Endolymphatic sac: possible role in autoimmune sensorineural hearing loss.

Histologic examination of the temporal bone of a patient with Wegener's granulomatosis showed involvement of the vessels of the endolymphatic sac (ELS) but no involvement of the vasculature of the rest of the inner ear. Autoimmune sensorineural hearing loss in this patient may have been due to interference of antigens and antibodies with the filtering capacity of the ELS, leading to imbalance of inner ear fluids. Histologic findings reemphasize that the cochlea and ELS have different blood supplies.