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BETA
Warntjes, Marcel, Jan Bertus
Alternative names
Publications (10 of 58) Show all publications
Hagiwara, A., Warntjes, M. J., Hori, M., Andica, C., Nakazawa, M., Kumamaru, K. K., . . . Aoki, S. (2017). SyMRI of the Brain: Rapid Quantification of Relaxation Rates and Proton Density, With Synthetic MRI, Automatic Brain Segmentation, and Myelin Measurement. Investigative Radiology, 52(10), 647-657
Open this publication in new window or tab >>SyMRI of the Brain: Rapid Quantification of Relaxation Rates and Proton Density, With Synthetic MRI, Automatic Brain Segmentation, and Myelin Measurement
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2017 (English)In: Investigative Radiology, ISSN 0020-9996, E-ISSN 1536-0210, Vol. 52, no 10, p. 647-657Article, review/survey (Refereed) Published
Abstract [en]

Conventional magnetic resonance images are usually evaluated using the image signal contrast between tissues and not based on their absolute signal intensities. Quantification of tissue parameters, such as relaxation rates and proton density, would provide an absolute scale; however, these methods have mainly been performed in a research setting. The development of rapid quantification, with scan times in the order of 6 minutes for full head coverage, has provided the prerequisites for clinical use. The aim of this review article was to introduce a specific quantification method and synthesis of contrast-weighted images based on the acquired absolute values, and to present automatic segmentation of brain tissues and measurement of myelin based on the quantitative values, along with application of these techniques to various brain diseases. The entire technique is referred to as "SyMRI" in this review. SyMRI has shown promising results in previous studies when used for multiple sclerosis, brain metastases, Sturge-Weber syndrome, idiopathic normal pressure hydrocephalus, meningitis, and postmortem imaging.

Place, publisher, year, edition, pages
Lippincott Williams & Wilkins, 2017
Keywords
SyMRI, synthetic MRI, quantitative MRI, QRAPMASTER, brain, relaxation rates, proton density, automatic brain segmentation, myelin measurement, multiple sclerosis
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-146343 (URN)10.1097/RLI.0000000000000365 (DOI)000409316200011 ()28257339 (PubMedID)2-s2.0-85014228327 (Scopus ID)
Available from: 2018-04-07 Created: 2018-04-07 Last updated: 2018-04-19Bibliographically approved
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
Zech, W.-D., Hottinger, A.-L., Schwendener, N., Schuster, F., Persson, A., Warntjes, M. J. & Jackowski, C. (2016). Post-mortem 1.5T MR quantification of regular anatomical brain structures. International journal of legal medicine (Print), 130(4), 1071-1080
Open this publication in new window or tab >>Post-mortem 1.5T MR quantification of regular anatomical brain structures
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2016 (English)In: International journal of legal medicine (Print), ISSN 0937-9827, E-ISSN 1437-1596, Vol. 130, no 4, p. 1071-1080Article in journal (Refereed) Published
Abstract [en]

Recently, post-mortem MR quantification has been introduced to the field of post-mortem magnetic resonance imaging. By usage of a particular MR quantification sequence, T1 and T2 relaxation times and proton density (PD) of tissues and organs can be quantified simultaneously. The aim of the present basic research study was to assess the quantitative T1, T2, and PD values of regular anatomical brain structures for a 1.5T application and to correlate the assessed values with corpse temperatures. In a prospective study, 30 forensic cases were MR-scanned with a quantification sequence prior to autopsy. Body temperature was assessed during MR scans. In synthetically calculated T1, T2, and PD-weighted images, quantitative T1, T2 (both in ms) and PD (in %) values of anatomical structures of cerebrum (Group 1: frontal gray matter, frontal white matter, thalamus, internal capsule, caudate nucleus, putamen, and globus pallidus) and brainstem/cerebellum (Group 2: cerebral crus, substantia nigra, red nucleus, pons, cerebellar hemisphere, and superior cerebellar peduncle) were assessed. The investigated brain structures of cerebrum and brainstem/cerebellum could be characterized and differentiated based on a combination of their quantitative T1, T2, and PD values. MANOVA testing verified significant differences between the investigated anatomical brain structures among each other in Group 1 and Group 2 based on their quantitative values. Temperature dependence was observed mainly for T1 values, which were slightly increasing with rising temperature in the investigated brain structures in both groups. The results provide a base for future computer-aided diagnosis of brain pathologies and lesions in post-mortem magnetic resonance imaging.

