Construction of realistic branched, three-dimensional arteries suitable for computational modelling of flow

Abstract

Routinely performed biplane digital coronary angiograms were used to construct a three-dimensional model of the coronary arteries. The technique took the images and automatically picked the centreline and radii in each. By reading the information contained in the DICOM format, the rotation angle between the two images could be ascertained, and the centreline in three dimensions could be determined. Once the centreline and radii had been calculated, a finite volume mesh of the artery was constructed that could be used as input into a fluid dynamics package that solves Navier-Stokes equations. A four-section method was adopted for constructing the mesh, utilising three tubular segments and a small junction section. The tubes were constructed automatically, and the junction procedure was semi-automated, maximising user-control over this region. A structured mesh was used for the tubes, and an unstructured mesh was used to model accurately the irregular shape of the junction. The accuracy of the reconstruction method was established by projection of a mesh onto an independent image of the same artery and the use of a coronary phantom. These tests, along with calibration of the edge detection, established an error of less than 2% in the model.

Non-Newtonian blood flow in human right coronary arteries: steady state simulations

“…As described previously, (Corney et al, 2001;Johnston et al, 2004;Corney et al, 2004), coronary artery meshes were reconstructed from biplane angiograms, from which the centreline and radius of the artery along the centreline were extracted. The mesh was completed by creating a mesh of the entrance plane and extruding this mesh along the centreline, taking into account variations in radius.…”

“…These arteries have been described in detail previously , with arteries A, B and D representing normal arteries with diameters from 3 to 5 mm and artery C representing a so-called 'ectatic' artery with diameters from 5 to 7 mm. The arteries were recorded as biplane angiograms ( Figure 1 shows the angiograms for artery B as an example), and, using a previously published technique (Corney et al, 2001;Corney et al, 2004) based on centreline extraction and edge detection, the arteries were reconstructed in three dimensions resulting in a mesh suitable for computational fluid dynamics simulation. Figure 2 shows the variation in arterial radius (calculated as a geometric mean of the radii for each view) as a function of distance along the artery.…”

In vivo estimation of coronary mechanical wall deformation and its relation to plaque formation

“…A model of the right coronary artery is generated from a pair of non-coplanar angiogram images via a two-step process. Firstly, following the procedure developed in [9,10,11], three-dimensional coordinates of points along the artery midline are calculated in addition to estimates of the inner radii at these locations. The resulting data are used as input for a cubic spline interpolation routine written in Mathematica ¢ ¡ 4.1, to generate a model artery with elliptical cross-section.…”

A computational study on the biomechanical factors related to stent-graft models in the thoracic aorta

“…Medical and biological fluid problems investigated by employing computational fluid dynamics (CFD) tools receive intense attention in recent years [23][24][25]. CFD is considered to be an efficient and prevalent tool to obtain reliable flow field in a wide range of applications, especially the blood flow problems [18,19,[26][27][28][29]. Further investigations are needed to study the truly three-dimensional flow field in physiologically realistic geometries like the thoracic aorta in the human body.…”