinguish tumor and healthy tissue as well as possible using singular value decomposition (SVD) and cluster analysis methods.

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