Postoperative Hearing Preservation in Patients Undergoing Retrosigmoid Craniotomy for Resection of Vestibular Schwannomas: A Systematic Review of 2034 Patients

• Published in: Neurosurgery Vol. 86; no. 3; pp. 332 - 342
• Main Authors: Preet, Komal, Ong, Vera, Sheppard, John P, Udawatta, Methma, Duong, Courtney, Romiyo, Prasanth, Nguyen, Thien, Kwan, Isabelle, Yang, Isaac
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01-03-2020; Copyright by the Congress of Neurological Surgeons; Wolters Kluwer Health, Inc
• Subjects: Acoustic neuroma; Brain cancer; Care and treatment; Craniotomy; Hearing disorders; Hearing loss; Methods; Neurosurgery; Patient outcomes; Patients; Prevention; Risk factors; Skull; Systematic review; Tumors; United States; Systematic review; Retrosigmoid craniotomy; Acoustic neuroma; Skull base surgery; Hearing loss; Vestibular schwannoma
• ISSN: 0148-396X; 1524-4040
• DOI: 10.1093/neuros/nyz147

Abstract
BACKGROUND
Vestibular schwannomas (VS) are benign tumors derived from Schwann cells ensheathing the vestibulocochlear nerve. The retrosigmoid (RS) surgical approach is useful to resect tumors of multiple sizes while affording the possibility of preserving postoperative hearing.
OBJECTIVE
To conduct a systematic review of published literature investigating hearing preservation rates in patients who underwent the RS approach for VS treatment.
METHODS
The PubMed, Scopus, and Embase databases were surveyed for studies that reported preoperative and postoperative hearing grades on VS patients who underwent RS treatment. Hearing preservation rates were calculated, and additional patient demographic data were extracted. Tumor size data were stratified to compare hearing preservation rates after surgery for intracanalicular, small (0-20 mm), and large (>20 mm) tumors.
RESULTS
Of 383 deduplicated articles, 26 studies (6.8%) met eligibility criteria for a total of 2034 patients with serviceable preoperative hearing, for whom postoperative hearing status was evaluated. Aggregate hearing preservation was 31% and 35% under a fixed and random effects model, respectively. A mixed effects model was used to determine hearing preservation rates depending on tumor size, which were determined to be 57%, 37%, and 12% for intracanalicular, small, and large tumors, respectively. Significant cross-study heterogeneity was found (I2 = 93%, τ2 = .964, P < .01; Q = 287.80, P = < .001), with rates of hearing preservation ranging from 0% to 100%.
CONCLUSION
Tumor size may have an effect on hearing preservation rates, but multiple factors should be considered. Discussion of a patient's expectations for hearing preservation is critical when deciding on VS treatment plans.