Place, publisher, year, edition, pages
Springer, 2016
Keywords
Brain, MR quantification, Post-mortem magnetic resonance imaging (PMMR), Forensic, Neuroimaging
National Category
Pharmacology and Toxicology
Identifiers
urn:nbn:se:liu:diva-130269 (URN)10.1007/s00414-016-1318-3 (DOI)000378817900026 ()26872469 (PubMedID)
Available from: 2016-08-01 Created: 2016-07-28 Last updated: 2018-01-10Bibliographically approved
Virhammar, J., Warntjes, M. J., Laurell, K. & Larsson, E.-M. -. (2016). Quantitative MRI for Rapid and User-Independent Monitoring of Intracranial CSF Volume in Hydrocephalus. American Journal of Neuroradiology, 37(5), 797-801
Open this publication in new window or tab >>Quantitative MRI for Rapid and User-Independent Monitoring of Intracranial CSF Volume in Hydrocephalus
2016 (English)In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 37, no 5, p. 797-801Article in journal (Refereed) Published
Abstract [en]

BACKGROUND AND PURPOSE: Quantitative MR imaging allows segmentation of different tissue types and automatic calculation of intracranial volume, CSF volume, and brain parenchymal fraction. Brain parenchymal fraction is calculated as (intracranial volume - CSF volume) / intracranial volume. The purpose of this study was to evaluate whether the automatic calculation of intracranial CSF volume or brain parenchymal fraction could be used as an objective method to monitor volume changes in the ventricles. MATERIALS AND METHODS: A lumbar puncture with drainage of 40 mL of CSF was performed in 23 patients under evaluation for idiopathic normal pressure hydrocephalus. Quantitative MR imaging was performed twice within 1 hour before the lumbar puncture and was repeated 30 minutes, 4 hours, and 24 hours afterward. For each time point, the volume of the lateral ventricles was manually segmented and total intracranial CSF volume and brain parenchymal fraction were automatically calculated by using Synthetic MR postprocessing. RESULTS: At 30 minutes after the lumbar puncture, the volume of the lateral ventricles decreased by 5.6 +/- 1.9 mL (P < .0001) and the total intracranial CSF volume decreased by 11.3 +/- 5.6 mL (P < .001), while brain parenchymal fraction increased by 0.78% +/- 0.41% (P < .001). Differences were significant for manual segmentation and brain parenchymal fraction even at 4 hours and 24 hours after the lumbar tap. There was a significant association using a linear mixed model between change in manually segmented ventricular volume and change in brain parenchymal fraction and total CSF volume, (P < .0001). CONCLUSIONS: Brain parenchymal fraction is provided rapidly and fully automatically with Synthetic MRI and can be used to monitor ventricular volume changes. The method may be useful for objective clinical monitoring of hydrocephalus.

Place, publisher, year, edition, pages
AMER SOC NEURORADIOLOGY, 2016
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-128939 (URN)10.3174/ajnr.A4627 (DOI)000375820300004 ()26705322 (PubMedID)
Note

Funding Agencies|Independent Swedish Foundation Selanders Stiftelse grant; SyntheticMR

Available from: 2016-06-09 Created: 2016-06-07 Last updated: 2017-11-30
Zech, W.-D., Schwendener, N., Persson, A., Warntjes, M. J. & Jackowski, C. (2015). Postmortem MR quantification of the heart for characterization and differentiation of ischaemic myocardial lesions. European Radiology, 25(7), 2067-2073
Open this publication in new window or tab >>Postmortem MR quantification of the heart for characterization and differentiation of ischaemic myocardial lesions
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2015 (English)In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 25, no 7, p. 2067-2073Article in journal (Refereed) Published
Abstract [en]

