S219 – Japanese Otosclerosis Patient with Otospongiotic Lesions

Abstract

Objectives

Although it has been reported that the incidence of otosclerosis is much lower among Japanese patients and clinically the disease shows a reduced activity level, otosclerotic foci are sometimes detected in recent years. However, about the clinical significance, it is not still unclear. This study investigated the incidence of otosclerosis in Japanese patients with otosclerotic foci around the otic capsule, their audiometric correlation and surgical outcome.

Methods

We evaluated 59 patients (86 ears) with confirmed otosclerosis (at least one ear underwent surgery) in our hospital between 2001 and 2006. All patients underwent hearing and CT examination on the same day and hearing examination were repeated every 6 months regardless of whether the patient underwent surgery or observation only.

Results

Otosclerotic foci around the otic capsule were observed in 30.2% of the all ears in the Japanese otosclerosis. There was a correlation between the presence of otosclerotic foci and air-bone gap (p<0.05). In the surgical group, there was no significant difference between the patients with and without the presence of otosclerotic foci for the hearing improvements after stapes surgery. In the no-surgical groups, there was significant worsening of the hearing level in patients with otosclerotic foci in comparison to that of those without otosclerotic foci (p<0.01).

Conclusions

This incidence of Japanese otosclerosis patient with otosclerotic foci is not lower than those of Caucasians. Surgical outcome was not affecting by otosclerotic foci. It is concluded that CT examination is important for predicting the hearing level of patients.