Improvement in swallowing safety after injection laryngoplasty in patients with unilateral vocal paralysis complicated with aspiration

Abstract

The benefit of injection laryngoplasty (IL) on voice for unilateral vocal fold paralysis (UVFP) is supported increasingly in literatures, yet less is known for swallowing. Also, prevalence of patient-reported dysphagia is substantially higher than instrumental studies. This prospective study focused on swallowing outcomes, with predetermined flexible endoscopic evaluation of swallowing (FEES) protocol that simulates daily life situation. Adult patients with UVFP and aspiration receiving IL were recruited. Voice outcome measurements, as well as swallowing outcomes including Eating Assessment Tool (EAT-10) and FEES, which challenged patients with different fluid volumes: 10mL, 20mL, and 90mL cup sipping were evaluated. Significant improvements were demonstrated in all voice outcomes. Significant changes were also presented inEAT-10 (P<0.01). Pre-operatively, penetration-aspiration scale (PAS) was 1.5±1.3, 1.9±1.7 and 2.3±1.8 for 10mL, 20mL and 90mL serial sipping, and improved to 1.1±0.3, 1.1±0.4 and 1.4±0.7 post-operatively (P<0.01). Safe swallowing (PAS ≤ 2) was achieved in all, except for one patient, who presented with a post-injection PAS of 4 (material enters the airway, contacts the vocal folds, and is ejected from the airway) on 90mL cup sipping, whose pre-injection PAS was 7 (residue in trachea). Maintaining swallowing function suitable for social environment is important. Our results demonstrated the feasibility of the predetermined FEES protocol, and positive effects of IL on both voice and swallowing outcomes.