Demonstration of a little known cause of infantile epilepsy, occipital porencephaly, by computerized tomography (CT).

Among 500 epileptic patients studied by Computerized Tomography, 11 patients presented an occipital porencephaly (or a dilation of the occipital horn with a "porencephalic" aspect) sometimes associated with a ventricular dilation. These 11 patients represented 2.2% of our patients and 5% of those less than 20 yr of age which is frequent in relation to lesions of the same type having a different topography. Clinical and EEG studies of these 11 patients revealed hemiplegia or hemiparesis in 8 cases, hemianopsia in 7 cases, a severe partial epilepsy in 6 cases which was temporal in 5 patients, a secondary generalized epilepsy in 3 cases, and an epilepsy unable to be classified in 2 cases. The "porencephalies" responsible for these clinical signs are most likely of encephalomalacic origin, secondary to circulatory troubles in the peri- or postnatal period. Remillard et al. maintain that perinatal occlusion of the posterior cerebral artery is responsible. However, in our personal series, the results obtained from CT, PEG and angiography do not permit us to be as affirmative as to the vascular etiology responsible.