VALUE OF MAGNETIC-RESONANCE-IMAGING IN WEST SYNDROME OF UNKNOWN ETIOLOGY

Magnetic resonance imaging (MRI) studies of 46 patients with West synd rome (WS) of unknown etiology were reviewed retrospectively. The crite ria for cryptogenic WS were met by 25 and 21 were considered symptomat ic because other types of seizure or psychomotor retardation were appa rent before spasm onset. Computed tomographic (CT) scans were normal i n 38 patients and showed diffuse atrophy in eight symptomatic patients . In five patients, MRI was more informative than CT, demonstrating on e case of delayed myelination and four cases of focal lesion. The foca l lesion in 2 of these patients was similar on MRI consisting of poor gray-white matter demarcation in the parieto-occipitotemporal region. Surgical resection was performed in one because of intractable seizure s, and neuropathological examination revealed cortical dysplasia. The remaining two cases with focal lesion had increased signal intensity o n T2-weighted images in the posterior frontal cortex and in the tempor al lobe, respectively. Our data indicate that MRI is useful in some ca ses of WS, especially in demonstrating focal corticosubcortical lesion s not visible on CT scan