[Miller Fisher's syndrome. Clinical and experimental contribution].

A 19-year-old patient with acute idiopathic polyneuritis is described. Clinically, apart from ophthalmoplegia, areflexia and ataxia, the patient presented a serious bilateral and symmetrical deficiency of the VII-IX-X cranial nerve and hypanapallesthesia of trunk and extremities. Liquor examination showed albumino-cytological dissociation with an increase in liquor IgG; encephalic CT and encephalo-medullary NMR were normal; a neurophysiological study (EMG, PEV, BAER) was indicative of the PNS problems. Combined corticosteroid and plasmaferesis treatment produced complete clinical remission after about 3 months. The primary role of PNS involvement in this clinical entity is discussed.