Third window syndrome – Classification, diagnosis, therapy

Abstract

Patients frequently present to the physician with hearing loss. Routine hearing tests include speech field (whisper test), tuning forks and pure tone threshold audiometry, which can identify the presence of sensorineural hearing loss, conductive hearing loss or a combination of both (mixed type). Conductive hearing loss can be a symptom of many different conditions. These include congenital or acquired malformations of the outer, middle and inner ear. If a conductive hearing loss with intact stapedial reflexes are recorded and in the absence of outer or middle ear pathology, then the third window syndrome should be considered. The cause is a bony defect on the otic capsule that acts as a’third window’, dissipating the incoming sound energy. Without the appropriate audiological and imaging tests, the diagnosis of the condition is challenging in clinical setting. Several surgical techniques have been described to treat the condition. The authors give a comprehensive review of the etiology, diagnosis and treatment of the disease presenting their initial experiences with 2 cases.