CPRI-based analysis of corresponding points (E8, I2) selective stimulation for cerebral blood flow balance

Abstract

This study represents the first attempt to verify the traditional medical concept of Ki Meridian (氣脈) using a quantitative index of cerebral hemodynamics. Employing the non-invasive cerebral blood flow measurement device Body-Mac System, the selective regulatory effects of stimulating the hand correspondence points E8 (carotid-artery correspondence) and I2 (vertebral-artery correspondence) on the balance between anterior and posterior cerebral circulation were analyzed. The Cerebrovascular Pressure Ratio Index (CPRI), calculated from the pressure ratio between the carotid and radial arteries, was used as the primary measurement parameter, and CPRI changes before and after +stimulation (Bo method) were compared in 30 healthy adults. The results revealed that, in Yin-type participants, E8 stimulation significantly increased anterior circulation (p < 0.01), whereas in Yang-type participants, I2 stimulation significantly increased posterior circulation (p < 0.01), with CPRI converging toward zero in both cases. No statistically significant change occurred with ipsilateral stimulation, demonstrating that selective cerebral blood flow regulation is induced only via stimulation of the complementary correspondence point. These findings align with the physiological mechanism of cerebral autoregulation and indicate that the traditional principle “實則瀉之, 虛則補之” (“reduce excess and tonify deficiency”) can be interpreted in the context of modern cerebrovascular physiology. This study is the first to quantitatively and in real time analyze selective redistribution of cerebral blood flow induced by correspondence-point stimulation and suggests future clinical and engineering applications for cognitive-function preservation, early prevention of dementia and stroke, and non- invasive cerebrovascular modulation interventions. Keywords: Cerebrovascular Pressure Ratio Index(CPRI), Selective Cerebral Blood Flow Regulation, Corresponding Point Stimulation (E8, I2), Anterior–Posterior Circulation Balance, Body-Mac System