Steven Bielamowicz1, Sheila V Stager. 1. Voice Treatment Center, Division of Otolaryngology-Head and Neck Surgery, The George Washington University, Washington, DC 20036, USA. sbielamowicz@mfa.gwu.edu
Abstract
OBJECTIVE/HYPOTHESIS: To determine whether specific laryngeal electromyography (LEMG) patterns in patients with unilateral vocal fold paralysis/paresis (UVFP) are related to etiology of injury, time from onset of injury, patient perception of symptom severity, acoustic measures, and laryngeal aerodynamic measures. STUDY DESIGN: This is a retrospective review of 75 patients. METHODS: Each patient received LEMG, acoustic and aerodynamic testing, and a subjective rating scale assessment (the Glottal Closure Index). Statistical analysis by groups were performed using both chi and single-factor analysis of variance testing. RESULTS: An iatrogenic etiology was associated with poor tone on LEMG (P = .05). Those individuals evaluated after 3 months after onset demonstrated more nascent units, a sign of reinnervation, compared with individuals evaluated before 3 months (P < .02). Individuals with fewer normal motor units on LEMG had significantly higher mean translaryngeal air flows (P = .044). Individuals with poor recruitment had significantly shorter maximum phonation times (P = .034) and higher mean flows (P = .044). Individuals with better laryngeal tone as noted on LEMG had significantly lower mean flows (P = .06). CONCLUSIONS: Specific LEMG patterns are related to the etiology of the UVFP and time course since recurrent laryngeal nerve injury. LEMG appears to reflect vocal fold muscle tone as seen on laryngeal function studies. In combination, these studies provide a cohesive assessment of laryngeal function in patients with UVFP.
OBJECTIVE/HYPOTHESIS: To determine whether specific laryngeal electromyography (LEMG) patterns in patients with unilateral vocal fold paralysis/paresis (UVFP) are related to etiology of injury, time from onset of injury, patient perception of symptom severity, acoustic measures, and laryngeal aerodynamic measures. STUDY DESIGN: This is a retrospective review of 75 patients. METHODS: Each patient received LEMG, acoustic and aerodynamic testing, and a subjective rating scale assessment (the Glottal Closure Index). Statistical analysis by groups were performed using both chi and single-factor analysis of variance testing. RESULTS: An iatrogenic etiology was associated with poor tone on LEMG (P = .05). Those individuals evaluated after 3 months after onset demonstrated more nascent units, a sign of reinnervation, compared with individuals evaluated before 3 months (P < .02). Individuals with fewer normal motor units on LEMG had significantly higher mean translaryngeal air flows (P = .044). Individuals with poor recruitment had significantly shorter maximum phonation times (P = .034) and higher mean flows (P = .044). Individuals with better laryngeal tone as noted on LEMG had significantly lower mean flows (P = .06). CONCLUSIONS: Specific LEMG patterns are related to the etiology of the UVFP and time course since recurrent laryngeal nerve injury. LEMG appears to reflect vocal fold muscle tone as seen on laryngeal function studies. In combination, these studies provide a cohesive assessment of laryngeal function in patients with UVFP.
Authors: Andrew Blitzer; Roger L Crumley; Seth H Dailey; Charles N Ford; Mary Kay Floeter; Allen D Hillel; Henry T Hoffmann; Christy L Ludlow; Albert Merati; Michael C Munin; Lawrence R Robinson; Clark Rosen; Keith G Saxon; Lucian Sulica; Susan L Thibeault; Ingo Titze; Peak Woo; Gayle E Woodson Journal: Otolaryngol Head Neck Surg Date: 2009-04-09 Impact factor: 3.497