title: Evaluation of aneurysm-associated wall shear stress related to morphological variations of circle of Willis using a microfluidic device.
abstract: Although microfluidic systems have been important tools in analytical chemistry, life sciences, and medical research, their application was rather limited for drug-screening and biosensors. Here, we described a microfluidic device consisting of a multilayer micro-channel system that represented the hemodynamic cerebral vascular system. We analyzed wall shear stresses related to aneurysm formation in the circle of Willis (CoW) and their morphological variations using this system. This device was controlled by pneumatic valves, which occluded various major arteries by closing the associated channels. The hemodynamic analysis indicated that higher degrees of shear stress occurred in an anterior communicating artery (ACoA), particularly in the hypoplastic region of the posterior communicating artery (PCoA) and the P1 segment. Furthermore, occlusion of a common carotid artery (CCA) or a middle cerebral artery (MCA) increased the shear stress, whereas occlusion of a vertebral artery (VA) decreased the shear stress. These results indicate that the morphological variation of the CoW may affect aneurysm formation resulting from increased wall shear stress. Therefore, the technique described in this paper provides a novel method to investigate the hemodynamics of complex cerebral vascular systems not accessible from previous clinical studies.
authors.affiliation: Department of Biomedical Engineering and Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea.
authors.forename: Seong-Won
authors.initials: SW
authors.lastname: Nam
authors.affiliation: Department of Biomedical Engineering and Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea.
authors.forename: Samjin
authors.initials: S
authors.lastname: Choi
authors.affiliation: Department of Biomedical Engineering and Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea.
authors.forename: Youjin
authors.initials: Y
authors.lastname: Cheong
authors.affiliation: Department of Obstetrics & Gynecology, The Catholic University of Korea, Kyonggi-do 480-717, Korea. Electronic address: yoni@catholic.ac.kr.
authors.forename: Yeon-Hee
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering and Healthcare Industry Research Institute, College of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea. Electronic address: sigmoidus@khu.ac.kr.
authors.forename: Hun-Kuk
authors.initials: HK
authors.lastname: Park
mesh_terms: D001696:Biomechanical Phenomena; D017536:Carotid Artery, Common / Q000503:physiopathology; D002941:Circle of Willis / Q000473:pathology* / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology* / Q000503:physiopathology*; D046210:Microfluidic Analytical Techniques; D020768:Middle Cerebral Artery / Q000503:physiopathology; D033081:Shear Strength; D013314:Stress, Mechanical
keywords: Aneurysm; Circle of Willis; Hemodynamics; Microfluidics; Shear stress