[Unilateral dysplasia of the circle of Willis with multiple distal stenoses (author's transl)].

Neurological and clinical examinations were found to be normal in a woman aged 40 years who had had a single generalized epileptic seizure. Rediological examinations demonstrated a spiral-shaped calcification above and laterally to the left sella turcica. This corresponded to changes in the C 1 segment of the left carotid sinus, which was partly stenosed distally, with left unilateral abnormalities of the circle of Willis and multiple distal stenoses of the left sylvian and vertebro-basilar arteries. Scanning demonstrated that these had been present for a long time, but it is not possible to establish the diagnosis on an etiological basis as no similar radiological findings have been published.