Facial Nerve Outcomes After Secondary Treatments for Irradiated Vestibular Schwannoma

Sunday, September 29, 2024

8:12 AM – 8:18 AM EDT

Location: MBCC, 231

Disclosure(s):

Karen Tawk, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Tasha S. Nasrollahi, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Hamid R. Djalilian, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Introduction: To assess the prevalence of facial nerve (FN) paralysis in patients with vestibular schwannoma (VS) who underwent secondary treatment (radiosurgery (SRS) or microsurgery) following initial SRS and to determine facial nerve outcomes.

Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines and searched to identify studies analyzing FN function in patients receiving surgical or radiosurgery treatment after previous SRS for VS. All percentages are calculated according to the random effects model (REM), thus capturing uncertainty resulting from heterogeneity among studies.

Results: We evaluated 2,009 articles and selected 18 studies that met the inclusion criteria. Among 336 patients included into the analysis, 282 patients had surgery after SRS and 54 had SRS after failed SRS. We found that 74/240 patients [REM calculation of 25% (95% CI: 14-41%)] experienced new or worsened facial paralysis strictly related to any secondary treatment (reirradiation or microsurgery). In the surgical group, 70/186 patients [REM calculation of 36% (95% CI: 24-51%)] developed new facial paralysis or late worsening of FN functionality due to the secondary treatment; while in the radiation group, 2/54 patients [REM calculation of 4% (95% CI: 1-14%)] patients had new facial weakness. According to the REM calculation, after SRS retreatment, 94% (95% CI: 12-100%) of patients (after previous radiosurgery) demonstrated good FN functionality (grade 2/6 or lower), whereas microsurgery post-SRS led to an acceptable FN outcome in 61% (95% CI: 50-71%) of cases.

Conclusions: When proposing radiotherapy as upfront therapy, it should be stated that in case of failure, there is a 25% risk of worsened facial function due to any secondary treatment. The model (REM) predicted that following any retreatment (surgical or SRS), 55% of patients did not develop FN paralysis.

Presenting Author(s)

ES

Egidio Sia, MD

Trieste University, Italy

Disclosure information not submitted.

Co-Author(s)

KT

Karen Tawk, MD

Postdoctoral Fellow
University of California, Irvine
Mission Viejo, CA, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.
TN

Tasha S. Nasrollahi, MD

Resident
University of California, Irvine
Fresno, CA, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Senior Author(s)

Mehdi Abouzari, MD, PhD

Assistant Professor
University of California, Irvine
Orange, CA, United States

Disclosure information not submitted.
HD

Hamid R. Djalilian, MD

Professor of Otolaryngology, Neurosurgery, and Biomedical Engineering, Director of Division of Neurotology and Skull Base Surgery
University of California, Irvine
Irvine, CA, United States

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.