Quantification of hearing loss associated with superior semi-circular canal dehiscence.

INTRODUCTION: Superior semi-circular canal dehiscence (SSCD) is a known cause of hearing loss. This study quantifies hearing loss in SSCD ears in a frequency-specific fashion.

METHODS: A meta-analysis of English language literature pertaining to SSCD was performed, with extraction and evaluation of available human audiometric data. Our own institution's case series of SSCD patients was also similarly analysed. Hearing loss in SSCD ears was compared to same patient control ears and to age-matched normative audiometric data.

RESULTS: Ears with SSCD had statistically significant worse hearing as compared to both normative data and to own normal ear controls at 2000 Hz and below. The effect appears to diminish with increasing frequency.

DISCUSSION: The presence of statistically significant conductive hearing loss in the low frequencies was confirmed for SSCD ears. SSCD may also predispose ears to high frequency sensorineural hearing loss.