Current and Emerging Concepts in Muscle Tension Dysphonia: A 30-Month Review

Summary

The modern theory of hoarseness is that there are multifactorial etiologies contributing to the voice problem. The hypothesis of this study is that muscle tension dysphonia is multifactorial with various contributing etiologies. Methods: This project is a retrospective chart review of all patients seen in the Voice Speech and Language Service and Swallowing Center at our institution with a diagnosis of muscle tension (functional hypertensive) dysphonia over a 30-month period. A literature search and review is also performed regarding current and emerging concepts of muscle tension dysphonia. Results: One hundred fifty subjects were identified (60% female, 40% male, with a mean age of 42.3 years). Significant factors in patient history believed to contribute to abnormal voice production were gastroesophageal reflux in 49%, high stress levels in 18%, excessive amounts of voice use in 63%, and excessive loudness demands on voice use in 23%. Otolaryngologic evaluation was performed in 82% of patients, in whom lesions, significant vocal fold edema, or paralysis/paresis was identified in 52.3%. Speech pathology assessment revealed poor breath support, inappropriately low pitch, and visible cervical neck tension in the majority of patients. Inappropritate intensity was observed in 23.3% of patients. This set of multiple contributing factors is discussed in the context of current and emerging understanding of muscle tension dysphonia. Conclusions: Results confirm mutifactorial etiologies contributing to hoarseness in the patients identified with muscle tension dysphonia. An interdisciplinary approach to treating all contributing factors portends the best prognosis.

Introduction

Voice literature has long recognized functional dysphonia as an umbrella diagnosis for impairment of voice production in the absence of structural change or neurogenic disease of the larynx. Muscle tension dysphonia (MTD) semantically lies within the bounds of functional dysphonia, although it has only occasionally been investigated as a distinct entity in the spectrum of functional voice disorders, despite its widely accepted clinical presence. Early mention is made of voice disorders stemming from apparent increased laryngeal tension and poor habits of phonation,¹ and terms such as “myasthenia laryngis”² and “psychophonasthenia”³ have been suggested. Several authors have more recently proposed categorization schemes for the range of underlying behaviors in functional dysphonia, which include an MTD classification.4, 5, 6

Delineation of MTD from functional dysphonia has been suggested based on history, laryngoscopic, perceptual-acoustic, musculoskeletal, and psychological features.⁷ These data suggested that key features of MTD include posterior glottal chink, mucosal vocal cord changes, larynx rise, suprahyoid muscle tension, breathiness, glottal fry, glottal attack, and stridency.7, 8 Along with classification schemes, authors have suggested myriad titles for MTD in the literature (Table 1), suggesting various underlying etiologies and characteristics. This is curiously analogous to the modern theory of hoarseness, where there are multifactorial etiologies contributing to the voice problem. The hypothesis of this study is that muscle tension dysphonia is multifactorial with various contributing etiologies. Results of this retrospective chart review are put into the context of the present understanding of MTD with a thorough review of the literature.