Computerized Dynamic Posturography study of Parkinson's Disease Patients of Old Age

ABSTRACT

BACKGROUNDS Postural instability and vertigo arc not uncommon complaint from Parkinson`s disease (PD) patients. But little is known about the underlying cause of the symptoms. METHODS: Thirty-two patients with over 55 year of age, having Parkinson`s disease are studied with using a recently developed computerized dynamic posturography(CDP) and rotating chair testing(ROT) RESULTS: Vestibular dysfunction pat tent is found in 21 patients and improper use of vision was found in 10 patients. Delayed motor latency was noted in 5 patients. Saccadie dysmetria and prolonged saccadic reaction times were common features in all patients. 6 patients(18.8%) had absent responses in cold( 17degrees C) water caloric resting bilaterally and decreased responses in the lower frequencies(0.01~0.16 Hz) by ROT. Their vestibulo-ocular reflex could be suppressed during the ROT with visual fixation. MRI showed the presence of an infarction of the caudal cerebellum in one patient, the pons in another, and narrowed vertebral arteries in two patients. CONCLUSION: Relatively high incidence of vestibular dysfunction is associated with postural instability and increasing severity of symptoms. The main site of dysfunction in postural control is likely to be at a central motor level.