Antiviral Prophylaxis for Delayed Facial Nerve Palsy Following Vestibular Schwannoma Resection: Single Institutional Series With Systematic Literature Review and Meta-Analyses of 7136 Patients

Rachel Blue; Reinier Alvarez; Brianna Hines; Ross Moseley; Ekshika Patel; Annika S Witt; Yan Zhou; Lindsey Freeman; Yue Wang; Patrick Hosokawa; Samuel Gubbels; A Samy Youssef

doi:10.1227/neu.0000000000004096

Antiviral Prophylaxis for Delayed Facial Nerve Palsy Following Vestibular Schwannoma Resection: Single Institutional Series With Systematic Literature Review and Meta-Analyses of 7136 Patients

Neurosurgery. 2026 Jun 1. doi: 10.1227/neu.0000000000004096. Online ahead of print.

Authors

Rachel Blue^{1

2}, Reinier Alvarez¹, Brianna Hines³, Ross Moseley⁴, Ekshika Patel⁴, Annika S Witt⁴, Yan Zhou⁴, Lindsey Freeman¹, Yue Wang⁵, Patrick Hosokawa⁵, Samuel Gubbels⁶, A Samy Youssef^{1

6}

Affiliations

¹ Department of Neurosurgery, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.
² Current Affiliation: Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.
³ School of Medicine, Tulane University, New Orleans, Louisiana, USA.
⁴ University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.
⁵ Center for Innovative Design and Analysis, Department of Biostatistics and Informatics, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA.
⁶ Department of Otorhinolaryngology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.

PMID: 42223257
DOI: 10.1227/neu.0000000000004096

Abstract

Background and objectives: Delayed facial nerve palsy (DFNP) is a recognized complication of vestibular schwannoma resection, with proposed mechanisms including viral reactivation, inflammation, and ischemia. Elevated herpes simplex virus and varicella zoster virus titers and responses to antiviral therapy have been reported, but evidence supporting prophylactic antiviral use remains limited. We evaluated DFNP incidence, risk factors, and outcomes following antiviral prophylaxis using a systematic review, meta-analysis, and institutional cohort.

Methods: We conducted a 2-part study: (1) retrospective analysis of patients undergoing vestibular schwannoma resection by a single surgeon (October 2014-October 2024) and (2) systematic review and meta-analysis of DFNP incidence and prophylactic strategies. A standardized valacyclovir protocol (1000 mg TID for 7 days starting 3 days preoperatively) was implemented in June 2015. DFNP was defined as a ≥2-grade House-Brackmann (HB) worsening occurring between postoperative days 5 to 30. PubMed and Embase were searched in February 2025 per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results: In the institutional cohort (n = 301), DFNP occurred in 5%, with no significant difference among patients receiving valacyclovir (6% vs 3%, P = .42). Early postoperative HB grades III-IV was the strongest predictor of DFNP with odds ratio 6.07 (P = .01). Meta-analysis of 28 studies (n = 6835), combined with our cohort (total n = 7136), demonstrated a background DFNP incidence of 12.8%. Over 80% of patients recovered to HB grades I-II regardless of treatment. Five studies, including our cohort, provided comparative prophylaxis data; pooled analysis of antiviral prophylaxis showed a significantly reduced risk of DFNP (relative risk 0.73, CI 0.60-0.88; number needed to treat 16).

Conclusion: DFNP is an unpredictable but typically self-limited postoperative complication. Although no significant prophylactic effect was observed in our institutional cohort, pooled data suggest that antiviral prophylaxis may meaningfully reduce DFNP incidence, supporting its perioperative use and the need for larger prospective studies.

Keywords: Antiviral prophylaxis; Delayed facial nerve palsy; Facial nerve outcomes; House-Brackmann; Postoperative complications; Valacyclovir; Vestibular schwannoma.