Acoustic Analysis for Predicting Voice Recovery Following Injection Laryngoplasty in Patients With Unilateral Vocal Fold Paralysis.

Objectives: This study aimed to evaluate the efficacy of injection laryngoplasty (IL) in improving voice quality in patients with unilateral vocal fold paralysis (UVFP), as measured by acoustic parameters.

Methods: A cohort of 177 patients with UVFP underwent preIL and postIL assessment using maximum phonation time (MPT), Acoustic Voice Quality Index (AVQI), and Acoustic Breathiness Index (ABI), in conjunction with auditory-perceptual (A-P) ratings and the Voice Handicap Index-10 (VHI-10).

Results: Significant improvements were observed across all acoustic and perceptual measures following IL. MPT, AVQI, and ABI, as analyzed using Praat, provided comprehensive quantification of voice recovery. All three measures showed high diagnostic accuracy, with area under the curve values of ≥ 0.73. Receiver-operating characteristic analysis identified effective cutoff values for MPT, AVQI, and ABI, confirming their predictive value for voice recovery.

Conclusion: The findings of this study support the integration of MPT, AVQI, and ABI in clinical practice for a more precise assessment of IL outcomes in patients with UVFP. Future research should involve larger sample sizes to investigate cause-specific recovery rates and the role of postIL voice therapy.