Effects of Subthalamic Nucleus Deep Brain Stimulation on the Phonation and Articulation of the Patients with Parkinson's Disease

J Korean Neurol Assoc > Volume 22(5); 2004 > Article

Journal of the Korean Neurological Association 2004;22(5): 472-477.

시상하핵 뇌심부자극이 파킨슨병 환자들의 발성과 조음에 미치는 영향

성지은, 김향희† 김현숙 오승헌 홍지만 이명식

연세대학교 언어병리학 협동과정*, 연세대학교 의과대학 재활의학교실-언어병리학 협동과정†, 영동세브란스병원 신경과

Effects of Subthalamic Nucleus Deep Brain Stimulation on the Phonation and Articulation of the Patients with Parkinson's Disease

Jee Eun Sung

Graduate Program in Speech Pathology, Yonsei University*, Seoul; Department of Rehabilitation Medicine & Graduate Program in Speech Pathology†, Seoul; Department of Neurology, Yongdong Severance Hospital, Seoul, Korea

Abstract

Background: The purpose of this study was to investigate the effects of the subthalamic nucleus (STN) deep brain stimulation (DBS) on the phonation and articulation of patients with Parkinson's disease (PD).
Methods: Seven PD patients who underwent bilateral STN DBS were included. The patients were asked to make and sustain the vowel sounds /a/ and /i/ as long as possible and to repeat nonsense syllables, /pa/, /ta/, /ka/ and /pataka/ as quickly as possible for 3 seconds. When the patients were administered levodopa 'on' and 'off treatments, we evaluated the effect of DBS on the maximum phonation time (MPT), jitter (pitch perturbation), shimmer (intensity perturbation), tremor index and diadochokinetic rate (D아). In each condition, using a Unified Parkinson's Disease Rating Scale score, we also measured the motor disability of the patients.
Results: During levodopa ‘off’, both the DBS and levodopa treatment caused significant prolongation of the MPT of the vowels /a/ and /i/. Acoustic analysis showed that DBS had an effect on shimmer only when the patients were levodopa ‘off’. At the articulatory level, no significant changes were found in the diadochokinetic rate under any conditions. However, there was a correlation between the amount of improvement of voice tremor and sum of UPDRS scores measuring ‘tremor at rest’ and ‘postural tremor’.
Conclusions: In patients with advanced PD, STN DBS improves phonation, but had limited effects on articulation. Key Words: Parkinson's disease, Subthalamic nucleus stimulation, Phonation, Articulation.