Now You See It, Now You Don't: Laryngoscopy Findings of Paradoxical Vocal Fold Motion

The key exam finding in the diagnosis of paradoxical vocal fold motion (PVFM) is visualization of adduction of the true vocal folds during inspiration on laryngoscopy. This study aims to assess the reliability of visualizing PVFM on laryngoscopic exam.

Laryngoscopic exams of 60 patients being evaluated for PVFM were rated by 13 individual otolaryngologists at 2 different timepoints, 1 month apart. At the second timepoint, half of the exams were accompanied by a clinical history potentially suggestive of PVFM. Raters were asked to determine whether patients exhibited PVFM on the video shown, the degree of adduction of the vocal folds (complete, partial, or none), and the level of certainty with the diagnosis. Inter-rater and intra-rater reliability were calculated using Fleiss' and Cohen's kappa, respectively.

Interpretation of the presence of PVFM was quite variable. There was only fair inter-rater reliability (Fleiss' kappa = 0.36 at Timepoint 1 and 0.34 at Timepoint 2) and moderate to fair intra-rater reliability (median Cohen's kappa = 0.47 for videos without clinical history and 0.36 for videos shown with clinical histories). Ratings on degree of adduction were quite heterogeneous.

Though laryngoscopic findings of PVFM are the gold standard physical exam finding in support of diagnosis, only fair agreement was found when raters assessed laryngoscopy recordings for PVFM. Intra-rater reliability was also quite varied. Improvement in assessment of vocal fold function and understanding the role of clinical history in diagnosis may improve the care of patients with suspected PVFM.