RETRACTION CHOLESTEATOMA OF THE SINUS TYMPANI

Posteromedial retraction of the tympanic membrane, between the oval wi ndow superiorly and the round window niche inferiorly, results in the formation of an epithelium-lined pocket within the sinus tympanic rece ss. Failure to recognize posterior invagination of the tympanic membra ne intraoperatively leads to inadvertent tearing of the tympanomeatal flap at the level of the annulus with epithelial seeding of the middle ear and probably cholesteatoma recurrence. This article focuses on th e clinical manifestations and radiographic findings suggestive of sinu s tympanic epithelial retraction of the pars tensa and provides direct correlation between human cross-sectional temporal bone anatomy and o tomicroscopy. The surgical management of these challenging lesions inc ludes initial endaural access, external meatal bone removal posteromed ial to the tympanic annulus and anterior to the vertical portion of th e facial nerve, and middle ear ventilation after marsupialization of t he epithelial retraction. Although early tympanic membrane retraction can be treated with a ventilation tube, deep epithelial pockets may re quire additional surgical treatment. A method for the management of si nus tympanic cholesteatomas is demonstrated.