Change in hearing and tinnitus in conservatively managed vestibular schwannomas.

Objectives: The aim of this study was to evaluate the change of hearing and tinnitus in a group of conservatively managed unilateral vestibular schwannomas (VS).

Design: Retrospective case series review.

Setting: Tertiary referral otoneurological and skull base surgery department.

Participants: Seventy patients affected by unilateral VS with at least two audiograms available were retrospectively evaluated.

Main Outcome Measures: Changes in pure tone average (PTA), speech discrimination score (SDS), and tinnitus were analyzed.

Results: At diagnosis 16 patients (22.9%) had a PTA of 0 to 30 dB and 38 (54.4%) a PTA of 0 to 50 dB. At the end of the follow-up period, 9 patients (12.9%) had a PTA of 0 to 30 dB and 27 (38.7%) had a PTA of 0 to 50 dB, representing a hearing preservation rate of 56% and 70%, respectively. Of patients with both tonal and speech audiometry, 71.4% with class A hearing (PTA < 30 dB/SDS > 70%) maintained their initial hearing and 60% with class A or B hearing (PTA < 50 dB/SDS > 50%) maintained this useful hearing. Forty-two patients (60%) did not show a significant growth in their tumor over the period of observation. In this group of patients the mean PTA after a mean follow-up time of 40 months decreased from 44 dB HL to 50.8 dB HL, with a yearly rate of 2.47 dB HL. The chance of maintaining a PTA of 0 to 30 dB in this group of patients was 57.1% and a PTA of 0 to 50 dB was 81.4%.

Conclusions: In this group of patients affected by VS and managed conservatively with a mean follow-up of 33.3 months, the risk of losing eligibility for hearing preservation surgery was lower than 30%.