Photobiomodulation in Muscle Tension Dysphonia: A Pilot Study.

Area of Science:

• Otolaryngology
• Speech and Language Pathology
• Biomedical Engineering

Background:

• Muscle tension dysphonia (MTD) is a voice disorder characterized by increased muscle strain during phonation, often leading to vocal fatigue.
• Professional voice users are particularly susceptible to MTD and its associated symptoms.
• Photobiomodulation (PBM) is a non-invasive therapy using light to modulate cellular activity, with potential applications in tissue healing and inflammation reduction.

Purpose of the Study:

• To investigate the immediate and medium-term effects of photobiomodulation on vocal fatigue, acoustic, perceptual, and laryngeal parameters.
• To assess the efficacy of PBM as a standalone treatment for primary muscle tension dysphonia in professional voice users.

Main Methods:

• A pilot, longitudinal, prospective, randomized, comparative study was conducted with 15 professional voice users diagnosed with MTD.
• Participants were randomly assigned to a photobiomodulation (TG) or placebo (CG) group.
• Vocal fatigue (VFI), acoustic (AVQI), perceptual, and videolaryngostroboscopy assessments were performed at baseline, immediately post-intervention, and after four sessions.

Main Results:

• No statistically significant differences were found between the photobiomodulation and placebo groups for any outcome measures.
• No significant changes were observed over time within either group for the evaluated parameters.

Conclusions:

• Photobiomodulation, when applied alone with the studied parameters, did not demonstrate immediate or short-term efficacy in improving vocal fatigue or voice quality in professional voice users with MTD.
• The findings suggest that PBM may not be a sufficient standalone treatment for this population under the tested conditions.