Objective: This study aimed to assess the effects of surface electrical stimulation plus voice therapy on voice in dysphonic patients with idiopathic Parkinson's disease.
Method: Patients were assigned to 3 treatment groups (n = 28 per group) and received daily treatment for 3 weeks on 5 days a week. All three groups received voice therapy (usual care). In addition, two groups received surface electrical stimulation, either motor-level or sensory-level stimulation. A standardised measurement protocol to evaluate therapeutic effects included the Voice Handicap Index and videolaryngostroboscopy.
Results: Voice Handicap Index and videolaryngostroboscopic assessment showed statistically significant differences between baseline and post-treatment across all groups, without any post-treatment differences between the three groups.
Conclusion: Intensive voice therapy (usual care) improved idiopathic Parkinson's disease patients' self-assessment of voice impairment and the videolaryngostroboscopic outcome score. However, surface electrical stimulation used as an add-on to usual care did not improve idiopathic Parkinson's disease patients' self-assessment of voice impairment or the videolaryngostroboscopic outcome scores any further.
Keywords: Dysphonia; Parkinson's Disease; Transcutaneous Electric Nerve Stimulation; Voice Training.