Computer modeling of different shaped patches in classical carotid endarterectomy

Abstract

Objective: to construct geometric models of carotid bifurcation and build a computer modeling for carotid endarterectomy (CEA) operations with patches of various configurations.Materials and methods. The method uses reconstructed models of a healthy blood vessel obtained from a preoperative computed tomography (CT) study of the affected blood vessel of a particular patient. Flow in the vessel is simulated by computational fluid dynamics using data from the patient's ultrasonic Doppler velocimetry and CT angiography. Risk factors are assessed by hemodynamic indices at the vessel wall associated with Wall Shear Stress (WSS).Results. We used the proposed method to study the hemodynamic results of 10 virtual CEA operations with patches of various shapes on a reconstructed healthy artery of a particular patient. The reason for patch implantation was to ensure that the vessel lumen is not narrowed as a result of the surgery, since closing the incision without a patch can reduce the vessel lumen circumference by 4–5 mm, which adversely affects blood flow. On the other hand, too wide a patch creates aneurysmorphic deformation of the internal carotid artery (ICA) mouth, which is not optimal due to formation of a large recirculation zone. In this case, it was found that the implanted patch width of about 3 mm provides an optimal hemodynamic outcome. Deviations from this median value, both upward and downward, impair hemodynamics. The absence of a patch gives the worst of the results considered.Conclusion: The proposed computer modeling technique is able to provide a personalized patch selection for classical CEA with low risk of restenosis in the long-term follow-up.

Keywords

• classical carotid endarterectomy
• computer modeling
• patch