title: Hemodynamics analyses in treated and untreated carotid arteries of the same patient: A preliminary study based on three patient cases.
abstract: Carotid atherosclerotic disease is highly related to cerebrovascular events. Carotid endarterectomy is the common operation method to treat this disease. In this study, hemodynamics analyses are performed on the carotid arteries in three patients, whose right carotid artery had been treated by carotid endarterectomy and the left carotid artery remained untreated. Flow and loading conditions are compared between these treated and untreated carotid arteries and evaluation of the operative results is discussed. Patient-specific models are reconstructed from MDCT data. Intraoperative ultrasound flow measurements are performed on the treated carotid arteries and the obtained data are used as the boundary conditions of the models and the validations of the computational results. Finite volume method is employed to solve the transport equations and the flow and loading conditions of the models are reported. The results indicate that: (i) in two of the three patients, the internal-to-external flow rate ratio in the untreated carotid artery is larger than that in the treated one, and the average overall flow split ratio by summing up the data of both the left and right carotid arteries is about 2.15; (ii) in the carotid bulb, high wall shear stress occurs at the bifurcation near the external carotid artery in all of the cases without hard plaques; (iii) the operated arteries present low time-averaged wall shear stress at the carotid bulb, especially for the treated arteries with patch technique, indicating the possibility of the recurrence of stenosis; (iv) high temporal gradient of wall shear stress (>35 Pa/s) is shown in the narrowing regions along the vessels; and (v) in the carotid arteries without serious stenosis, the maximum velocity magnitude during mid-diastole is 32~37% of that at systolic peak, however, in the carotid artery with 50% stenosis by hard plaques, this value is nearly doubled (64%). The computational work quantifies flow and loading distributions in the treated and untreated carotid arteries of the same patient, contributing to evaluation of the operative results and indicating the recurrent sites of potential atheromatous plaques.
authors.affiliation: Department of Biomedical Engineering, School of Life Science, Beijing Institute of Technology, Beijing, China.
authors.forename: Yuqian
authors.initials: Y
authors.lastname: Mei
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.|Department of Radiology, German Cancer Research Center (dkfz), Heidelberg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Müller-Eschner
authors.affiliation: Department of Biomedical Engineering, School of Life Science, Beijing Institute of Technology, Beijing, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yi
authors.affiliation: Department of Biomedical Engineering, School of Life Science, Beijing Institute of Technology, Beijing, China.
authors.forename: Zhaotong
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Biomedical Engineering, School of Life Science, Beijing Institute of Technology, Beijing, China.
authors.forename: Duanduan
authors.initials: D
authors.lastname: Chen
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Kronlage
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.|Institute of Diagnostic, Interventional and Pediatric Radiology, University Hospital Bern, Inselspital, Bern, Switzerland.
authors.forename: Hendrik
authors.initials: H
authors.lastname: von Tengg-Kobligk
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.affiliation: Department of Vascular and Endovascular Surgery, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Dittmar
authors.initials: D
authors.lastname: Böckler
authors.affiliation: Department of Vascular and Endovascular Surgery, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Serdar
authors.initials: S
authors.lastname: Demirel
mesh_terms: D001783:Blood Flow Velocity; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D003198:Computer Simulation; D016894:Endarterectomy, Carotid / Q000379:methods; D006801:Humans; D008955:Models, Cardiovascular; D066230:Patient-Specific Modeling; D016896:Treatment Outcome; D014463:Ultrasonography
keywords: Carotid artery; carotid endarterectomy; computational fluid dynamics; hemodynamics