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Canale S, Rodrigo S, Tourdias T, Mellerio C, Perrin M, Souillard R, Oppenheim C, Meder JF. [Grading of adults primitive glial neoplasms using arterial spin-labeled perfusion MR imaging]. J Neuroradiol 2011; 38:207-13. [PMID: 21353707 DOI: 10.1016/j.neurad.2010.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2010] [Revised: 12/05/2010] [Accepted: 12/12/2010] [Indexed: 11/29/2022]
Abstract
PURPOSE We investigated the relationship between tumor blood-flow measurement based on perfusion-imaging by arterial spin-labeling (ASL) and histopathologic findings in adults' primitive glial tumours. PATIENTS AND METHODS Thus, 40 primitive brain tumors (8 low-grade and 32 high-grade gliomas according to the Sainte-Anne classification) were imaged using pulsed (n=19) or continuous (n=21) ASL. Relative cerebral blood flow (rCBF=tumoral blood flow/normal cerebral blood flow) between high- and low-grade gliomas were compared. RESULTS Using pulsed ASL, differences in mean rCBF were observed in high- and low-grade gliomas although no significant (respectively 1.95 and 1.5). Using continuous ASL, mean rCBF were significantly higher for high-grade than for low-grade gliomas (P<0.05). High-grade gliomas could be discriminated using a CBF threshold of 1.18, with a sensitivity of 88%, specificity of 60%, predictive positive value of 88%, and predictive negative value of 60%. CONCLUSION ASL-based perfusion provides a quantitative, non-invasive alternative to dynamic susceptibility contrast perfusion MR methods for evaluating CBF. ASL is a suitable method for gliomas initial staging and could be useful to identify intermediate tumoral evolution.
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Oppenheim C, Touzé E. MRI IN CAROTID PLAQUE. Artery Res 2011. [DOI: 10.1016/j.artres.2011.10.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
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53
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Urbanski M, Thiebaut de Schotten M, Rodrigo S, Oppenheim C, Touzé E, Méder JF, Moreau K, Loeper-Jeny C, Dubois B, Bartolomeo P. DTI-MR tractography of white matter damage in stroke patients with neglect. Exp Brain Res 2010; 208:491-505. [PMID: 21113581 DOI: 10.1007/s00221-010-2496-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
Abstract
Left visual neglect is a dramatic neurological condition that impairs awareness of left-sided events. Neglect has been classically reported after strokes in the territory of the right middle cerebral artery. However, the precise lesional correlates of neglect within this territory remain discussed. Recent evidence strongly suggests an implication of dysfunction of large-scale perisylvian networks in chronic neglect, but the quantitative relationships between neglect signs and damage to white matter (WM) tracts have never been explored. In this prospective study, we used diffusion tensor imaging (DTI) tractography in twelve patients with a vascular stroke in the right hemisphere. Six of these patients showed signs of neglect. Nonparametric voxel-based comparisons between neglect and controls on fractional anisotropy maps revealed clusters in the perisylvian WM and in the external capsule. Individual DTI tractography identified specific disconnections of the fronto-parietal and fronto-occipital pathways in the neglect group. Voxel-based correlation statistics highlighted correlations between patients' performance on two visual search tasks and damage to WM clusters. These clusters were located in the anterior limb of the internal capsule and in the WM underlying the inferior frontal gyrus, along the trajectory of the anterior segment of the arcuate fasciculus (asAF). These results indicate that chronic visual neglect can result from, and correlate with, damage to fronto-parietal connections in the right hemisphere, within large-scale cortical networks important for orienting of spatial attention, arousal and spatial working memory.
