Read Me for ".stl file of Circle of Willis Benchmark geometric model for hemodynamic simulation software" 
created by Dr. Alberto C. Figueroa 
published in the University of Michigan's Deep Blue Data repository on Oct 14, 2020

Description: This .stl file represents the largest vessels of the cerebral circulation, specifically around the Circle of Willis. The file was created from a Computed Tomography Angiography (CTA) of a relatively healthy patient. It consisted of a 512 x 512 x 709 voxel image with a resolution of 0:35 mm x 0:35 mm x 0:5 mm. The model includes the basilar artery (1), left and right internal carotid arteries (2, and 3), left and right anterior cerebral arteries (4, and 5), left and right middle cerebral arteries (6, and 7), left and right posterior cerebral arteries (8, and 9), and various communicating arteries (10, 11, and 12). 

Methodology: The .stl file of the main arteries in the Circle of Willis was created from Computed Tomography Angiography (CTA) data using a segmentation procedure whereby the arterial lumen boundary was defined using a combination of manual demarcation, image thresholding, and level-set segmentation [1,2]. A set of vessel centerline paths and 2-D segmentations along each path were produced; from these a 3-D geometric solid model defined by non-uniform rational B-splines (NURBS) was created. 

[1] N. Wilson, K. Wang, R. Dutton, C.A. Taylor, "A software framework for creating patient specific geometric models from medical imaging data for simulation based medical planning of vascular surgery", Medical Image Computing and Computer-Assisted Intervention MICCAI 2001, Springer, 2001, pp. 449–456. doi: 10.1007/3-540-45468-3_54 [2] N. Xiao, J.D. Humphrey, C.A. Figueroa, "Multi-Scale Computational Model of Three-Dimensional Hemodynamics within a Deformable Full-Body Arterial Network”, Journal of Computational Physics, 2013, Vol 244, pp. 22-40. doi: 10.1016/j.jcp.2012.09.016

Please cite this data set as:
Figueroa, C. (2020).stl file of Circle of Willis Benchmark geometric model for hemodynamic simulation software [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/xx1r-zg70