gms | German Medical Science

Objective: To evaluate long-term vestibulocochlear function of patients (P) who were operated on unilateral VS via RSA and to find out which factors could have an influence on outcome.

Method: 64 patients were retrospectively enrolled in this study. Preop. assessment included patients history, current symptoms and clinical examinations. At follow-up a questionnaire was applied to evaluate current vestibulocochlear complaints including tinnitus, vertigo and balance disturbances (BD), comparing their intensity with the preop. status. Cochlear function was evaluated by audiometry. Vestibular function (VF) was evaluated using vidio-oculography (VOG) to assess spontaneous nystagmus and eye movements after caloric testing. CC was assessed by rotational chair test. (Significance level p<0.05).

Results: Mean age of patients was 51 years at surgery, mean tumor size was 22.4 mm and the mean follow-up was 77 months. Preoperatively 81% suffered from hearing impairment, but 66% still had useful hearing (UH), 40% suffered from vertigo, 50% from BD and 61% from tinnitus. 62% underwent a postop. rehab, but without standard vestibular training. At follow-up 28% had vertigo, 58% BD and 61% tinnitus. Patients showed in the audiometry a long-term postop. UH preservation rate of 52%. VOG showed that 80% had a complete vestibular paresis, 16% a vestibular hypofunction and 4% a normal VF. 84% showed CC, while 16% did not prove CC. Statistical analysis showed that rate and intensity of vertigo at follow-up decreased significantly comparing to the preop. course, p=0.000. Patients who didn’t show CC at follow-up complained significantly more frequently of BD than those who showed CC, p=0.035. In the logistic regression, risk of developing a postop. non-UH increased with initial tumor size by a factor of 2.2 every 10 mm, p=0.020. Patients age raised risk of developing a postop. non-UH by a factor of 1.7 every 10 years, p=0.039. A better preop. Hearing function increased the chance of keeping a postop. UH significantly, p=0.002. P who underwent rehab didn’t fare better, in terms of postop. Vestibular complaints and CC.

Conclusions: Young patients with small tumors and good preop. hearing seem to have better chances of keeping postop. UH. After resection of VS via RSA vertigo improves significantly, the majority have a complete vestibular paresis. Developing CC is not obligatory but a process, which might fail leading more frequently to BD. A rehab without vestibular training doesn’t seem to be effective in treatment of vertigo or BD.