Objective: In this case report, we aimed to examine the effects of an intensive voice treatment (the Lee Silverman Voice Treatment [LSVT®LOUD]) for Wilson's disease (WD), and adult cerebral palsy (CP), and dysarthria.Method: The participants received LSVT®LOUD four times a week for 4 weeks. Acoustic, perceptual (GRBAS) analyses were performed and data from the Voice Handicap Index (VHI) were obtained before and after treatment.Results: Besides the Harmonics-to Noise Ratio (HNR) value (dB) of the participant with WD, for both participants' fundamental frequencies (Hz), jitter (%), and shimmer (%) values showed significant differences (p < .05) after therapy. Both participants showed significant improvements (p < .05) in the duration (s) and the sound pressure level (dB, SPL) of sustained vowel phonation (/a/), in SPL (dB) of pitch range (high and low /a/) and reading and conversation (p < .01). There was a positive improvement in the high-frequency values (Hz) of both participants but not in the low-frequency values (Hz) in the participant with WD. Perceptual analysis with GRBAS judgements of sustained vowel (/a/) and paragraph reading of two participants also showed improvement. After therapy, perceived loudness of the participants' voice increased.Conclusions: The findings provide some preliminary observations that the individuals with WD and the adult individuals with CP can respond positively to intensive speech treatment such as LSVT®LOUD. Further studies are needed to investigate speech treatments specific to WD and adult CP.
Keywords: LSVT-LOUD; Wilson’s disease; adult Cerebral Palsy; dysarthria.