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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an arteriopathy related to a genetic defect of the notch 3 gene on chromosome 19. The purpose of this study was to evaluate lesion distribution and volume using MR imaging and to correlate the lesion volume with the neurologic and neuropsychological findings.Twenty members of two families (14 with CADASIL as determined by linkage analysis, six healthy) were studied with MR imaging. Two observers evaluated the MR findings semiquantitatively and quantitatively. MR results were then correlated with neurologic and neuropsychological findings.A typical pattern of lesion distribution in patients with CADASIL was found: the frontal lobe was the site with the highest lesion load, followed by the temporal lobe and the insula. The total lesion volume on T1-weighted MR images correlated significantly with the degree of disability and the degree of impairment in neuropsychological functions (including attention, memory, and conceptual and visuospatial functions).In CADASIL patients, a common pattern of cerebral lesion distribution is found. The total T1 lesion volume is an important parameter to correlate with disability, as it may prove to be helpful in predicting the natural history of the disease.

In this study, we compared a fast fluid-attenuated inversion recovery (fast-FLAIR) sequence to conventional spin-echo (CSE) in the evaluation of brain MRI lesion loads of seven patients with clinically definite multiple sclerosis. Interleaved CSE (3000/20, 5 mm contiguous axial slices) and fast-FLAIR (9000/150/2200, 5 mm contiguous axial slices) sequences were performed on a 1.0 T machine. Lesions were counted consensually by two observers and then segmented independently by two other observers using a local thresholding technique, with subsequent manual editing in the case of poorly defined lesions. Four hundred and two lesions were detected in at least one of the two sequences: 128 were seen only on fast-FLAIR, 17 only on CSE. Forty-one lesions were larger on fast-FLAIR, while no lesion was considered larger on CSE. The numbers of periventricular (P = 0.05), cortical/subcortical (P = 0.02) and discrete (P = 0.05) lesions detected using fast-FLAIR were higher than those detected using CSE. The median lesion load was 7185 mm3 on CSE and 8418 mm3 on the fast-FLAIR, the average being 18% (range = 11.6-29%) higher on the fast-FLAIR images. Lesion contrast ratio was higher for lesions on the fast-FLAIR than on the CSE sequence (P < 0.0001). The percentages of poorly defined lesions which needed manual editing after the local thresholding technique was applied and the total time needed for the measurements were lower (P < 0.001) when fast-FLAIR images were used compared with CSE. This resulted in a reduced inter-rater coefficient of variation in measuring lesion volumes. Our data indicate that fast-FLAIR sequences are more sensitive than CSE in detecting multiple sclerosis lesion burden and that fast-FLAIR is a promising technique for natural history studies and clinical trials in multiple sclerosis.

We evaluated the correlations between cognitive impairment, clinical and brain magnetic resonance imaging (MRI) findings in 100 patients with multiple sclerosis (MS). The performance on one or more neuropsychological tests was abnormal in 47% of the 64 patients who completed the entire neuropsychological battery; the cognitive impairment was mild in 14 (22%) and severe in 16 (25%). Performance on any single neuropsychological test was unrelated to clinical parameters (age, duration of the disease, disability). The neuropsychological performance of relapsing-remitting patients was better than in patients with a chronic-progressive disease. The mean scores for almost all the neuropsychological tests were significantly lower in patients with severe ventricular dilatation and corpus callosum atrophy than in patients in whom these structures were little affected. Mean scores for WMS, performance Intelligence Quotient (IQ), total IQ and Token Test (TT) were also significantly correlated with the widening of cortical sulci and total lesional scores. Our data support the contention that the involvement of pathways that are critical for a given cognitive process as well as the progression of the axonal degeneration and sclerosis seem to play important roles in the pathophysiology of cognitive dysfunction in MS.

Brain MRI and multimodal evoked potentials (EPs) were obtained for 13 patients with benign multiple sclerosis and 13 patients with secondary progressive multiple sclerosis, matched for age and duration of the disease, to investigate the nature of the disability in multiple sclerosis. Patients with secondary progressive multiple sclerosis had significantly greater lesion loads for five of seven periventricular regions and for three of nine regions separate from the ventricles. Patients with secondary progressive multiple sclerosis also had more severe infratentorial atrophy scores (p = 0.04), whereas there were no differences between the two groups in number and extent of enhancing lesions. The frequencies were significantly higher and severities greater for multimodal EP abnormalities of all the modalities in patients with secondary progressive multiple sclerosis. At least one EP component was absent in 12 (92%) patients with secondary progressive multiple sclerosis but in only one patient (8%) with benign multiple sclerosis (p < 0.001). There was neurophysiological evidence for cervical cord involvement in eight (61%) patients with secondary progressive multiple sclerosis and in one with benign multiple sclerosis (p < 0.01). These data indicate that the total amount of lesions, the distribution, and the nature of the pathological process might all account for the development of disability in multiple sclerosis.

In this study, we investigated the relationship between multiple sclerosis lesion volumes measured from magnetic resonance imaging scans and image-slice thickness. The lesion volume was computed using a semiautomated thresholding technique from axial scans of the brain of varying slice thickness. Ten patients were studied, and in all cases the computed lesion volume increased with decreasing slice thickness (p = 0.01). Linear extrapolation from our data allowed the lesion volume at very small slice thickness to be estimated; this was found to be on average 20% greater than that obtained using a slice thickness of 5 mm. Furthermore, there were considerable differences in the percentage of change in lesion volume from patient to patient, and it would appear that there is a larger variation with slice thickness for patients with smaller lesions and higher lesion loads.

To evaluate whether hemispheric lesion distribution in multiple sclerosis is related to the uneven interhemispheric localisation of cerebral function, a 10 item self administered questionnaire evaluating hand preference and supratentorial brain MRI was obtained in 23 patients with clinically definite multiple sclerosis. The mean degree of hand preference was +74 (range -86 to +100). The median lesion volumes were 7275 (range 1045-22 440) mm(3) for the left hemisphere and 5385 (range 1010-19 490) mm(3) for the right hemisphere. The degree of hand preference correlated with the index of interhemispheric lesion distribution (P = 0.02). The data suggest that local events, possibly related to specialisation of hemispheric function, might be responsible for the increased vulnerability of the dominant hemisphere to the pathological process of multiple sclerosis.