HSC Section 6 Nov2016 Green Book

Reprinted by permission of Laryngoscope. 2014; 124(10):2371-2374.

The Laryngoscope V C 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Pharyngeal Weakness and Upper Esophageal Sphincter Opening in Patients With Unilateral Vocal Fold Immobility

Amanda S. Domer, MS, CCC-SLP; Rebecca Leonard, PhD, CCC-SLP; Peter C. Belafsky, MD, PhD, MPH

Objectives/Hypothesis: To evaluate pharyngeal strength and upper esophageal sphincter opening in patients with uni- lateral vocal fold immobility (UVFI). Study Design: Case control study. Methods: Charts of individuals with UVFI who underwent a videofluoroscopic swallow study were reviewed. To exclude confounding variables associated with pharyngeal weakness, inclusion was limited to patients with iatrogenic and idiopathic UVFI. Data abstracted included patient demographics, etiology of UVFI, pharyngeal constriction ratio (PCR), and upper esoph- ageal sphincter (UES) opening (UESmax). Data were compared to age/gender-matched controls with no history of dysphagia or UVFI. Discrete variables were analyzed using a chi-square test of independence, and an independent samples t test was used to compare the UVFI and control groups ( P 5 0.05). A one-way analysis of variance (ANOVA) was used to compare iatro- genic and idiopathic UVFI groups. Results: The mean age of the cohort (n 5 25) was 61 ( 6 14 SD) years and 52% was female. The etiologies of UVFI were iatrogenic (n 5 17) and idiopathic (n 5 8). Thirty-eight percent of UVFI patients (n 5 25) aspirated compared to 0% of con- trols ( P < 0.05). The mean PCR for the UVFI group was 0.14 ( 6 0.02) compared to 0.06 ( 6 .01) for controls ( P < 0.05). The mean UESmax for the UVFI group was 0.82 cm ( 6 0.04) compared to 1.0 cm ( 6 0.05) for controls ( P > 0.05). Conclusion: Individuals with UVFI of iatrogenic and idiopathic etiologies with subjective dysphagia demonstrate objec- tive evidence of pharyngeal weakness. The increased prevalence of aspiration in this population may not be solely the result of impaired airway protection. Key Words: Dysphagia, aspiration, vocal fold immobility, swallowing disorder, unilateral vocal fold immobility, UVFI. Level of Evidence: 3b. Laryngoscope , 124:2371–2374, 2014

INTRODUCTION Glottal competence is essential in airway protection during deglutition. If glottal closure is ineffective as a result of unilateral vocal fold immobility (UVFI), airway protection during the swallow may be compromised. UVFI may result from damage to the 1) brainstem nuclei, 2) vagus nerve, or 3) recurrent laryngeal nerve. Etiologies of UVFI include surgical trauma/iatrogenic (40%), tumor/neoplasm (30%), unknown/idiopathic (11%), trauma (8%), central nervous system dysfunction (4%), radiation (3%), inflammatory conditions (2%), and cardi- ovascular disease (2%). 1 Individuals with UVFI may present with aphonia (i.e., absence of voice), dysphonia (i.e., voice impairment), and/or dysphagia (i.e., swallow- ing impairment). From the Department of Communication Sciences & Disorders, University of South Florida ( A . S . D .), Tampa, Florida; and the Department of Otolaryngology–Head & Neck Surgery, University of California, Davis ( R . L ., P . C . B .), Sacramento, California, U.S.A. Editor’s Note: This Manuscript was accepted for publication May 20, 2014. The authors have no funding, financial relationships, or conflicts of interest to disclose. Send correspondence to Peter C. Belafsky, MD, PhD, MPH, Department of Otolaryngology–Head & Neck Surgery, University of Cali- fornia, Davis, 2521 Stockton Blvd, Suite 7200, Sacramento, CA 95817. E-mail: peter.belafsky@ucdmc.ucdavis.edu

The precise etiology of dysphagia in patients with UVFI is uncertain. It is generally accepted that UVFI results in diminished airway protection. If airway pro- tection is ineffective, an individual may aspirate mate- rial into the lungs, which may result in respiratory infection and/or death due to aspiration pneumonia. Approximately 33% to 42% of individuals with UVFI have been identified to aspirate. 2–5 Diminished airway protection is presumed to be the primary cause of swal- lowing dysfunction in patients with UVFI. 3,5 The integ- rity of other important biomechanics of the swallow, such as upper esophageal sphincter opening and pharyn- geal contractility, however, has not been adequately eval- uated in this patient population. Due to the highly intricate nature of the nerves and muscles in the phar- ynx and larynx, as well as the complex kinematics of the swallow, we hypothesize that features aside from impaired airway protection alone may contribute to increased occurrence of aspiration in this population. This has been hypothesized in previous studies, which have demonstrated subjective findings in addition to impaired glottic closure that the authors stated con- tributed to a patient’s increased risk of aspiration. One study that included patients with UVFI of both central and peripheral origins identified poor pharyngeal move- ment in patients with peripheral (i.e., recurrent laryn- geal nerve injury, vagus nerve injury, or idiopathic etiologies) UVFI. 4 Another study identified decreased

DOI: 10.1002/lary.24779

Laryngoscope 124: October 2014

Domer et al.: PCR and UES Opening in UVFI

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