Recently, an MRI quantification sequence has been developed which can be used to acquire T1- and T2-relaxation times as well as proton density (PD) values. Those three quantitative values can be used to describe soft tissue in an objective manner. The purpose of this study was to investigate the applicability of quantitative cardiac MRI for characterization and differentiation of ischaemic myocardial lesions of different age. Fifty post-mortem short axis cardiac 3 T MR examinations have been quantified using a quantification sequence. Myocardial lesions were identified according to histology and appearance in MRI images. Ischaemic lesions were assessed for mean T1-, T2- and proton density values. Quantitative values were plotted in a 3D-coordinate system to investigate the clustering of ischaemic myocardial lesions. A total of 16 myocardial lesions detected in MRI images were histologically characterized as acute lesions (n = 8) with perifocal oedema (n = 8), subacute lesions (n = 6) and chronic lesions (n = 2). In a 3D plot comprising the combined quantitative values of T1, T2 and PD, the clusters of all investigated lesions could be well differentiated from each other. Post-mortem quantitative cardiac MRI is feasible for characterization and discrimination of different age stages of myocardial infarction. aEuro cent MR quantification is feasible for characterization of different stages of myocardial infarction. aEuro cent The results provide the base for computer-aided MRI cardiac infarction diagnosis. aEuro cent Diagnostic criteria may also be applied for living patients.

Place, publisher, year, edition, pages
Springer Verlag (Germany), 2015
Keywords
Post-mortem quantitative magnetic resonance imaging; Myocardial infarction; Ischaemia; Left ventricular; Post-mortem cardiac imaging
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-119784 (URN)10.1007/s00330-014-3582-2 (DOI)000355755300026 ()25591749 (PubMedID)
Available from: 2015-06-26 Created: 2015-06-26 Last updated: 2017-12-04Bibliographically approved
Zech, W.-D., Schwendener, N., Persson, A., Warntjes, M. J., Riva, F., Schuster, F. & Jackowski, C. (2015). Postmortem quantitative 1.5-T MRI for the differentiation and characterization of serous fluids, blood, CSF, and putrefied CSF. International journal of legal medicine (Print), 129(5), 1127-1136
Open this publication in new window or tab >>Postmortem quantitative 1.5-T MRI for the differentiation and characterization of serous fluids, blood, CSF, and putrefied CSF
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2015 (English)In: International journal of legal medicine (Print), ISSN 0937-9827, E-ISSN 1437-1596, Vol. 129, no 5, p. 1127-1136Article in journal (Refereed) Published
Abstract [en]

The purpose of the present study was to investigate whether serous fluids, blood, cerebrospinal fluid (CSF), and putrefied CSF can be characterized and differentiated in synthetically calculated magnetic resonance (MR) images based on their quantitative T (1), T (2), and proton density (PD) values. Images from 55 postmortem short axis cardiac and 31 axial brain 1.5-T MR examinations were quantified using a quantification sequence. Serous fluids, fluid blood, sedimented blood, blood clots, CSF, and putrefied CSF were analyzed for their mean T (1), T (2), and PD values. Body core temperature was measured during the MRI scans. The fluid-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. In a 3D plot as well as in statistical analysis, the quantitative T (1), T (2) and PD values of serous fluids, fluid blood, sedimented blood, blood clots, CSF, and putrefied CSF could be well differentiated from each other. The quantitative T (1) and T (2) values were temperature-dependent. Correction of quantitative values to a temperature of 37 A degrees C resulted in significantly better discrimination between all investigated fluid mediums. We conclude that postmortem 1.5-T MR quantification is feasible to discriminate between blood, serous fluids, CSF, and putrefied CSF. This finding provides a basis for the computer-aided diagnosis and detection of fluids and hemorrhages.

Place, publisher, year, edition, pages
Springer, 2015
Keywords
Postmortem quantitative MRI; Forensic imaging; Serous fluids; Blood; Putrefaction
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-121430 (URN)10.1007/s00414-015-1218-y (DOI)000360315900029 ()26162597 (PubMedID)
Available from: 2015-09-18 Created: 2015-09-18 Last updated: 2017-12-04Bibliographically approved
Zech, W.-D., Schwendener, N., Persson, A., Bertus Warntjes, M. J. & Jackowski, C. (2015). Temperature dependence of postmortem MR quantification for soft tissue discrimination. European Radiology, 25(8), 2381-2389
Open this publication in new window or tab >>Temperature dependence of postmortem MR quantification for soft tissue discrimination
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2015 (English)In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Temperature dependence of postmortem MR quantification for soft tissue discrimination, Vol. 25, no 8, p. 2381-2389Article in journal (Refereed) Published
Abstract [en]

