HSC Section 6 Nov2016 Green Book

Fig. 1. Rating sheet for evaluators.

Despite the acknowledgment of variability in the laryngoscopic appearance of VFP implicit in these terms, no widely accepted rating system, or even a consistent, unified vocabulary to describe such variability exists. Consistency and reproducibility is fundamental in the evaluation and comparison of cases, their outcomes, and their treatment; even a brief reflection on the House- Brackmann scale for grading facial paralysis reveals the broad potential utility of such a standardized approach. The goal of this investigation was to evaluate character- istics of the laryngoscopic appearance of VFP with respect to inter- and intra-rater consistency, and to identify features for which clinical consensus exists, which might lend them- selves to a useful, standardized description system for VFP. Strobovideolaryngoscopies of patients with a clinical diag- nosis of VFP based on history, physical examination, and laryngoscopy were selected from a corpus of such examinations recorded during the course of routine evaluation. All recording was made under stroboscopic light using either a rigid glass rod peroral laryngoscope (Model 9106; KayPentax, Lincoln Park, NJ) or a distal chip flexible transnasal laryngoscope (VNL- 1170K; Pentax Medical, Montvale, NJ). Only patients with VFP of known cause were included. Nineteen had pathology or injury limited to the recurrent laryngeal nerve, and three had MATERIALS AND METHODS Selection of Examinations

paralysis from vagal neuropathy. For inclusion, the examination had to feature a sustained, unobstructed view of the glottis, ary- tenoids, aryepiglottic folds, and pyriform sinuses. A 20-second sample of each exam, containing at least one example each of phonatory adduction and postphonatory abduction as well as several cycles of phonatory vibration, was selected and saved. The pitch and intensity capabilities of patients were variable from exam to exam, as one would expect in cases of VFP. How- ever, as evaluators’ ratings of identical examinations were assessed in this study, no effort was made to standardize these parameters among examinations. Patients who had been treated for their VFP in any way, including injection augmentation, framework surgery, and rein- nervation were excluded. Cases of vocal fold paresis in which significant gross vocal fold mobility remained, even if it was clearly less than normal, were excluded. The authors recognize that the distinction between paralysis and paresis is not always sharply defined and does not necessarily reflect the underlying neurologic status. Each exam was numbered, and randomly ordered lists of these exams, one for each potential reviewer, were generated. In each list, three exams were selected to be repeated by a random number generator, which created a new set of three numbers for each of the reviewers and brought the total number of exams to 25. Therefore, every reviewer had a randomly selected series of repeat examinations to test their intra-rater reliability. The pur- pose of de novo, random selection of the repeat exams for every reviewer was to eliminate any possibility that one exam might be more easily identified on repeat viewing than the others. Such a scenario would bias the entire sample and yield an artificially

Laryngoscope 120: July 2010

Rosow and Sulica: Laryngoscopy of Vocal Fold Paralysis

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