Analysis of cerebral blood flow by pneumatic-valves-controlled microfluidic device: risk assessment of infarction correlated with morphometric variation of cerebral vascular system

Abstract

Although cerebral blood flow is the crucial factor for cerebral infarction and the circle of Willis (CoW) is considered the primary control structure for cerebral hemodynamics, risk of cerebral infarction caused by the morphological variation in the CoW has never been studied due to lack of proper tools. Here, the alteration of cerebral blood flow in CoW variation was quantitatively assessed by a new analysis method using a microfluidic device that was controlled by pneumatic valves. Using this device, the occlusion of diverse major arteries was realized by closing the channel with pneumatic valves. The morphological variations of the CoW and their hemodynamics were designed and analyzed after occlusion of the major arteries. While the differences in hemodynamics of CoW variants were not statistically significant compared with a complete CoW without occlusion or with occlusion of the efferent arteries, the occlusion of afferent arteries such as common carotid artery and vertebral artery severely affected the flow rate (28.4–48.8 %) and related arterial pressure of efferent arteries (48.6 ± 6.7–36.0 ± 1.4 mmHg) in CoW variants where the posterior communicating artery and the P1 segment are absent, which is associated with cerebral ischemic infarction. The novel analysis system using microfluidics provides a robust and accurate method, in which the hemodynamics of individual morphological variation and stenosis, and occlusion of vessels can be analyzed. Thus, this method is particularly suitable for personalized analysis of hemodynamics and may find new applications in biomedical researches.