Three dimensional reconstruction of coronary artery stents from optical coherence tomography: experimental validation and clinical feasibility

Abstract

The structural morphology of coronary stents (e.g. stent expansion, lumen scaffolding, strut apposition, tissue protrusion, side branch jailing, strut fracture), and the local hemodynamic environment after stent deployment are key determinants of procedural success and subsequent clinical outcomes. High-resolution intracoronary imaging has the potential to enable the geometrically accurate three-dimensional (3D) reconstruction of coronary stents. The aim of this work was to present a novel algorithm for 3D stent reconstruction of coronary artery stents based on optical coherence tomography (OCT) and angiography, and test experimentally its accuracy, reproducibility, clinical feasibility, and ability to perform computational fluid dynamics (CFD) studies. Our method has the following steps: 3D lumen reconstruction based on OCT and angiography, stent strut segmentation in OCT images, packaging, rotation and straightening of the segmented struts, planar unrolling of the segmented struts, planar stent wireframe reconstruction, rolling back of the planar stent wireframe to the 3D reconstructed lumen, and final stent volume reconstruction. We tested the accuracy and reproducibility of our method in stented patient-specific silicone models using micro-computed tomography (μCT) and stereoscopy as references. The clinical feasibility and CFD studies were performed in clinically stented coronary bifurcations. The experimental and clinical studies showed that our algorithm (1) can reproduce the complex spatial stent configuration with high precision and reproducibility, (2) is feasible in 3D reconstructing stents deployed in bifurcations, and (3) enables CFD studies to assess the local hemodynamic environment within the stent. Notably, the high accuracy of our algorithm was consistent across different stent designs and diameters. Our method coupled with patient-specific CFD studies can lay the ground for optimization of stenting procedures, patient-specific computational stenting simulations, and research and development of new stent scaffolds and stenting techniques.

Patient-specific computational simulation of coronary artery bifurcation stenting

“…Qualitative ( a , b ), and quantitative ( c ) comparison of mean stent diameter (MSD) after computational stenting against OCT. The stents in ( b ) were 3D reconstructed from OCT 21 . Note that the computational stent simulation was blind to the final OCT results post-procedure.…”

“…The stents were 3D reconstructed from OCT and angiographic images using a custom-built Grasshopper Python code 21 . First, the stent struts were segmented as individual points and flattened to 2D surfaces.…”

“…The post-computational PCI bifurcation and stent geometries were used to discretize the fluid domain for CFD analyses (Fig. 1 ) 21 – 23 . The fluid domain was meshed with tetrahedral elements using ICEM CFD (ANSYS Inc.).…”

First-in-Human Computational Preprocedural Planning of Left Main Interventions Using a New Everolimus-Eluting Stent

“… We introduced 2 technical novelties with important clinical implications: 3D reconstruction of coronary artery bifurcation from the fusion of angiography with HD IVUS ( Figures 4A , 5A , and 6A ) and 3D stent reconstruction from HD IVUS ( Figure 4G ). 5 , 6 …”

“… 4 Initially, we 3D reconstructed patient-specific LM anatomies on the basis of angiography and HD IVUS ( Figures 4A, 4B , 5A, 5B , 6A, and 6B ). 3 , 4 , 5 , 6 The 3D reconstructed LM anatomies were meshed and assigned realistic plaque stiffness properties considering the longitudinal and circumferential plaque heterogeneity derived from HD IVUS ( Figures 4C , 5C , and 6C ). 3 , 4 After performing computational stent simulations and CFD analyses ( Figures 4D, 4E , 5D, 5E , 6D, and 6E , Videos 1 , 2 , and 3 ), we selected the optimal stent positioning, sizing (length, diameter, inflation pressures), and strategy for each individual patient ( Figure 7 ).…”