Correlation of self-assessment with expert rating and acoustic analysis for spasmodic dysphonia treatment with botulinum neurotoxin A

ObjectivesObjective and subjective evaluation of botulinum neurotoxin A (BoNTA) treatment for adductor type spasmodic dysphonia is presented. Therefore, a combinatorial approach based on patients’ and speech experts’ assessment of voice impairment, as well as on the acoustic analysis of spoken standardized text was performed.Study designProspective clinical study.Materials and methodsFor 17 patients, the voice quality prior to and 4–8 weeks after BoNTA injection (9 transoral, 8 transcutaneous) was investigated. Voice Handicap Index-12 (VHI-12) questionnaires as well as ratings of the GRB (grade, roughness, breathiness) scale were analyzed. Moreover, objective parameters such as pure speech duration, local jitter, local shimmer and voice breaks were evaluated.ResultsThe pre-post analysis of all patients revealed a significant reduction of the VHI-12 score, the jitter values and the number of voice breaks. Changes in speech duration and breathiness differed significantly for transoral vs. transcutaneous BoNTA injection.ConclusionsWe were able to correlate the questionnaire-based self-assessment with external evaluation of the speech roughness and with acoustic signal analysis parameters, in particular for the jitter. Our data indicated beneficial effects for transoral BoNTA application.