Individualized HRCT-guided posterior internal auditory canal wall resection via the retrosigmoid approach for acoustic neuroma.

American journal of otolaryngology 2026 Vol.47(3) p. 104831

Yang H, Zeng L, Yu J, Zeng L

Abstract

[OBJECTIVE] To describe a high resolution computed tomography (HRCT) guided, individualized planning technique for posterior internal auditory canal (IAC) wall drilling during retrosigmoid microsurgical resection of unilateral acoustic neuroma and to report anatomical and surgical outcomes in a retrospective observational case series.

[METHODS] This retrospective observational surgical techniques included 256 patients with unilateral acoustic neuroma who underwent preoperative and postoperative HRCT. Imaging data were acquired and analyzed using a workstation, and evaluation of the IAC and individualized surgical planning were based on preoperative HRCT.

[RESULTS] To preserve labyrinth integrity, the posterior IAC wall drilling angle (α) was planned on a patient-specific basis using preoperative HRCT. Across the cohort, the mean planed angle was 42.3° ± 7.6°. In this series, the IAC resection rate was 76.3% and the gross total resection rate was 94.1%, while labyrinth integrity was maintained in all patients.

[CONCLUSION] In this retrospective observational surgical techniques study, HRCT-based preoperative planning provided a practical framework for microsurgical resection of the posterior wall of the IAC in acoustic neuroma surgery. This approach is hearing-preservation-oriented and may support facial and vestibulocochlear nerve-preservation-oriented surgery; however, standardized postoperative audiometric outcomes were not uniformly available for formal hearing outcome analysis.