Saccadic and smooth-pursuit eye movement in neurootological diagnostic procedures

The origin of the generation of saccadic and smooth-pursuit eye movements has not been proved. The goal of the study reported here was to search for the connection of visuooculomotor reactions--saccades and eye-tracking test--with cerebellar damage. Using electronystagmography, we tested 11 patients treated with aminoglycosides because of pneumonia. After a mean of 21 days of pharmacological therapy, a neurological examination revealed cerebellar disability in all cases. On the basis of our previous studies, we suspected cortical Purkinje cell damage. In all tested patients, saccadic movements were disturbed: We observed overshoot, undershoot, and prolonged latencies. In seven patients, eye-tracking test results were not correct: We noted the degradation of the sinusoidal pattern most often. The results pointed to a connection between the generation of these two tested visuooculomotor reactions with cerebellar diseases possibly located in the cortex.