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Naggara O, Louillet F, Touzé E, Roy D, Leclerc X, Mas JL, Pruvo JP, Meder JF, Oppenheim C. Added value of high-resolution MR imaging in the diagnosis of vertebral artery dissection. AJNR Am J Neuroradiol 2010; 31:1707-12. [PMID: 20595374 DOI: 10.3174/ajnr.a2165] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The optimal imaging method for the diagnosis of VAD remains undefined. Our aim was to evaluate the added value of HR-MR imaging for the diagnosis of VAD. MATERIALS AND METHODS We retrospectively extracted 35 consecutive patients suspected of having acute VAD who had the following: 1) a focal lumen abnormality of the VA on CE-MRA, 2) HR-MR imaging during the initial hospital stay, and 3) clinical and imaging follow-up within 6 months. Two neurologists classified patients as either VAD (group A) or non-VAD (group B) by reviewing all the available data at hospital discharge, except HR-MR imaging data. On HR-MR imaging, 2 radiologists searched for signs of acute VAD. The 2 classifications were compared. In case of discordance, CE-MRA follow-up and axial fat-suppressed T1WI, used to obtain supportive evidence for or against VAD, were considered as the standard of reference. RESULTS In 4/18 patients in group A, HR-MR imaging did not demonstrate any signs of acute VAD and perivertebral signal-intensity changes were attributed to venous plexus, with an unchanged lumen on follow-up. In 4/17 patients in group B, HR-MRI demonstrated a mural hematoma, with lumen normalization on follow-up CE-MRA. CONCLUSIONS Our results encourage the use of HR-MR imaging as a second-line diagnostic tool in the event of suspicion of acute VAD and doubtful findings on standard imaging.
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Naggara O, Létourneau-Guillon L, Mellerio C, Belair M, Pruvo JP, Leclerc X, Meder JF, Oppenheim C. [Diffusion-weighted MR imaging of the brain]. JOURNAL DE RADIOLOGIE 2010; 91:329-49; quiz 350-1. [PMID: 20508569 DOI: 10.1016/s0221-0363(10)70050-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Imaging of water diffusion or diffusion-weighted MR imaging provides physiological information about brain diseases that cannot be obtained from conventional sequences. This technique is very sensitive for the detection of cerebral ischemia from arterial origin and can distinguish cerebral ischemia from other non-vascular brain pathologies in patients presenting with abrupt onset of focal neurological deficit. Diffusion-weighted imaging is used for the evaluation of non-vascular diseases as well. Combined with conventional sequences, it is helpful to differentiate brain abscesses from necrotic tumors. Quantitative diffusion-weighted imaging provides additional information in the characterization of tumors or inflammatory, degenerative and metabolic lesions. Finally, diffusion-weighted imaging data also has prognostic value.
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Naggara O, Oppenheim C, Louillet F, Touzé E, Mas JL, Leclerc X, Meder JF. Traumatic intracranial dissection: Mural hematoma on high-resolution MRI. J Neuroradiol 2010; 37:136-7. [DOI: 10.1016/j.neurad.2009.07.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 07/30/2009] [Indexed: 11/29/2022]
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57
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Oppenheim C. [The broadening applications of diffusion-weighted imaging]. JOURNAL DE RADIOLOGIE 2010; 91:328. [PMID: 20508568 DOI: 10.1016/s0221-0363(10)70049-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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58
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Gonçalves AMG, Page P, Domigo V, Méder JF, Oppenheim C. Abrupt regression of a meningioma after discontinuation of cyproterone treatment. AJNR Am J Neuroradiol 2010; 31:1504-5. [PMID: 20053802 DOI: 10.3174/ajnr.a1978] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The multiplicity of meningiomas or abrupt lesion growth in patients treated with cyproterone acetate suggests that this progestative treatment may promote lesion growth. We report the rapid regression of an incidental meningioma after discontinuation of a 10-year cyproterone acetate treatment. This unique observation suggests that conservative management of meningiomas may be the best option among users of high doses of cyproterone acetate, given that spontaneous regression may occur after hormonal treatment discontinuation.
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Brami F, Domigo V, Godon-Hardy S, Trystram D, Oppenheim C, Méder JF. [Clinical and imaging features of diffuse cerebral vasoconstriction]. JOURNAL DE RADIOLOGIE 2009; 90:1731-1736. [PMID: 19953061 DOI: 10.1016/s0221-0363(09)73272-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
PURPOSE To report clinical and imaging features of diffuse cerebral vasoconstriction and to discuss the role of non-invasive imaging modalities for the diagnosis and the follow-up. PATIENTS AND METHODS Retrospective study including 13 consecutive patients with a diffuse cerebral vasoconstriction. Evaluation of the sensitivity of Doppler US and magnetic resonance angiography for the diagnosis. RESULTS The diagnosis is based on the association of a thunderclap headache, declenching factors found in 50% of cases and of stenosis involving middle and small cerebra arteries. In some cases cerebral hemorrhage may be present. DISCUSSION Diffuse cerebral vasoconstriction is a rare cause of thunder clap headhache, which needs to exclude other causes such as subarchnoid hemorrhage from aneurysm rupture. Non contrast CT of the head, frequently normal, may be falsely reassuring. It is therefore necessary to further assess the cerebral arteries to exclude an aneurysm but also to detect the presence of stenoses that would suggest the diagnosis. Non-invasive imaging modalities (MRA and Doppler US) are favored for detection and follow-up of proximal lesions.
