3D reconstruction techniques of human coronary bifurcations for shear stress computations.
BACKGROUND
Heterogeneity in plaque composition in human coronary artery bifurcations is associated with blood flow induced shear stress. Shear stress is generally determined by combing 3D lumen data and computational fluid dynamics (CFD). We investigated two new procedures to generate 3D lumen reconstructions of coronary artery bifurcations for shear stress computations.


METHODS
We imaged 10 patients with multislice computer tomography (MSCT) and intravascular ultrasound (IVUS). The 3D reconstruction of the main branch was based on the fusion of MSCT and IVUS. The proximal part of side branch was reconstructed using IVUS data or MSCT data, resulting in two different reconstructions of the bifurcation region. The distal part of the side branch was based on MSCT data alone. The reconstructed lumen was combined with CFD to determine the shear stress. Low and high shear stress regions were defined and shear stress patterns in the bifurcation regions were investigated.


RESULTS
The 3D coronary bifurcations were successfully generated with both reconstruction procedures. The geometrical features of the bifurcation region for the two reconstruction procedures did not reveal appreciable differences. The shear stress maps showed a qualitative agreement, and the low and high shear stress regions were similar in size and average shear stress values were identical. The low and high shear stress regions showed an overlap of approximately 75%.


CONCLUSIONS
Reconstruction of the side branch with MSCT data alone is an adequate technique to study shear stress and wall thickness in the bifurcation region. The reconstruction procedure can be applied to further investigate the effect of shear stress on atherosclerosis in coronary bifurcations.
Biomedical Engineering, Department of Cardiology, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, The Netherlands. Electronic address: f.gijsen@erasmusmc.nl.
Frank J H
FJ
Gijsen
Biomedical Engineering, Department of Cardiology, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Johan C H
JC
Schuurbiers
Biomedical Engineering, Department of Cardiology, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Alina G
AG
van de Giessen
Biomedical Imaging Group, BIGR, Department of Radiology and Medical Informatics, Erasmus MC, PO Box 2040, 300CA, Rotterdam, The Netherlands.
Michiel
M
Schaap
Biomedical Engineering, Department of Cardiology, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Anton F W
AF
van der Steen
Biomedical Engineering, Department of Cardiology, Erasmus MC, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Jolanda J
JJ
Wentzel
D003331:Coronary Vessels / Q000033:anatomy & histology* / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008953:Models, Anatomic; D058226:Plaque, Atherosclerotic / Q000503:physiopathology*; D033081:Shear Strength; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed / Q000379:methods*; D018084:Ultrasonography, Interventional
3D reconstruction; Bifurcation; Coronary artery; Shear stress