Long-Term Outcomes of Modified Endoscopic Transcanal Approach to Small Acoustic Tumors

Abstract

Objective: The management options for small acoustic tumors are still controversial, and surgery is indicated in a select number of patients only. This is to avoid unnecessary extensive operations and risk of complications. Endoscopic transcanal approach, which was recently introduced, can be an alternative option to overcome these challenges. We have developed a modified technique for endoscopic transcanal removal of small acoustic tumors with tympanoplasty using tragal cartilage and without the need to harvest abdominal fat for obliteration. There was also no need to do an ear cul-de-sac procedure compared with the previous method. We report the long-term outcomes of this approach.

Study design: Retrospective review.

Setting: Tertiary hospital.

Patients: Those who were diagnosed with small acoustic tumors between June 2016 and June 2022 were enrolled.

Interventions: Tumor removal via a Modified Endoscopic Transcanal Transpromontorial Approach (mETTA).

Main outcome measure: Tumor control rate, closure rate of tympanic membrane, and complications such as cerebrospinal fluid (CSF) leakage and facial palsy were analyzed. Operation time and hospital stay were also analyzed.

Results: Twenty-two patients with a mean age of 55.5 ± 9.4 years were enrolled. Eighteen were vestibular schwannomas (VS), two were intracochlear schwannomas (ICS), and two were with intravestibulocochlear schwannomas (IVCS). Gross total removal was achieved in 21 cases. One had developed significant CSF leakage, and the other patient complicated with permanent facial palsy. The tympanic membrane healed well in all patients, but three patients showed delayed healing until several months and treated conservatively. Mean operation time was 149.6 ± 48.4 minutes, mean hospital stay was 8.9 ± 4.5 days, and mean postoperative follow-up period was 42.0 ± 15.7 months.

Conclusion: Long-term results of modified endoscopic transcanal approach to small acoustic tumors are acceptable and comparable to classical treatments such as translabyrinthine approach or gamma knife radiation. This is an alternative option for smaller tumors warranting surgical removal and maintained cosmetic advantages.