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- Järnum, Hanna, et al.
(författare)
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Longitudinal MRI study of cortical thickness, perfusion, and metabolite levels in major depressive disorder
- 2011
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Ingår i: Acta Psychiatrica Scandinavica. - : Wiley. - 0001-690X .- 1600-0447. ; 124:6, s. 435-446
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To determine whether patients with major depressive disorder (MDD) display morphologic, functional, and metabolic brain abnormalities in limbic-cortical regions at a baseline magnetic resonance (MR) scan and whether these changes are normalized in MDD patients in remission at a follow-up scan. Method: A longitudinal 3.0-Tesla (T) magnetic resonance imaging (MRI) study was carried out with cortical thickness measurements with a surface-based approach, perfusion measurements with three-dimensional (3D) pseudo-continuous arterial spin labeling (pCASL), and spectroscopy (1H-MRS) measurements in the anterior cingulate cortex (ACC) with water as an internal reference adjusted for cerebrospinal fluid content. We examined 23 MDD patients and 26 healthy controls. MDD patients underwent a baseline MRI at inclusion and were invited to a follow-up scan when they were in remission or after a 6-month follow-up period. Results: Major findings were a significantly thinner posterior cingulate cortex in non-remitters than in remitters, a significant decrease in perfusion in the frontal lobes and the ACC in non-remitters compared with healthy controls at baseline and significantly reduced N-acetylaspartate, myo-inositol, and glutamate levels in MDD patients compared with healthy controls at baseline. Conclusion: Using novel MRI techniques, we have found abnormalities in cerebral regions related to cortical-limbic pathways in MDD patients.
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2. |
- Järnum, Hanna, et al.
(författare)
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Perfusion MRI of brain tumours : a comparative study of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast imaging
- 2010
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Ingår i: Neuroradiology. - : Springer Science and Business Media LLC. - 0028-3940 .- 1432-1920. ; 52:4, s. 307-317
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: The purpose of this study was to compare the non-invasive 3D pseudo-continuous arterial spin labelling (PC ASL) technique with the clinically established dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI) for evaluation of brain tumours. METHODS: A prospective study of 28 patients with contrast-enhancing brain tumours was performed at 3 T using DSC-MRI and PC ASL with whole-brain coverage. The visual qualitative evaluation of signal enhancement in tumour was scored from 0 to 3 (0 = no signal enhancement compared with white matter, 3 = pronounced signal enhancement with equal or higher signal intensity than in grey matter/basal ganglia). The extent of susceptibility artefacts in the tumour was scored from 0 to 2 (0 = no susceptibility artefacts and 2 = extensive susceptibility artefacts (maximum diameter > 2 cm)). A quantitative analysis was performed with normalised tumour blood flow values (ASL nTBF, DSC nTBF): mean value for region of interest (ROI) in an area with maximum signal enhancement/the mean value for ROIs in cerebellum. RESULTS: There was no difference in total visual score for signal enhancement between PC ASL and DSC relative cerebral blood flow (p = 0.12). ASL had a lower susceptibility-artefact score than DSC-MRI (p = 0.03). There was good correlation between DSC nTBF and ASL nTBF values with a correlation coefficient of 0.82. CONCLUSION: PC ASL is an alternative to DSC-MRI for the evaluation of perfusion in brain tumours. The method has fewer susceptibility artefacts than DSC-MRI and can be used in patients with renal failure because no contrast injection is needed.
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- Nordlund, David, et al.
(författare)
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Extent of myocardium at risk for left anterior descending artery, right coronary artery, and left circumflex artery occlusion depicted by contrast-enhanced steady state free precession and T2-weighted short tau inversion recovery magnetic resonance imaging
- 2016
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Ingår i: Circulation Cardiovascular Imaging. - 1941-9651. ; 9:7
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Tidskriftsartikel (refereegranskat)abstract
- Background - Contrast-enhanced steady state free precession (CE-SSFP) and T2-weighted short tau inversion recovery (T2-STIR) have been clinically validated to estimate myocardium at risk (MaR) by cardiovascular magnetic resonance while using myocardial perfusion single-photon emission computed tomography as reference standard. Myocardial perfusion single-photon emission computed tomography has been used to describe the coronary perfusion territories during myocardial ischemia. Compared with myocardial perfusion single-photon emission computed tomography, cardiovascular magnetic resonance offers superior image quality and practical advantages. Therefore, the aim was to describe the main coronary perfusion territories using CE-SSFP and T2-STIR cardiovascular magnetic resonance data in patients after acute ST-segment-elevation myocardial infarction. Methods and Results - CE-SSFP and T2-STIR data from 2 recent multicenter trials, CHILL-MI and MITOCARE (n=215), were used to assess MaR. Angiography was used to determine culprit vessel. Of 215 patients, 39% had left anterior descending artery occlusion, 49% had right coronary artery occlusion, and 12% had left circumflex artery occlusion. Mean extent of MaR using CE-SSFP was 44±10% for left anterior descending artery, 31±7% for right coronary artery, and 30±9% for left circumflex artery. Using T2-STIR, MaR was 44±9% for left anterior descending artery, 30±8% for right coronary artery, and 30±12% for left circumflex artery. MaR was visualized in polar plots, and expected overlap was found between right coronary artery and left circumflex artery. Detailed regional data are presented for use in software algorithms as a priori information on the extent of MaR. Conclusions - For the first time, cardiovascular magnetic resonance has been used to show the main coronary perfusion territories using CE-SSFP and T2-STIR. The good agreement between CE-SSFP and T2-STIR from this study and myocardial perfusion single-photon emission computed tomography from previous studies indicates that these 3 methods depict MaR accurately in individual patients and at a group level. Clinical Trial Registration - URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01379261 and NCT01374321.
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