Vestibular compensation in patients with vestibular neuronitis

UNLABELLED: The aim of the study was to compare the clinical and ENG outcome in different time in patients with peripheral vestibular loss diagnosed as a vestibular neuronitis in order to establish degree of compensation. MATERIAL AND METHODS: Clinical observations were made on 30 patients with vestibular neuronitis treated from 1999 to 2003 year in ENT Department Medical University of Lodz. Mean age of patients was 37 +/- 11.7 years. In all of them clinical neurootological and audiological examination were performed. Balance system was evaluated by 4-channel ENG system during first two weeks after onset of the symptoms and later between 12-16 months. We compared clinical findings and ENG outcome applying modified vestibular index proposed by Toth et al., which defines the lesion extend and recovery during follow-up. RESULTS: A mean value of vestibular index in the first examination was significantly higher than in the second examination (11.3 +/- 2.7 vs. 4.0 +/- 1.6; p < 0.001). The recovery was found in clinical and ENG outcome except caloric test, in which canal paresis (more than 26%) was recorded in 19 patients (63.3%). The patients were classified according to vestibular index scores in the first examination as acute--subacute stage--20 patients and compensation stage--10 patients; in the second examination--as remission stage--19 patients, and compensation stage--11 patients. A comprison of vestibular index in each patient during follow-up revealed that 13 patients (43.3%) had presented dynamic recovery and changed acute--subacute stage to remission stage. In others a recovery was slower, so 13 patients (43.3%) changed acute-subacute stage to compensation stage and 4 patients (13.3%) stayed all the time in compensation stage. CONCLUSIONS: (1) Most of the patients with vestibular neuronitis had satisfactory recovery, evaluated by vestibular index. (2) These patients, in whom recovery was not enough, must be submitted to detail clinical and electronystagmographical evaluation in late period after peripheral vestibular loss. (3) Vestibular index may be useful in evaluation the extend of vestibular lesion and compensation status in patients with vestibular neuronitis.