Search results for "RESONANCE"
showing 10 items of 6625 documents
Brain atrophy and lesion load in a large population of patients with multiple sclerosis
2005
Objective: To measure white matter (WM) and gray matter (GM) atrophy and lesion load in a large population of patients with multiple sclerosis (MS) using a fully automated, operator-independent, multiparametric segmentation method. Methods: The study population consisted of 597 patients with MS and 104 control subjects. The MRI parameters were abnormal WM fraction (AWM-f), global WM-f (gWM-f), and GM fraction (GM-f). Results: Significant differences between patients with MS and control subjects included higher AWM-f and reduced gWM-f and GM-f. MRI data showed significant differences between patients with relapsing-remitting and secondary progressive forms of MS. Significant correlations bet…
Brain atrophy evolution and lesion load accrual in multiple sclerosis: a 2-year follow-up study
2009
Background To investigate in a large cohort of patients with multiple sclerosis (MS), lesion load and atrophy evolution, and the relationship between clinical and magnetic resonance imaging (MRI) correlates of disease progression. Methods Two hundred and sixty-seven patients with MS were studied at baseline and two years later using the same MRI protocol. Abnormal white matter fraction, normal appearing white matter fraction, global white matter fraction, gray matter fraction and whole brain fraction, T2-hyperintense, and T1-hypointense lesions were measured at both time points. Results The majority of patients were clinically stable, whereas MRI-derived brain tissue fractions were signifi…
Topodiagnostic implications of hemiataxia: An MRI-based brainstem mapping analysis
2007
The topodiagnostic implications of hemiataxia following lesions of the human brainstem are only incompletely understood. We performed a voxel-based statistical analysis of lesions documented on standardised MRI in 49 prospectively recruited patients with acute hemiataxia due to isolated unilateral brainstem infarction. For statistical analysis individual MRI lesions were normalised and imported in a three-dimensional voxel-based anatomical model of the human brainstem. Statistical analysis revealed hemiataxia to be associated with lesions of three distinct brainstem areas. The strongest correlation referred to ipsilateral rostral and dorsolateral medullary infarcts affecting the inferior ce…
ADC measurements in diffuse large B-cell lymphoma and follicular lymphoma: a DWI and cellularity study.
2012
Diffusion-weighted magnetic resonance imaging (DW-MRI) allows quantifying the random motion of water molecules in tissue by means of apparent diffusion coefficient (ADC) measurements. The aim of the study was to determine whether ADC measurements allow discrimination of diffuse large B-cell lymphoma (DLBCL) from follicular lymphoma (FL), and to examine the relationship between cellularity and ADC value of the tumor using DWI.Thirty-two patients with histologically proven non-Hodgkin lymphoma (21 with DLBCL and 11 with FL, 17 males and 15 females, mean age 62±13 years) underwent conventional MRI and DWI examination before treatment. The ADC values of DLBCL were compared to those of FL. The A…
Cerebellar parcellation in schizophrenia and bipolar disorder
2019
International audience; Objective: The cerebellum is involved in cognitive processing and emotion control. Cerebellar alterations could explain symptoms of schizophrenia spectrum disorder (SZ) and bipolar disorder (BD). In addition, literature suggests that lithium might influence cerebellar anatomy. Our aim was to study cerebellar anatomy in SZ and BD, and investigate the effect of lithium.Methods: Participants from 7 centers worldwide underwent a 3T MRI. We included 182 patients with SZ, 144 patients with BD, and 322 controls. We automatically segmented the cerebellum using the CERES pipeline. All outputs were visually inspected.Results: Patients with SZ showed a smaller global cerebellar…
Magnetic resonance imaging in primary cerebral neuroblastoma
1989
Hyperechogenicity of the substantia nigra in healthy controls is related to MRI changes and to neuronal loss as determined by F-Dopa PET
2009
Abstract Transcranial ultrasound (TCS) has been shown to reveal hyperechogenicity of the substantia nigra (SN) in Parkinsonian patients and in about 10% of healthy controls. It is hypothesized that SN hyperechogenicity in healthy subjects is a vulnerability marker for idiopathic Parkinson's disease (IPD). Although there is strong evidence that the echomarker results from increased local iron content, the exact pathophysiological mechanisms remain incompletely understood. Thus, prognostic impact can only be estimated. We examined 14 subjects with SN hyperechogenicity (SN+) (7 IPD patients and 7 controls) and 7 healthy controls without the echomarker (SN−) by a magnetic resonance imaging meth…
Electrophysiological and MRI findings in 2 patients with Listeria rhombencephalitis.
1997
Noninvasive assessment of Crohn's disease activity: a comparison of 18F-fluorodeoxyglucose positron emission tomography, hydromagnetic resonance imag…
2002
Detection of disease activity in Crohn's disease (CD) is of crucial importance for diagnosis and management of the disease. Noninvasive methods for monitoring are desirable and comprise hydromagnetic resonance imaging (hydro-MRI) and leukocyte scintigraphy. In addition, a recent case report indicated the potential of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to assess CD activity. However, comparative prospective studies are lacking.Between February, 1999 and August, 2000, 59 patients with CD were enrolled in a prospective study to assess disease activity by FDG-PET, hydro-MRI, and immunoscintigraphy with anti-nonspecific cross-reacting antigen 95 antigranulocyte antibod…
Missense PANK2 mutation without "eye of the tiger" sign: MR findings in a large group of patients with pantothenate kinase-associated neurodegenerati…
2011
Purpose: To present some unusual MR findings in a group of patients from the south-west of the Dominican Republic suffering from Pantothenate Kinase Associated Neurodegeneration (PKAN). Materials and Methods: Twenty patients and one preclinical case homozygous for the PANK2 mutation, 13 heterozygous gene carriers and 14 healthy volunteers were scanned prospectively using a 3 Tesla system. Results: All patients showed the typical signal reduction within the globus pallidus and the substantia nigra. A surprising finding was the absence of the bright spot (“tiger's eye”) in the medial part of the pallidum in 6 patients, but not in the preclinical case. Both fractional anisotropy (FA) and mean …