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pathophysiology of VFP, it has proved particularly disap- pointing as a prognostic tool, at best only partially helpful in informing treatment of individual patients. This study was undertaken with the understanding that any re-examination of the laryngoscopy of VFP must be carried out using a commonly agreed-upon array of findings. The evolving discussion about vocal fold paresis, or partial paralysis of the vocal fold, reveals clearly that lack of consensus regarding clinical findings prevents conclusions regarding diagnosis, much less prognosis, treatment, and outcomes. 13 No definitions of the terms used were provided to the reviewers for the simple reason that no such defini- tions exist. The terms used in this study have entered the literature informally, and the medical discourse has generally assumed that a broad and consistent under- standing of these descriptors exists. This study is a formal testing of that assumption. This investigation reveals that the evaluation of lar- yngoscopic appearance of VFP remains a personal and individual activity. As demonstrated by multiple correla- tion calculations, most evaluators were relatively consistent in their own evaluations across the entire range of features presented. These results were roughly equivalent to those of Rosen, who found that two thirds of voice professionals reviewing stroboscopic exams had intra-rater reliability scores less than 0.80. 14 Thus, it is possible that individual practitioners might use laryngo- scopic features to analyze cases for diagnosis, as for example to identify degree of denervation, distribution of involvement across laryngeal muscles, and for selection and timing of treatment in a reasonably reliable manner. It remains to be proven, of course, that pathophysiologic aspects such as degree and distribution of neural com- promise indeed have consistent laryngoscopic correlates. Incidentally, this study does not demonstrate whether individual observations across multiple examinations are reliable, or if changes over time in the same case can be consistently identified. On the other hand, inter-rater variability revealed considerable lack of consensus regarding all aspects but salivary pooling, bowing, and a simplified rating of the degree of glottic insufficiency. Our study might even have been biased in favor of greater inter- rater agreement by the inclusion of the audio track in the video samples sent to reviewers. Such additional information might provide clues to blinded reviewers who are ultimately being studied for their video per- ceptual analysis alone. Future work in this area will require removal of all audio from samples sent to reviewers. Not only is this lack of agreement discour- aging for the development of a unified rating system for this disorder, it also calls into question existing assumptions in the literature about consensus in the rating of features such as posterior gap (an important factor in the selection of patients for arytenoid adduc- tion surgery), vocal fold height (hypothesized to be relevant to rehabilitation technique), and other fea- tures referred to in the discussion of the evaluation of unsatisfactory results of medialization. 7,15–17 General- izations from study to study might be compromised by

patient populations that are not comparable or equiva- lent. Also, treatment recommendations or descriptions of outcome based on laryngoscopic features are likely to be of limited utility. The prospects for agreement on vocal fold paresis, where clinical variability would be expected to be greater than in VFP at the same time that the degree of abnormality would be less, appear to be extremely poor. Based on our results, degree of glottic insufficiency, vocal fold bowing, salivary pooling, and perhaps to a lesser extent volitional adduction, vocal fold tone, and vocal fold atrophy appear to be the best candidates for development into a standardized system of rating VFP. A rating or classification system for VFP based on only the three most consistently appreciated criteria might not be discriminating enough to be useful in diagnosis or treatment. We hypothesize that more formal develop- ment of rating categories, including explicit definitions and examples, would generate greater inter-rater agree- ment, for the terms and concepts evaluated in this investigation have received relatively little formal atten- tion despite commonplace clinical use. We intend to explore this further before trialing an integrated rating system. At the same time, we recognize the possibility that individual variation in laryngeal anatomy and pos- sibly in innervation, and the heterogeneity of neuropathic dysfunction might yet defeat such an effort. CONCLUSION However, although individuals are often consistent in their own evaluation of laryngoscopic features of VFP, little consensus appears to exist among physicians regarding these same findings. This raises the possibility that many assumptions about the significance of lar- yngoscopic features might not be reliable. This is an obvious challenge to arriving at a unified understanding of the laryngoscopic appearance of the disorder and will need to be addressed. Results suggest that degree of glottic insufficiency, vocal fold bowing, and salivary pooling appear to be lar- yngoscopic features in cases of VFP with the highest inter-rater reliability. With further investigation and standardization, these might form a basis for the devel- opment of a clinically useful rating scheme. Acknowledgments We gratefully acknowledge the participation of the following as raters or consultants in this study: Drs. Linda Gerber, Gregory Postma, Michael Johns, Edward Dam- rose, Marshall Smith, Tanya Meyer, Gaelyn Garrett, Rich- ard Kelly, Mark Courey, Seth Dailey, Ajay Chitkara, Sid Khosla, Pieter Noordzij, Libby Smith, Phillip Song, James Thomas, Albert Merati, Andrew McWhorter, Joel Blumin, Michiel Bove, and Milan Amin.

BIBLIOGRAPHY 1. Semon F. Clinical remarks on the proclivity of the abductor fibres of the the recurrent laryngeal nerve to become

Laryngoscope 120: July 2010

Rosow and Sulica: Laryngoscopy of Vocal Fold Paralysis

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