Evaluation of oculomotor tests in patients with tinnitus

Tinnitus as a symptom remains a serious multidisciplinary problem. Vertigo or dizziness is not noticed frequently in tinnitus patients, so vestibular function is not often studied. Because they are in close proximity to one another, the vestibular and hearing organs may influence each other. We decided to evaluate the results of the oculomotor reflex in tinnitus patients. We carried out clinical examinations and audiological and oculomotor tests in 50 tinnitus patients and 30 healthy persons. Such oculomotor tests as smooth-pursuit eye movement, optokinetic tests, and saccadic eye movement and gaze fixation were performed. Tinnitus was unilateral in 37 tinnitus patients (74%) and bilateral in 13 (26%). Twenty-two tinnitus patients (44%) reported previous remote episodes of vertigo and dizziness. Gaze-evoked nystagmus was absent in all cases. Morphological abnormalities and gain decreases in smooth-pursuit tests were recorded in 19 tinnitus patients (38%). Findings in the optokinetic test were incorrect in 10 (20%). The saccadic eye movement test showed disturbances in 18 tinnitus patients (36%). In 11 (22%), abnormal recordings were found in two tests and, in 10 (20%), abnormal recordings were found in all three tests. Our study suggests that computerized, quantitative electronystagmographic analysis in tinnitus patients should be interpreted carefully. A persistence of abnormal oculomotor recordings can suggest subclinical central vestibular system impairment.