Risk Factors for Delayed Facial Palsy Following Microvascular Decompression in Hemifacial Spasm: A Systematic Review and Meta-Analysis.

Abstract

Delayed facial palsy (DFP) remains a significant postoperative complication following microvascular decompression (MVD) for hemifacial spasm. However, the underlying mechanisms of DFP remain unclear. This study aimed to determine the incidence, duration, and latency of DFP onset following MVD. A secondary objective was to identify risk factors associated with DFP in this context. We conducted a systematic review and meta-analysis by searching PubMed, Embase, Web of Science, Cochrane Library, WanFang, and CNKI from inception through November 24, 2024, with data retrieval completed on January 10, 2025. Eligible studies were quantitative and original, reporting potential risk factors for DFP after MVD in patients with hemifacial spasm. A single-arm meta-analysis evaluated the incidence, duration, and latency of DFP. Meanwhile, a multivariate meta-analysis identified independent risk factors. Fifteen observational studies comprising 5262 MVD cases and 494 DFP events met inclusion criteria. The pooled incidence of DFP was 9% (95% confidence interval [CI]: 7-10). The average duration of DFP was 84.8 days (95% CI: 23.4-146.2), and the mean latency from surgery to onset was 10.9 days (95% CI: 4.7-17.1). Multivariate meta-analysis of nine studies using adjusted data identified facial nerve indentation (odds ratio [OR] = 12.78, 95% CI: 3.66-41.74), multiple offending vessels (OR = 6.95, 95% CI: 1.41-34.22), and longer disease duration (OR = 1.71, 95% CI: 1.01-2.89) as significant risk factors for DFP (P < 0.05). DFP is a relatively common complication after MVD, and facial nerve indentation, prolonged disease duration, and the presence of multiple offending vessels significantly increase DFP risk.