Objectives To investigate and correct the temperature dependence of postmortem MR quantification used for soft tissue characterization and differentiation in thoraco-abdominal organs. Material and methods Thirty-five postmortem short axis cardiac 3-T MR examinations were quantified using a quantification sequence. Liver, spleen, left ventricular myocardium, pectoralis muscle and subcutaneous fat were analysed in cardiac short axis images to obtain mean T1, T2 and PD tissue values. The core body temperature was measured using a rectally inserted thermometer. The tissue-specific quantitative values were related to the body core temperature. Equations to correct for temperature differences were generated. Results In a 3D plot comprising the combined data of T1, T2 and PD, different organs/tissues could be well differentiated from each other. The quantitative values were influenced by the temperature. T1 in particular exhibited strong temperature dependence. The correction of quantitative values to a temperature of 37 °C resulted in better tissue discrimination. Conclusion Postmortem MR quantification is feasible for soft tissue discrimination and characterization of thoracoabdominal organs. This provides a base for computer-aided diagnosis and detection of tissue lesions. The temperature dependence of the T1 values challenges postmortem MR quantification. Equations to correct for the temperature dependence are provided.

Keywords
Postmortem magnetic resonance imaging; Quantitative MRI; MRI temperature dependence; Soft tissue; Thoraco-abdominal organs
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-113888 (URN)10.1007/s00330-015-3588-4 (DOI)000357660100023 ()25636417 (PubMedID)
Available from: 2015-02-03 Created: 2015-02-03 Last updated: 2017-12-05
Warntjes, M. J., Tisell, A., Landtblom, A.-M. & Lundberg, P. (2014). Effects of Gadolinium Contrast Agent Administration on Automatic Brain Tissue Classification of Patients with Multiple Sclerosis. American Journal of Neuroradiology, 35(7), 1330-1336
Open this publication in new window or tab >>Effects of Gadolinium Contrast Agent Administration on Automatic Brain Tissue Classification of Patients with Multiple Sclerosis
2014 (English)In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 35, no 7, p. 1330-1336Article in journal (Refereed) Published
Abstract [en]

BACKGROUND AND PURPOSE:

The administration of gadolinium contrast agent is a common part of MR imaging examinations in patients with MS. The presence of gadolinium may affect the outcome of automated tissue classification. The purpose of this study was to investigate the effects of the presence of gadolinium on the automatic segmentation in patients with MS by using the synthetic tissue-mapping method.

MATERIALS AND METHODS:

A cohort of 20 patients with clinically definite multiple sclerosis were recruited, and the T1 and T2 relaxation times and proton density were simultaneously quantified before and after the administration of gadolinium. Synthetic tissue-mapping was used to measure white matter, gray matter, CSF, brain parenchymal, and intracranial volumes. For comparison, 20 matched controls were measured twice, without gadolinium.

RESULTS:

No differences were observed for the control group between the 2 measurements. For the MS group, significant changes were observed pre- and post-gadolinium in intracranial volume (-13 mL, P < .005) and cerebrospinal fluid volume (-16 mL, P < .005) and the remaining, unclassified non-WM/GM/CSF tissue volume within the intracranial volume (+8 mL, P < .05). The changes in the patient group were much smaller than the differences, compared with the controls, which were -129 mL for WM volume, -22 mL for GM volume, +91 mL for CSF volume, 24 mL for the remaining, unclassified non-WM/GM/CSF tissue volume within the intracranial volume, and -126 mL for brain parenchymal volume. No significant differences were observed for linear regression values against age and Expanded Disability Status Scale.

CONCLUSIONS:

The administration of gadolinium contrast agent had a significant effect on automatic brain-tissue classification in patients with MS by using synthetic tissue-mapping. The observed differences, however, were much smaller than the group differences between MS and controls.

