Laryngeal and Vocal Tract Strategies to Reduce Vocal Fold Contact Pressure

This study will investigate the degree to which a well-documented voice therapy technique, resonant voice therapy, reduces vocal fold contact pressure compared to baseline, and which if any laryngeal and vocal tract adjustments occur in association with this phonation pattern. The investigators will measure contact pressure in vivo in human subjects, and will use computed tomography scans to assess laryngeal and vocal tract configurations before and after initial voice training, in adults with phonotraumatic lesions. The investigators will correlate these measures to patient-reported outcome measures and other secondary outcome measures across longer-term therapy. It is hypothesized that findings regarding favorable physical adjustments associated with reduction in contact pressure shown in this aim will match those identified in our recent simulation studies, and that initial reduction in contact pressure in resonant voice, associated with relevant perceptual, acoustic, and subglottic pressure changes, will correlate with improved long-term voice therapy outcome.

Patients will be those who have been diagnosed by a fellowship trained laryngologist with bilateral mid-membranous lesions that by appearance and history are phonotraumatic and who are referred to resonant voice therapy (RVT). Each subject will receive resonant voice therapy, a standard of care procedure for treating phonotraumatic vocal hyperfunction. The full standardized voice therapy program will have a duration of four weeks, each week with one 60-minute therapy session. All voice therapy sessions will be video recorded. Ten percent of recordings will be randomly selected and used in fidelity checks. Data collection will take place at 3 time points: before therapy (baseline), immediately after an initial therapy session, and after 4 weeks of therapy. At baseline, each subject will fill out a Voice Handicap Index-10 (VHI-10) questionnaire, and will receive videoendoscopic examination, CT scans of the head and neck region during phonation, acoustic and subglottal pressure measurement, and contact pressure measurement. Data collection will be repeated the same day following an initial session of RVT training. Same-day data collection will ensure that lesion characteristics have not changed from baseline, and avoid confounding effects of lesion change in contact pressure measures. Degree of resonant voice acquisition will be determined by speech language pathologists (SLPs) real-time and will be further characterized quantitatively by post hoc perceptual evaluation and acoustic measures. Finally, after 4 weeks of RVT, follow-up measure will include VHI-10, endoscopic exam, perceptual, acoustic, and subglottal pressure measurement.

Inclusion criteria

• Ages 18-40 years (to minimize developmental changes associated with adolescent and elderly age)
• Clinic diagnosis by a fellowship trained laryngologist of mid-membranous lesions that by history and appearance are phonotraumatic
• Must be referred for voice therapy

Exclusion criteria

• Medical comorbidities (e.g., autoimmune disorders) beyond seasonal allergy and laryngopharyngeal reflux
• Vocal fold lesions generally regarded to be less responsive to voice therapy (e.g. vocal fold cysts).
• Claustrophobia
• Inability to replicate fundamental frequencies required for the study at the intensity levels determined