The Transmastoid Retrolabyrinthine Approach in Acoustic Neuroma Surgery: Our Experience in 189 Patients

Objective: This study aimed to describe our experience with the retrolabyrinthine or infralabyrinthine approach in acoustic neuroma surgery, and to discuss its advantages, limitations, complications, and the outcomes of hearing and facial function preservation. Study Design: This study was a retrospective analysis of all acoustic neuroma cases, operated with a retrolabyrinthine approach in our hospital. Setting: This study was conducted at a tertiary university hospital. Patients: In total, 189 patients underwent hearing preservation and acoustic neuroma surgery, operated through the retrolabyrinthine approach, in our department. The average age was 43.6 years; there were 105 women and 84 men. All patients had unilateral tumors, 99 occurring in the right ear and 90 in the left ear. Intervention: A retrolabyrinthine approach was performed in all 189 patients to remove vestibular schwannoma. Main Outcome Measures: All tumors graded I and II using Koos tumor grading with serviceable hearing when the speech reception threshold (SRT) was better than 50 dB, and word recognition scores of 50% or higher. Results: Considering the 189 patients, good exposure of the internal auditory canal was possible in all patients, with total removal of the tumor in all patients, even though it was necessary to sacrifice the posterior canal in 12 of the cases, all classified as Koss II. Hearing was preserved in 49.73% of patients; 1% had permanent grade II House–Brackmann facial paralysis. Conclusions: The retrolabyrinthine approach showed security during facial nerve manipulation, small chance of morbidity, and good proportion of hearing preservation when tumor are up to Koss I and II classification.