Dynamic Voice Optimization After Type I Thyroplasty Using a Novel Adjustable Implant: A Prospective Longitudinal Study

Objective: To evaluate the clinical outcome, safety and efficacy of the APrevent Vocal Implant System (VOIS) in patients with unilateral vocal fold paralysis (UVFP), with particular emphasis on the timing and impact of postoperative saline adjustments. Methods: This retrospective−prospective longitudinal study included 11 patients with chronic UVFP who underwent VOIS medialization thyroplasty (MT) under local anesthesia (n = 2) and general anesthesia (n = 9). Multidimensional voice parameters were analyzed preoperatively and at 1, 3, 6, and 12 months postoperatively. Statistical analyses included the Friedman test for repeated measures and the comparison of outcomes between pre- and each postoperative timepoints was evaluated with the Wilcoxon signed-rank test. Results: Significant and sustained improvements were observed across all multidimensional voice parameters. Mean mVHI-10 decreased from 31.7 ± 4.5 preoperatively to 5.8 ± 5.1 at 12 months, while mean MPT increased from 7.1 ± 3.8 to 14.4 ± 4.5 s (p < 0.05, r > 0.7). Acoustic parameters, including jitter, shimmer, and NHR, demonstrated progressive improvement over 12 months. A high proportion of patients (72.73%) underwent postoperative saline adjustment at a mean interval of 6.23 ± 1.23 months, beyond the early postoperative edema phase, with each adjustment yielding further enhancement in voice outcomes. No major complications, including airway obstruction or hematoma, were observed. Conclusions: VOIS MT is safe and effective, providing sustained improvements in multidimensional voice outcomes. The ability to perform postoperative saline adjustments enables dynamic optimization of glottal closure, reducing the need for revision surgery and addressing evolving laryngeal biomechanics. These findings support VOIS as a flexible, adjustable alternative to static medialization techniques and provide dynamic voice optimization in patients with UVFP.