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Beaussier H, Naggara O, Calvet D, Joannides R, Guegan-Massardier E, Gerardin E, Iacob M, Laloux B, Bozec E, Bellien J, Masson I, Oppenheim C, Boutouyrie P, Laurent S. I017 Contrainte de courbure et structure des plaques carotidiennes : analyse par echotracking multibarrettes et IRM. Arch Cardiovasc Dis 2009. [DOI: 10.1016/s1875-2136(09)72351-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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61
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Naggara O, Meary E, Marsico R, Oppenheim C, Meder JF, Nataf F. Optochiasmal apoplexy due to a cavernoma. J Neuroradiol 2008; 36:111-2. [PMID: 18829113 DOI: 10.1016/j.neurad.2008.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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62
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Brami-Zylberberg F, Charbonneau F, Naggara O, Rodrigo S, Oppenheim C, Pruvo JP, Meder JF. [Imaging of acute confusional state]. JOURNAL DE RADIOLOGIE 2008; 89:843-851. [PMID: 18772746 DOI: 10.1016/s0221-0363(08)73872-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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63
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Piana G, Naggara O, Oppenheim C, Rodrigo S, Meder JF, Marsico R, Page P. Epidermoid-cyst of the conus medullaris: usefulness of DWI. J Neuroradiol 2008; 35:304-5. [PMID: 18466975 DOI: 10.1016/j.neurad.2008.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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64
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Rodrigo S, Oppenheim C, Jissendi P, Soto-Ares G, Pruvo JP, Meder JF. Nouvelles techniques d’IRM morphologique et fonctionnelle. Neurochirurgie 2008; 54:197-207. [DOI: 10.1016/j.neuchi.2008.02.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 02/23/2008] [Indexed: 11/27/2022]
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65
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Urbanski M, Thiebaut de Schotten M, Rodrigo S, Catani M, Oppenheim C, Touzé E, Chokron S, Méder JF, Lévy R, Dubois B, Bartolomeo P. Brain networks of spatial awareness: evidence from diffusion tensor imaging tractography. J Neurol Neurosurg Psychiatry 2008; 79:598-601. [PMID: 17991702 PMCID: PMC2386830 DOI: 10.1136/jnnp.2007.126276] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Left unilateral neglect, a dramatic condition which impairs awareness of left-sided events, has been classically reported after right hemisphere cortical lesions involving the inferior parietal region. More recently, the involvement of long range white matter tracts has been highlighted, consistent with the idea that awareness of events occurring in space depends on the coordinated activity of anatomically distributed brain regions. Damage to the superior longitudinal fasciculus (SLF), linking parietal to frontal cortical regions, or to the inferior longitudinal fasciculus (ILF), connecting occipital and temporal lobes, has been described in neglect patients. In this study, four right-handed patients with right hemisphere strokes underwent a high definition anatomical MRI with diffusion tensor imaging (DTI) sequences and a pencil and paper neglect battery of tests. We used DTI tractography to visualise the SLF, ILF and the inferior fronto-occipital fasciculus (IFOF), a pathway running the depth of the temporal lobe, not hitherto associated with neglect. Two patients with cortical involvement of the inferior parietal and superior temporal regions, but intact and symmetrical fasciculi, showed no signs of neglect. The other two patients with signs of left neglect had superficial damage to the inferior parietal cortex and white matter damage involving the IFOF. These findings suggest that superficial damage to the inferior parietal cortex per se may not be sufficient to produce visual neglect. In some cases, a lesion to the direct connections between ventral occipital and frontal regions (ie, IFOF) may contribute to the manifestation of neglect by impairing the top down modulation of visual areas from the frontal cortex.