Place, publisher, year, edition, pages
American Society of Neuroradiology, 2014
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-109381 (URN)10.3174/ajnr.A3890 (DOI)000339138200015 ()24699093 (PubMedID)
Available from: 2014-08-15 Created: 2014-08-15 Last updated: 2017-12-05Bibliographically approved
Engström, M., Bertus Warntjes, M. J., Tisell, A., Landtblom, A.-M. & Lundberg, P. (2014). Multi-Parametric Representation of Voxel-Based Quantitative Magnetic Resonance Imaging. PLoS ONE, 9(11), e111688
Open this publication in new window or tab >>Multi-Parametric Representation of Voxel-Based Quantitative Magnetic Resonance Imaging
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2014 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 11, p. e111688-Article in journal (Refereed) Published
Abstract [en]

The aim of the study was to explore the possibilities of multi-parametric representations of voxel-wise quantitative MRI data to objectively discriminate pathological cerebral tissue in patients with brain disorders. For this purpose, we recruited 19 patients with Multiple Sclerosis (MS) as benchmark samples and 19 age and gender matched healthy subjects as a reference group. The subjects were examined using quantitative Magnetic Resonance Imaging (MRI) measuring the tissue structure parameters: relaxation rates, R-1 and R-2, and proton density. The resulting parameter images were normalized to a standard template. Tissue structure in MS patients was assessed by voxel-wise comparisons with the reference group and with correlation to a clinical measure, the Expanded Disability Status Scale (EDSS). The results were visualized by conventional geometric representations and also by multi-parametric representations. Data showed that MS patients had lower R-1 and R-2, and higher proton density in periventricular white matter and in wide-spread areas encompassing central and sub-cortical white matter structures. MS-related tissue abnormality was highlighted in posterior white matter whereas EDSS correlation appeared especially in the frontal cortex. The multi-parameter representation highlighted disease-specific features. In conclusion, the proposed method has the potential to visualize both high-probability focal anomalies and diffuse tissue changes. Results from voxel-based statistical analysis, as exemplified in the present work, may guide radiologists where in the image to inspect for signs of disease. Future clinical studies must validate the usability of the method in clinical practice.

Place, publisher, year, edition, pages
Public Library of Science, 2014
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-114027 (URN)10.1371/journal.pone.0111688 (DOI)000347709300018 ()25393722 (PubMedID)
Note

Funding Agencies|National Research Council [VR/NT 2008-3368]; Linkoping University; County Council of Ostergotland

Available from: 2015-02-05 Created: 2015-02-05 Last updated: 2017-12-05
Engström, M., Jan Bertus Warntje, M., Tisell, A., Landtblom, A.-M. & Lundberg, P. (2014). Multi-Parametric Representation of Voxel-Based Quantitative Magnetic Resonance Imaging. In: : . Paper presented at The International Society for Magnetic Resonance in Medicine (ISMRM) 2014, Milan, Italy (pp. e111688). , 9
Open this publication in new window or tab >>Multi-Parametric Representation of Voxel-Based Quantitative Magnetic Resonance Imaging
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2014 (English)Conference paper, Poster (with or without abstract) (Other academic)
Abstract [en]

The aim of the study was to explore the possibilities of multi-parametric representations of voxel-wise quantitative MRI data to objectively discriminate pathological cerebral tissue in patients with brain disorders. For this purpose, we recruited 19 patients with Multiple Sclerosis (MS) as benchmark samples and 19 age and gender matched healthy subjects as a reference group. The subjects were examined using quantitative Magnetic Resonance Imaging (MRI) measuring the tissue structure parameters: relaxation rates, R and R, and proton density. The resulting parameter images were normalized to a standard template. Tissue structure in MS patients was assessed by voxel-wise comparisons with the reference group and with correlation to a clinical measure, the Expanded Disability Status Scale (EDSS). The results were visualized by conventional geometric representations and also by multi-parametric representations. Data showed that MS patients had lower R and R, and higher proton density in periventricular white matter and in wide-spread areas encompassing central and sub-cortical white matter structures. MS-related tissue abnormality was highlighted in posterior white matter whereas EDSS correlation appeared especially in the frontal cortex. The multi-parameter representation highlighted disease-specific features. In conclusion, the proposed method has the potential to visualize both high-probability focal anomalies and diffuse tissue changes. Results from voxel-based statistical analysis, as exemplified in the present work, may guide radiologists where in the image to inspect for signs of disease. Future clinical studies must validate the usability of the method in clinical practice.

National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-114360 (URN)10.1371/journal.pone.0111688 (DOI)25393722 (PubMedID)
Conference
The International Society for Magnetic Resonance in Medicine (ISMRM) 2014, Milan, Italy
Available from: 2015-02-19 Created: 2015-02-19 Last updated: 2018-02-22
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