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03/14/2008. Vasculature Modeling. Rohit Yengisetty Qusai Shikari. Laboratory for Product and Process Design (LPPD) Advisors: Andreas Linninger Anargyros Politis. Goal. Create an anatomically accurate model of the cerebral vasculature. Approach. Two ways
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03/14/2008 Vasculature Modeling • Rohit Yengisetty • Qusai Shikari Laboratory for Product and Process Design (LPPD) Advisors: Andreas Linninger Anargyros Politis
Goal • Create an anatomically accurate model of the cerebral vasculature
Approach Two ways • Use cerebral angiography images from the literature • Create vasculature using fractals
Cerebral Angiography Literature • Vasculature of the brain and cranial base: variations in clinical anatomy / Walter Grand, L.N. Hopkins; foreword by Axel Perneczky; illustrated by Paul H. Dressel; art design and photography by Paul H. Dressel and Walter Grand • Cerebral angio-CT / Kazuhiko Sadamoto, Keiji Fukui • Magnetic resonance angiography of the head and neck: a teaching file / Jeffrey S. Ross. • Angiography of cerebral circulation / Kurt Decker and Herbert Backmund. • Practical neuroangiography / P. Pearse Morris. • Atlas of the arteries of the human brain / Georges Salamon; avec la collaboration de J.M. Corbaz...[et al.] ; Préface du Doyen G. Lazorthes. • Arteries and veins of the human brain / Roger B. