Early voice therapy for unilateral vocal fold paralysis improves subglottal pressure and glottal closure

Purpose: In cases of unilateral vocal fold paralysis (UVFP), voice disorders caused by glottic insufficiency can lead to a considerable reduction in the patient's quality of life. Voice therapy (VT) is an effective treatment that must be started early after the onset of vocal fold paralysis. This study examined the effect of early VT for patients with UVFP occurring after esophagectomy. Materials and methods: Patients who had residual UVFP at 1 month postoperatively after esophagectomy for esophageal cancer between November 2014 and March 2017 were evaluated. Seventeen patients were divided into the VT group (n = 6) and non-VT group (n = 11). We compared these two groups and retrospectively examined the effect of early VT. The study endpoints included aerodynamic tests, laryngeal endoscopy, laryngeal stroboscopy, and glottal closure. All of these evaluations were performed at preoperatively and at 1 and 3 months postoperatively. Results: Subglottal pressure reduced notably in the VT group, and both the mean flow rate and maximum phonation time tended to improve after VT. Conversely, there were no significant differences in MFR and MPT in the non-VT group. Furthermore, although UVFP remained after VT, we achieved glottal closure for all three patients. Conversely, only two of the six patients with glottic insufficiency in the non-VT group achieved glottal closure. Conclusion: VT may be effective for improving impaired vocal function in patients with UVFP. It is reasonable to expect that VT can be initiated 1 month after the onset of vocal fold paralysis.