Cinegraphic observations of laryngeal function in Parkinson's disease.

Thirty-two unselected male patients with Parkinson's disease were examined by telescopic cinelaryngoscopy. Correlation of vocal abnormality and general neurologic symptoms with the laryngoscopic examination leads to the conclusion that the phonatory abnormalities noted in Parkinson's disease are related to rigidity in the phonatory posture of the larynx. The described dysfunctions correlated with the symmetry of trunk and limb rigidity in 100% of the patients.