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66
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Rodrigo S, Oppenheim C, Leclerc X, Soto-Ares G, Pruvo JP, Meder JF. [Structural MRI in adult partial epilepsy]. Neurochirurgie 2008; 54:191-6. [PMID: 18440567 DOI: 10.1016/j.neuchi.2008.02.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 02/25/2008] [Indexed: 11/27/2022]
Abstract
Magnetic resonance imaging (MRI) is the prominent imaging modality in the field of epilepsy. MRI plays a major role in describing and recognizing the malformations of cortical development and hippocampal sclerosis and has improved epilepsy patient care. MRI is also accurate in detecting the other major epilepsy etiologies (vascular malformations and cicatricial lesions). Presurgical MRI is relevant since it provides a high-resolution study of the brain.
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67
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Iosif C, Oppenheim C, Trystram D, Domigo V, Méder JF. MR imaging-based decision in thrombolytic therapy for stroke on awakening: report of 2 cases. AJNR Am J Neuroradiol 2008; 29:1314-6. [PMID: 18388211 DOI: 10.3174/ajnr.a1069] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Patients with stroke on awakening are denied the potential benefit of thrombolysis on the grounds that the onset time is unknown. Relying on clinical and MR imaging to indicate the most appropriate treatment could be more rational. We report 2 cases of stroke with unknown onset time. In both cases, anamnesis and MR imaging indicated that we might still be within 6 hours from stroke onset, with salvageable tissue. Arterial recanalization was successfully performed in both cases.
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Tourdias T, Rodrigo S, Oppenheim C, Naggara O, Varlet P, Amoussa S, Calmon G, Roux FX, Meder JF. Pulsed arterial spin labeling applications in brain tumors: practical review. J Neuroradiol 2008; 35:79-89. [PMID: 18206239 DOI: 10.1016/j.neurad.2007.11.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Few institutions use MRI perfusion without contrast injection called arterial spins labeling (ASL) routinely in clinical setting. After general considerations concerning the different ASL techniques and quantitative issues, we will detail a pulsed sequence that can be used on a clinical 1.5-T MR unit. We will discuss and illustrate the use of ASL in tumoral diseases for diagnosis, gliomas grading, stereotactic biopsy guidance and for follow-up after treatment.
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69
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Beaussier H, Naggara O, Calvet D, Joannides R, Iacob M, Laloux B, Bozec E, Guegan-Massardier E, Triquenot-Bagan A, Masson I, Oppenheim C, Boutouyrie P, Laurent S. 03.04 MECHANICAL AND STRUCTURAL CHARACTERISTICS OF CAROTID PLAQUES: ANALYSIS BY MULTI-ARRAY ECHOTRACKING SYSTEM AND MRI. Artery Res 2008. [DOI: 10.1016/j.artres.2008.08.292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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70
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Iosif C, Oppenheim C, Lamy C, Mas J, Méder J. Bilateral Hypoperfusion and Normal Diffusion MR Images in a Case of Acute Embolic Stroke. Cerebrovasc Dis 2008; 26:95-6. [DOI: 10.1159/000138338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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71
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Bertrand A, Oppenheim C, Lamy C, Rodrigo S, Naggara O, Mas JL, Meder JF. Comparison of optimized and standard diffusion-weighted imaging at 1.5T for the detection of acute lesions in patients with transient ischemic attack. AJNR Am J Neuroradiol 2007; 29:363-5. [PMID: 17974606 DOI: 10.3174/ajnr.a0802] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARY The high rate of normal diffusion-weighted imaging (DWI) in patients with transient ischemic attack (TIA) raises the question as to its sensitivity for detecting small ischemic lesions. We compared standard and optimized DWI in 36 consecutive patients with TIA. Optimized DWI was positive in more patients than standard DWI (19 versus 16; P < .001) and showed more lesions (56 versus 42; P = .002). At 1.5T, optimizing DWI decreases the rate of false-negative DWI in patients with TIA.
