Laryngeal Reinnervation Techniques for Unilateral Vocal Fold Paralysis-Clinical Outcomes and Surgical Approaches: A Systematic Review and Meta-Analysis.

Background: Laryngeal reinnervation is a promising therapeutic option for unilateral vocal fold paralysis (UVFP). However, the efficacy of the different techniques remains controversial.

Objectives: To systematically evaluate clinical outcomes and surgical approaches employed for laryngeal reinnervation in UVFP, using both objective and subjective parameters.

Methods: A systematic review was conducted in accordance with PRISMA guidelines. PubMed/MEDLINE, Embase, the Cochrane Library, and Web of Science were searched for studies published between 2011 and 2024. Study quality was assessed using the Cochrane Risk of Bias Tool and the Newcastle-Ottawa Scale. A meta-analysis was performed for maximum phonation time (MPT) and the Voice Handicap Index (VHI).

Results: Twenty-six studies comprising 956 patients were included: 23 observational studies, two clinical trials, and one randomized controlled trial. The most frequently reported technique was the ansa cervicalis-to-recurrent laryngeal nerve anastomosis, as reported in 17 studies. MPT significantly improved from a baseline of 7.36 to 12.8 seconds at 6 months and remained stable at 11.7 seconds at 12 months, with moderate heterogeneity (I² = 65.6%-76.7%). VHI scores decreased significantly from a baseline of 47.0 to 16.6 at 6 months and 19.4 at 12 months, despite high heterogeneity (I² > 90%). Follow-up durations ranged from 3 months to 12 years, with minimal complications reported.

Conclusions: Laryngeal reinnervation demonstrates effectiveness in improving both objective and subjective outcomes in UVFP. Our updated literature synthesis underscored the value of reinnervation in UVFP and how an urgent need for standardized outcome measures and multicenter randomized trials is required to define its optimal role among emerging surgical alternatives.