Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative diseases, usually in elderly. The clinical manifestations are resting tremor, bradykinesia, decreased muscle strength, rigidity, postural and gait abnormalities, and disturbances in voice, speech and swallowing. Swallowing disorders lead to dehydration and malnutrition, and increased occurrence of aspiration pneumonia. T…