[Treatment of vocal symptoms in Parkinson's disease: the Lee Silverman method]

Mild changes in voice quality and articulation of speech may be seen in early phases of Parkinson's disease (PD). Voice and speech disturbances in PD constitute a hypocinetic dysarthria or dysarthrophonia and are characterized by monotony and reduced intensity of voice, imprecise articulation and disturbances of rhythm. Favorable results with an intensive method (Lee Silverman Voice Treatment) for the treatment of voice disturbances in PD were recently reported. The main goal of the method is to augment vocal intensity through the increment of phonatory effort. The purpose of the present study was to characterize vocal abnormalities (hoarseness, breathiness, articulatory pattern and inteligibility) in a group of patients with PD and to evaluate the therapeutic efficacy of the Lee Silverman method. Acoustic as well as perceptive-auditory analysis showed statistically significant differences between pre and post treatment groups. Although the articulatory pattern has not considerably changed, the benefits obtained with the improvement in vocal quality positively influenced overall quality of oral communication.