Nuances in transcanal endoscopic surgical technique for glomus tympanicum tumors

Objective: To describe the utility and nuances of transcanal endoscopic surgery (TCES) on glomus tympanicum tumors from a single surgeon's experience. Patients/intervention: Twelve patients, eight female and four males, diagnosed pre-operatively with glomus tympanicum tumors. They all underwent endoscopic resection by a single surgeon. Main outcome measures: Feasibility of endoscopic resection of glomus tympanicum tumors without conversion to a microscopic approach. Secondary outcomes include tumor stage, pre and post-operative audiometry, vertigo, sensorineural hearing loss (SNHL) and integrity of the facial nerve, ossicles, chorda tympani and tympanic membrane. Results: Twelve patients underwent TCES, eight patient's pathology results were glomus tympanicum, ranging from Glasscock-Jackson grade I-III. Due to loss in follow up, 6/8 patients had complete audiometric data, which were analyzed. Average pre-operative air-bone-gap (ABG) was 5.41 compared to post-operative ABG of 5.08 (p > 0.89). No patients resulted in any, post-operative vertigo, tinnitus, SNHL, facial nerve injury or chorda tympani nerve injury. Two patients had intentional tympanic membrane perforations secondary to tumor adherence to the membrane. They were repaired with tragal perichondrium graft. No patients have had any recurrences. Conclusions: Endoscopic resection of glomus tympanicum tumors is a feasible and effective, alternative visualization modality for the neurotologist. Surgical pearls are described herein.