Evaluation of Cerebrovascular Reactivity in Normal and ?Atherosclerotic Subjects ; using Transcranial Doppler

J Korean Neurol Assoc > Volume 12(2); 1994 > Article

Journal of the Korean Neurological Association 1994;12(2): 237-244.

Transcranial Doppler를 이용한 정상군과 동맥경화군의 뇌혈관 반응성? 평가

홍근식, 노재규

서울대학교 신경과.

Evaluation of Cerebrovascular Reactivity in Normal and ?Atherosclerotic Subjects ; using Transcranial Doppler

Keun Sik Hong, M.D., Jae Kyu Roh, M.D.

Department of Neurology, College of Medicine, Seoul National University

Abstract

Background and Purpose : Cerebrovascular reactivity (CVR) can be estimated by measuring the change of cerebral blood flow that occurs during vasostimulation. To estimate the cerebrovascular reactivity, we investigated the change of flow velocity of the internal carotid artery (ICA) and the middle cerebral artery (MCA) during hyperventilation and hypoventilation with the transcranial doppler. So we studied whether the CVR measured by this method could show a significant difference between the normal and the atherosclerotic subjects and whether the CVR may decrease with age in normal gubjects. Methods : Using transcranial doppler, we measured the mean velocity (Vm), the pulsatility index (P.I.) at the resting state, the end of breath-holding and the end of hyperventilation in 30 normal and 10 atherosclerotic subjects, so we calculated the percentile change of mean velocity (% Vm) and P.I. (% P.I.) after the vasostimulation. We estimated the change of Vm, P.I., % Vm and % P.I. By the age group and compared those parameters between the age-matched normal control and atherosclerotic subjects. Results : The Vm in ICA and MI significantly decreased with age (p<0.01), but there was no significant difference in Vm and P. I. Between normal and atherosclerotic subjects. The % Vm and % P.I. In response to hyperventilation significantly decreased with age in ICA, M1, M2 and there was significant difference in % Vm of ICA and M1 after breath-holding and % Vm of ICA after hyperventilation between the normal and atherosclerotic subjects. Conclusion : The breath-holding and hyperventilation tests could be non-invasive and useful methods in estimation of the cerebrovascular reactivity and could be applied in the basal and follow-up evaluation of the cerebrovascular reserve of the ischemic stroke patients.