Prospective multi-institutional transnasal esophagoscopy: Predictors of a change in management.

OBJECTIVES/HYPOTHESIS: To evaluate clinical indications and endoscopic findings for patients undergoing transnasal esophagoscopy (TNE). STUDY DESIGN: Prospective, multi-institutional, observational cohort study at four tertiary centers. METHODS: Demographics, reflux finding score, reflux symptom index, Eating Assessment Tool (EAT-10) scores, clinical indications, and endoscopic findings were compared among patients whose TNE findings resulted in a changes in management (FCIM), defined as a referral, new medication, or surgery recommendation. RESULTS: Of the 329 patients who were enrolled nine (3%) were unable to complete the exam. In an adjusted regression model, male gender and elevated body mass index were significantly predictive of a positive TNE (P =.013-.045); 51% (n = 162/319) had TNE with FCIM. Common FCIM were esophageal stricture (7.5%), irregular Z-line (27.4%), reflux esophagitis (12.8%), and infectious esophagitis (6.3%) (P <.001-.010). Overall, the average EAT-10 was higher for patients with FCIM (9.7 vs. 5.4) than in those without it (P =.014). Patients with a history of head and neck cancer (HNCA) had FCIM 64% of the time, which rose to 81% if they had both HNCA and dysphagia. CONCLUSIONS: In treatment-seeking patients TNE is predictive of a change in management in males and obese patients. In patients with HNCA and dysphagia, TNE is likely to yield findings that cause a change in management. LEVEL OF EVIDENCE: 2b. Laryngoscope, 126:2667-2671, 2016.

Laryngeal Electromyographic findings in patients with vocal fold motion asymmetry.

OBJECTIVES/HYPOTHESIS: Vocal fold motion asymmetry (VFMA) is often attributed to vocal fold paresis or an anatomical variant. Although laryngeal electromyography (LEMG) may be used to evaluate patients with vocal fold paresis, electrodiagnostic findings in VFMA have not been well defined. STUDY DESIGN: Review of a case series METHODS: Twenty-five symptomatic patients with VFMA were examined by LEMG, and the findings were analyzed. RESULTS: Although all were thought to have unilateral recurrent laryngeal nerve paresis, LEMG showed only nine to have unilateral recurrent nerve paresis. There were nine with both ipsilateral recurrent laryngeal nerve and superior laryngeal nerve paresis, four with bilateral paresis, and three were normal. Reduced total number of units, reduced recruitment, motor units firing fast, and polyphasic units were more common, whereas fibrillation potentials, fasciculation, positive sharp waves, and complex repetitive discharges were uncommon. The LEMG findings are most consistent with old, healed neuropathy. McNemar's test for the acute versus chronic denervation potentials showed significant differences. CONCLUSIONS: VFMA has a high incidence of vocal fold paresis that can be better defined by LEMG. The site and side of paresis is often wrong based on laryngoscopy findings alone. The LEMG findings of VFMA appear to be consistent with old, healed neuropathy LEVEL OF EVIDENCE: 4 Laryngoscope, 126:E273-E277, 2016.

Interrater Reliability in Analysis of Laryngoscopic Features for Unilateral Vocal Fold Paresis.

OBJECTIVE: The diagnosis of paresis in patients with vocal fold motion impairment remains a challenge. In particular, laryngoscopy examination may result in significant disagreement in diagnosis among providers. We hypothesize that systematically evaluating for a standard set of clinical parameters will increase the diagnostic concordance among providers. STUDY DESIGN: Prospective case series conducted at a Tertiary referral Laryngology office. METHODS: Two laryngologists (rater 1) and two trainees (rater 2) rated laryngoscopy findings in 19 patients suspected of paresis. The diagnosis was confirmed with laryngeal electromyogram. A standard set of 27 ratings was used for each examination that included movement, laryngeal configuration, and stroboscopy signs. A kappa coefficient was calculated for agreement in laryngoscopy findings and effectiveness in predicting the laterality of paresis. RESULTS: A substantial agreement (kappa coefficient > 0.61) existed between the raters for vocal fold length, vocal fold thickness, bowing, and reduction in movement. A moderate agreement (kappa coefficient > 0.41) existed between raters for piriform opening and reduced kinesis. The senior author was accurately able to diagnose the side of paresis in 89.5% of cases for a kappa coefficient of 0.78, whereas the trainees correctly predicted the side of paresis in 63.1% for a kappa coefficient of 0.35. The raters agreed on the diagnosis in 73.7% of cases for a kappa coefficient of 0.50. CONCLUSIONS: Using a standard set of laryngoscopy findings may improve the provider's ability to identify the laterality of vocal fold paresis and increase interrater reliability compared with other series.

Differential expression of glial-derived neurotrophic factor in rat laryngeal muscles during reinnervation.

OBJECTIVES/HYPOTHESIS: Nonspecific, synkinetic reinnervation is one of the causes of poor functional recovery after a peripheral nerve lesion. Knowledge of the differential expression of neurotrophic factors that subserve axon guidance, as well as neuromuscular junction formation and maintenance in the denervated muscles, may allow appropriate interventions that will improve the functional nonsynkinetic reinnervation. STUDY DESIGN: Laboratory experiment. METHODS: The expression of glial-derived neurotrophic factor (GDNF) was studied in the abductor and adductor muscles of the larynx in the rat utilizing real-time polymerase chain reaction at different times following transection, anastomosis, and reinnervation of the right recurrent laryngeal nerve (RLN). Immunostaining of GDNF, axons, and the motor endplates were performed. This data was correlated with intramuscular mRNA GDNF expression. RESULTS: Significant upregulation of GDNF was observed until 14 days after RLN injury. The highest level of the GDNF expression was reached at different times in posterior cricoarytenoid (PCA), lateral thyroarytenoid (LTA), and medial thyroarytenoid (MTA). These expression peaks correlated with the timing of reinnervation observed on immunohistochemistry, where PCA was reinnervated first, followed by MTA and LTA. CONCLUSION: Differences of GDNF expression are linked to the differential timing of RLN axon regeneration and individual muscle reinnervation. The present finding suggests the need to further investigate the role of GDNF and other neurotrophic factors in the timing of reinnervation, axon guidance, and neuromuscular junction formation as it relates to synkinetic and nonsynkinetic RLN reinnervation. Future experimental results may provide insight to therapeutic options that could stimulate appropriate neuromuscular junction formation and nonsynkintic functional reinnervation following RLN injury.