Strain Elastosonography Measurement in Patients with Primary Muscle Tension Dysphonia Compared with Healthy Speakers: A Pilot Study.

ABSTRACT

OBJECTIVES: The purpose of this study was to investigate real-time elastosonography (RTE) to measure strain of the (para)laryngeal muscles in patients with primary muscle tension dysphonia (MTD) and healthy speakers. STUDY DESIGN: This is a cross-sectional study. METHODS: Ten patients with primary MTD (37.8 ± 10.53 years) and 10 healthy speakers (36.9 ± 9.8 years) participated. Participants were diagnosed as MTD patient or healthy via voice history, voice self-assessment, perceptual voice evaluation, laryngeal palpation, and videostroboscopy. Then, RTE was performed to extract strain index (SI) and strain ratio (SR) for all participants. The RTE was utilized for the suprahyoid, thyrohyoid, and the cricothyroid muscles, both in right and left sides during rest, /a/, and /i/ prolongations. To study the effect of group, task, and interactive effect on the SI and SR, two-way repeated-measures analysis of variance was performed. RESULTS: The effect of group on the SI was significant for the right cricothyroid (P ˂ 0.001). Significant effect of group on the SR obtained for the right suprahyoid, left thyrohyoid, and right cricothyroid (P < 0.05). Moreover, the only muscle whose SR was significantly affected by task was the left suprahyoid (P < 0.05). Compared to healthy speakers, the interactive effect was significantly lower in SI for the left cricothyroid, and higher in SR for both the right suprahyoid and left cricothyroid in patients (P < 0.05). CONCLUSIONS: The RTE can discriminate patients with primary MTD from healthy subjects in some laryngeal muscles, especially suprahyoid and cricothyroid. It may be regarded as a clinical instrument in the assessment of MTD in future. Further studies with bigger sample size are recommended.