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Rodrigo S, Naggara O, Oppenheim C, Golestani N, Poupon C, Cointepas Y, Mangin JF, Le Bihan D, Meder JF. Human subinsular asymmetry studied by diffusion tensor imaging and fiber tracking. AJNR Am J Neuroradiol 2007; 28:1526-31. [PMID: 17846205 PMCID: PMC8134399 DOI: 10.3174/ajnr.a0584] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to improve our understanding of the subinsular white matter microstructural asymmetries in healthy right-handed subjects. Structural brain asymmetries could be related to functional asymmetries such as hemisphere language dominance or handedness. Besides the known gray matter asymmetries, white matter asymmetries could also play a key role in the understanding of hemispheric specialization, notably that of language. MATERIALS AND METHODS White matter asymmetries were studied by diffusion tensor imaging at 1.5T (41 diffusion-gradient directions; b-value set to 700 s/mm(2); matrix, 128(2); in-plane resolution, 1.875 x 1.875 mm; section thickness, 2.0 mm) and fiber tracking (BrainVISA software). The main white matter bundles passing through the subinsular area were segmented, and fractional anisotropy (FA) was measured along each of the segmented bundles. RESULTS In line with published results, we found an asymmetry of the arcuate fasciculus and the subinsular white matter, namely left-greater-than-right FA in right-handed controls. Furthermore, by segmenting major tracts coursing through this region, we showed that the subinsular portions of the uncinate fasciculus (UF) and the inferior occipitofrontal fasciculus (IOF) contribute to this FA asymmetry. Those tracts have been reported to be likely implicated in the language network. CONCLUSION Because the left hemisphere hosts language functions in most right-handers, the significant leftward asymmetry observed within the arcuate fasciculus, the subinsular part of the UF and IOF may be related to the hemispheric specialization for language.
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Hernalsteen D, Dignac A, Oppenheim C, Peeters A, Hermoye L, Duprez T, Cosnard G. Hyperacute intraventricular hemorrhage: detection and characterization, a comparison between 5 MRI sequences. J Neuroradiol 2007; 34:42-8. [PMID: 17316797 DOI: 10.1016/j.neurad.2007.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We aimed to evaluate the diagnostic accuracy of MRI for detecting early intraventricular hemorrhage (IVH) (within 6 hours after hemorrhage and to describe the MR features that allow diagnosis. For this purpose, MR data of 22 patients with hyperacute intraparenchymal hemorrhage were independently rated as negative or positive for IVH by two observers, in a blind, retrospective study taking computed tomography (CT) as providing the correct diagnosis of IVH. Sensitivity, specificity, intra- and interobserver agreement were assessed. On FSE-FLAIR, EPI-GRE-T2* and DWI images, all cases of IVH were correctly rated (sensitivity of 100%). For b0 EPI images, obtained from diffusion-weighted echo planar sequences, one case of IVH was missed by one reader (sensitivity of 88%). For T1 images, one patient was incorrectly rated negative for IVH by the two readers (sensitivity of 90%). Three forms of IVH were described, including clotted hematoma, layered hemorrhage and red blood cell deposit. When CT images were obtained within a time span of less than 3 hours after MRI, volume was assessed. Volume of hemorrhage on CT correlated best with DWI images but was underestimated on EPI-GRE T2* images.
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Oppenheim C, Ducreux D, Rodrigo S, Hodel J, Tourdias T, Charbonneau F, Pierrefitte S, Meder J. [Diffusion tensor imaging and tractography of the brain and spinal cord]. ACTA ACUST UNITED AC 2007; 88:510-20. [PMID: 17457261 DOI: 10.1016/s0221-0363(07)89850-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Diffusion tensor imaging is a magnetic resonance imaging technique that provides details on tissue microstructure and organization well beyond the usual image resolution. With diffusion tensor imaging, diffusion anisotropy can be quantified and subtle white matter changes not normally seen on conventional MRI can be detected. The aim of this article is to review the principles of diffusion tensor imaging and fiber tracking and their applications to the study of the brain, including Alzheimer disease, neuropsychiatric disorders, strokes, multiple sclerosis, brain tumors, and intractable seizures. Emerging applications to spinal cord disorders are also presented.
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Bertrand A, Oppenheim C, Moulahi H, Naggara O, Rodrigo S, Patsoura S, Adamsbaum C, Pierrefitte S, Meder JF. [Diffusion-weighted imaging of the brain: normal patterns, traps and artifacts]. ACTA ACUST UNITED AC 2007; 87:1837-47. [PMID: 17213768 DOI: 10.1016/s0221-0363(06)74164-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Owing to its rapid acquisition time and high sensitivity, diffusion-weighted imaging has turned into a routine sequence for brain imaging. This is the case not only for stroke, but also for various diseases such as abscesses or tumors. Being aware of the artifacts is important for optimal interpretation. After a brief review of the normal patterns, the most frequent artifacts, inherent to the echoplanar imaging technique, are described and we provide suggestions to avoid them. Most current traps are caused by T2-weighting of the diffusion images; the key for avoiding erroneous interpretation relies on the ADC map.
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