Fully parallelized Lattice Boltzmann scheme for fast extraction of biomedical geometry

Abstract

We develop a fully parallel numerical method which quickly performs 2D and 3D segmentation on GPU to extract anatomical structures from medical images. The algorithm solves the level set equations completely within a Lattice Boltzmann model (LBM). Compared with existing LBM-based segmentation approaches, a parallel distance field regularization is added to the LBM computing scheme to keep computation stable with large time step iteration. This approach also avoids external regularization which has been a major impediment to direct parallelization of level set evolution with LBM. It allows the whole computing process to be efficiently executed on GPU. Moreover, the method can be incorporated with different image features to adopt in various image segmentation tasks. Therefore, our method enables fully GPU accelerated geometric extraction from medical images, leading to high computing performance which is demanded in many practical applications. This method is used to exact accurate 2D and 3D anatomical structures from many real world CT and MRI images. The achieved results can also directly feed required boundary information to LBM-based hemodynamics simulation.

Volumetric lattice Boltzmann method for wall stresses of image-based pulsatile flows

“…1 . Since we have developed a method to do image segmentation from DICOM format and calculate the volumetric parameter and the normal direction vector of each boundary cell 29 , 49 , the STL format is not necessary. We segmented the left carotid (with a bifurcation) and vertebral (tube-like) arteries, shown in Fig.…”

“…Such a task is usually case to case with a lot of uncertainties, related to the imaging modality, machine resolution, scanning skills, disease conditions, etc. Although we have developed techniques for DICOM image segmentation 30 , 49 , 50 , we strongly recommend having rigorous image segmentation with expertise, instead of simply running software with extensive manual inputs, as it will affect the quantification of the hemodynamics. All the modern CAD (Computer-Aided Design) software packages such as SolidWorks export their native file format into STL format.…”