Ataxia in patients with Miller-Fisher syndrome: an inquiry into its mechanisms / 解放军医学杂志

ABSTRACT

Objective To explore the mechanisms and the location of the lesion which result in ataxia in patients with Miller Fisher syndrome (short for Fisher syndrome). Methods The clinical features were analyzed and auxiliary examinations were performed in 9 patients with Miller Fisher syndrome, while the pertinent literature was reviewed to analyze the possible mechanism responsible for ataxia in Fisher syndrome. Results All the nine patients manifested the specific clinical features of Fisher syndrome, including external ophthalmoplegia, ataxia, and attenuated or obsolescent tendon reflexes in all the limbs. 8 patients complained diplopia. The symptoms of internal ophthalmoplegia, mydriasis and loss of pupillary light reflex were found in 8 patients. Peripheral facial paralysis was found in 5 cases, glossopharyngeal nerve and vagus nerve paralysis were found in 1 patient. Cerebrospinal fluid (CSF) examinations were performed in 7 patients and showed increase in protein contemt in 6 patients, but CSF specimens in all patients were devoid of leucoytc. Electromyogram (EMG) indicated the existence of myogenic damages in 5 patients. Electroencephalogram was performed in 5 patients and no abnormity was found. Magnetic resonance imaging (MRI) or computerized tomography (CT) scanning of the brain did not reveal any significant abnormities in the cerebellum in all the patients. All the nine patients, who received dexamethasone and some other routine neuroprotective therapies, had a good prognosis. Conclusions On the basis of present study, no definite evidences to support that cerebellar lesion may cause ataxia in the patients with Fisher syndrome. It is assumed that external ophthalmoplegia may play a role in causing ataxia. Further studies are needed to ascertain the exact mechanisms responsible for ataxia in Fisher syndrome.