Dysphagia Characteristics in High Versus Low Vagal Unilateral Vocal Fold Paralysis

Objective: To compare instrumental swallow assessment findings and diet recommendations in high versus low vagal unilateral vocal fold paralysis (UVFP). Methods: Retrospective review of patients with UVFP who underwent instrumental swallow assessment, September 2019–February 2024. Demographics, Eating Assessment Tool-10 (EAT-10) score, flexible laryngoscopy findings, instrumental swallow parameters, diet recommendations, treatment modalities, and posttreatment outcomes were analyzed. Results: Ninety-six patients were included: 28 (29%) high-vagal and 68 (71%) low-vagal UVFP. High vagal UVFP had a higher incidence of premature spillage (57% vs. 13%, p < 0.0001); residue (82% vs. 22%, p < 0.0001), penetration (89% vs. 35%, p < 0.0001), aspiration (50% vs. 22%, p = 0.013), modified diet (61% vs. 16%, p < 0.0001), and behavioral modifications (89% vs. 38%, p < 0.001) compared to low vagal UVFP. Thirty-one patients (32%) underwent injection laryngoplasty (16 high, 15 low vagal) with similar pretreatment prevalences of premature spillage, penetration, and aspiration, but a higher prevalence of residue in the high vagal group (100% vs. 53%, p = 0.002). Both groups improved posttreatment (high vagal: 63%–19%, p = 0.016; low vagal: 80%–7%, p = 0.001). Conclusion: High vagal UVFP is associated with greater swallowing dysfunction and higher prevalences of diet and behavioral modifications compared to low vagal UVFP. Treated high and low vagal subgroups had similar dysphagia profiles. Injection laryngoplasty improved aspiration, regardless of vagal level, although many patients continued to require behavioral modifications. Future studies are needed to identify predictors of poor functional swallowing outcomes in UVFP. Level of Evidence: 3.