[Otoneurologic manifestations of congenital abnormalities of foramen magnum region].

The symptoms and signs of 38 cases of congenital abnormalities of foramen magnum region have been analysed. Twenty-six cases presented dizziness and dysequilibrium, among them 16 had spontaneous nystagmus. ENG investigation was made systematically in four cases with spontaneous and gaze nystagmus. Ocular dysmetria, decreased intensity of optokinetic nystagmus, abnormal smooth pursuit movement and failure of fixation suppression were observed. Causes of the abnormalities were reviewed. The pathophysiological bases for the changes in ENG were briefly discussed.