Laryngoscopic and stroboscopic signs in the diagnosis of vocal fold paresis

To identify strobolaryngoscopic findings significant in the diagnosis of paresis.

Retrospective cohort study.

Fellowship-trained laryngologists reviewed 34 videostroboscopic examinations (24 with paresis, eight without paresis, two repeat). They indicated presence or absence of paresis, including side and type, degree of confidence in diagnosis, and ranked clinical findings that influenced diagnosis by order of importance. Fleiss's κ was used to assess inter-rater agreement for paresis presence, side, and type. Clinical findings compelling in diagnosis were tabulated and described. Confidence levels for side and type were compared by analysis of variance/Kruskal-Wallis tests and post hoc pairwise comparisons.

Thirty-one laryngologists completed the review. Inter-rater agreement on presence or absence of paresis was fair at 0.334 (Fleiss's κ). Fourteen examinations were diagnosed with paresis by >70% of raters and considered strong paresis-candidate exams. Diagnosis of paresis side and type were inconsistent, although with statistically significant differences in confidence ratings (unilateral vs. bilateral, recurrent laryngeal nerve [RLN] vs. superior laryngeal nerve [SLN], RLN vs. mixed RLN/SLN). Laryngoscopic and stroboscopic findings with the strongest association with paresis were vocal fold motion anomalies, vocal fold degeneration, glottic insufficiency, and mucosal wave anomalies.

Most laryngologists use strobolaryngoscopy for diagnosis of paresis. Although certain clinical findings were found to be associated with diagnosis, most commonly vocal fold motion anomalies, these varied among raters, especially when determining sidedness and nerve involvement. Future studies should expand the discussion and consideration of strobolaryngoscopic factors and adjunct functional and objective measures to develop a heuristic algorithm for diagnosis of paresis.

4. Laryngoscope, 127:2100-2105, 2017.