Objective measurement of muscle tension in the throat in individuals with muscle tension dysphonia

This is a two-phase study. Phase 1 - 25 participants (20 with MTD, 5 controls) will be recruited. They will be required to attend a single data collection session that will take up to one hour. All participants will undergo the following: 1) voice assessment (approx. 3 minutes long; sustained production of vowel sound "ee", repetition of the sentence "how hard did he hit him?", and humming), audio will be recorded using a microphone attached to clothing; 2) assessment using flexible endoscopic imaging inserted through the nose and into the throat, including a repeated voice assessment (approx. 5 minutes long; sustained production of vowel sound "ee", repetition of the sentence "how hard did he hit him?", and humming) with endoscope in situ; 3) high-resolution surface electromyography (sEMG; placed on the skin overlaying the neck, approx. 10 minutes to fit) will then be used during a further repetition of the voice assessment (approx. 3 minutes long; sustained production of vowel sound "ee", repetition of the sentence "how hard did he hit him?", and humming); 4) flexible endoscope will be re-placed into the throat (simultaneously with sEMG) and a final voice assessment will be completed (approx. 5 minutes long; sustained production of vowel sound "ee", repetition of the sentence "how hard did he hit him?", and humming). The assessment will be run by a Speech-Language Therapist/PhD student. Phase 2 5 Speech-Language Therapists (SLT) will be provided with de-identified still images and video files gathered during Phase 1 of the study. The SLTs will use two different methods (subjective and objective software) to measure the amount of muscle tension in the laryngeal muscles. The software is newly developed by members of the research team, and is as yet un-named. The SLTs will use the software to gather objective measurements by measuring number of pixels in endoscopic still images and videos. To do this, the SLTs will measure vocal fold length and width (at anterior 1/3 and halfway point of the vocal folds), which the software will use to calculate total pixel value. Total pixel value will quantify visible vocal fold as an indicator of muscle tension. To determine subjective measures, the SLTs will rate constriction using a scale (0 - no constriction, 1 - mild constriction, 2 - mild-moderate constriction, 3 - moderate constriction, 4 - moderate-severe constriction, 5 - severe constriction, 6 - complete constriction/no visibility of the vocal folds). Participation in this phase of the study will take up to four hours in total. This does not need to be completed in one go, but will need to be completed within one week.