Quantitative Measurement of Dysphonia Severity in Patients With Stroke With Unilateral Vocal Cord Palsy

Unilateral vocal cord palsy (UVCP) is frequently observed in patients with stroke. This study aimed to evaluate the association between objective dysphonia severity and the classification of UVCP in patients with stroke by objectively and quantitatively measuring their phonetic function. We recruited patients with UVCP diagnosed using laryngoscopy after stroke. Subgroups were divided according to UVCP type, and the dysphonia severity index (DSI) and maximum phonation time (MPT) were measured to objectively evaluate dysphonia. The DSI and MPT were compared between subgroups using analysis of variance with Tukey's honest significant difference post hoc test. In total, 103 patients with stroke and UVCP were recruited. We found that a higher UVCP severity possibly had to do with lower DSI and MPT values. We objectively confirmed that phonetic function was worse in patients with stroke with higher UVCP severity, and the DSI and MPT tests can be helpful in determining the severity and need for additional evaluation.