This report concerns a patient with ophthalmoplegia, ataxia and hyporeflexia (Fisher's syndrome) with a lesion in the midbrain tegmentum demonstrated by computerized-tomography (CT) scanning. Spontaneous recovery was almost complete 1 month after the onset. Based upon its strategic location, it is suggested that the lesion can explain the findings in the patient. The CT finding, if confirmed, will necessitate a reconsideration of our current pathogenetic views about Landry-Guillain-Barré syndrome in general and Fisher's syndrome in particular.