A Correlativity Study Between Hemodynamic And Carotid Atherosclerotic Stenosis

Objective: In clinical,we could find that most of the carotid stenosis develops in initial period of internal carotid artery in carotid sinus,Here is remind that the occurrence of carotid atherosclerotic stenosis may be caused by blood flow dynamics characteristic parameters.To reconstruct the stenotic carotid artery to the normal structure by using the software,we investigate hemodynamic factors which are associated with carotid atherosclerotic stenosis.Our study might provide an new adjuvant treatment to improve outcomes of patients with carotid atherosclerotic stenosisMethods: We retrospectively recruited 9 patients with unilateral carotid artery stenosis who were admitted to the First Affiliated Hospital of Dalian Medical University for the head and neck cerebral CTA examination from May 2016 to August 2017.l,The original CTA images were imported into the Mimics 15.0 software to reconstruct the normal carotid arteries.And then we reconstructed three-dimensional(3D)model of the stenosed carotid artery according to the two-dimensional(2D)structure of narrowed vessel wall.The reconstructed 3D model was imported into Geomagic 2014 Reverse Engineering software for precise digital optimization processing,and then in the 3-matic 7.0 software for smoothing,and finally in hemodynamics software ICEM CFD 16.0 for finite element gridding.The boundary conditions were set up to fit the human blood flow.The relevant hemodynamic parameters of the model were measured and analyzed by ANSYS CFX 16.0 software.Results: Our results showed starting period of the contralateral internal carotid artery wall systolic WSS was 0.56 ±0.38 Pa,rehabilitation period of internal carotid artery stenosis after wall systolic WSS in the diseased side was 0.22± 0.16 Pa,p < 0.01,systolic WSS in health side is significantly higher than that in diseased side after recovery.The contralateral internal carotid artery section wall late diastolic WSS was 0.06 ± 0.04 Pa,internal carotid artery stenosis of diseased side in the period of recovery after the lateral end-diastolic WSS was 0.03± 0.02 Pa,p < 0.01,end-diastolic of the contralateral WSS than with diseased side after his recovery,with statistical significance.In addition,the initial period of internal carotid artery wall(i.e.,atherosclerotic plaque location),narrow the OSI values rehabilitation group was obviously higher than that of the contralateral group,narrow side wall OSI was 0.20 ± 0.03,the contralateral carotid artery wall OSI was 0.31± 0.10,p < 0.01).In the systolic phase,the external wall pressure gradient in the contralateral group was 26250.32 ±35486.91 units,internal carotid artery systolic stenosis group starting period of external wall pressure gradient was 3724.22± 2635.17 units,p = 0.076,diastolic health side wall pressure gradient was 647.04 ± 877.36 units,diastolic phase of the internal carotid artery stenosis group starting period of external wall pressure gradient was 253.28 ±186.55,p = 0.136,no statistical significance.Conclusion: It is feasible to reconstruct stenotic carotid artery and simulate hydrodynamics conditions by using computer image processing software.s.Lower WSS and higher OSI may be the risk factors for arterial stenosis of external wall of carotid bifurcation.