Hearing Loss Progresses Faster in Patients With Growing Intracanalicular Vestibular Schwannomas.

Objective: To determine whether certain patient and tumor characteristics influence the progression of hearing loss in vestibular schwannoma (VS) patients.

Study Design: Retrospective study.

Setting: Tertiary referral center, Erasmus Medical Centre in Rotterdam, The Netherlands.

Patients: One hundred fifty-five patients referred from 2000 through 2010 with intracanalicular, small or medium sized, unilateral VS, managed without active treatment.

Intervention: Wait and scan protocol with sequential magnetic resonance imaging and audiometry.

Main Outcome Measures: Hearing loss as pure-tone average (PTA) in dB and progression of hearing loss expressed as the annual change in PTA or annual hearing decreasing rate (AHDR) in dB/yr.

Results: At presentation the mean hearing loss was 47 dB and the mean asymmetry between the tumor ear and the contralateral ear was 28 dB. The mean AHDR in wait and scan patients was 3.5 dB/yr (sd 4.6). Tumor growth was associated with the AHDR in patients with intracanalicular tumors. In patients with tumors extending into the cerebellopontine angle, we found a negative association between the AHDR and the PTA of the contralateral side. The explained variance, however, was low. No association was found between the AHDR and patient age, PTA in the tumor ear, tumor size, speech discrimination score at diagnosis or hypo-intensity of the cochlear fluids on magnetic resonance imaging.

Conclusion: There is no association between hearing deterioration and clinical characteristics in our 155 VS patients. Hearing loss is associated with tumor growth in intracanalicular tumors only.