Epineurial pseudocysts of the intratemporal facial nerve

Objective: Facial nerve pseudocysts are infrequently encountered during temporal bone surgery or neurotologic evaluation. This report describes the senior author's experience with epineurial pseudocysts of the intratemporal facial nerve. Study Design: Retrospective case review. Setting: Academic, tertiary referral center. Results: Epineurial pseudocysts were identified on computed tomography in the mastoid segment in seven patients during evaluation for profound sensorineural hearing loss or facial nerve symptoms. Histopathologic examination revealed fibroadipose tissue without nerve tissue in five cases that underwent excision. Conclusions: Facial nerve epineurial pseudocysts are uncommon, benign lesions of the mastoid segment. Surgical excision may be safely performed for facial motor symptoms or for cochlear implant placement.