Computing patient-specific hemodynamics in stented femoral artery models obtained from computed tomography using a...

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Fluid Dynamics

Background:

• In-stent restenosis is a common complication following endovascular treatment for peripheral artery disease.
• Understanding the relationship between abnormal hemodynamics and restenosis is crucial for improving patient outcomes.
• Patient-specific computational fluid dynamics (CFD) simulations offer a powerful tool for analyzing these hemodynamic factors.

Purpose of the Study:

• To develop and validate a robust 3D reconstruction method for patient-specific stented femoral artery models from CT images.
• To perform CFD simulations on these patient-specific models to analyze hemodynamic patterns.
• To investigate the influence of common femoral artery bifurcation and inlet velocity profiles on CFD results.

Main Methods:

• A semi-automatic segmentation algorithm was used to create 3D reconstructions from CT images, including artifact and thrombus removal.
• The reconstruction method was validated using 3D printed phantoms, comparing reconstructed geometries to CAD models.
• Patient-specific CFD models were generated, and simulations were conducted with varying bifurcation presence and inlet velocity profiles (flat vs. parabolic).

Main Results:

• The 3D reconstruction method demonstrated a mean error of approximately 6% when validated against 3D printed phantoms.
• CFD simulations showed similar helical flow structures across different scenarios (with/without bifurcation, flat/parabolic profiles).
• Wall shear stress in the stented region exhibited negligible differences (<0.5%) between the simulated scenarios.

Conclusions:

• A validated and robust method for creating patient-specific 3D models of stented diseased arteries from CT data has been established.
• CFD analysis using these models can provide insights into hemodynamics relevant to in-stent restenosis.
• The findings suggest that key hemodynamic features like helical flow are consistent across variations in bifurcation and inlet profiles within the stented region.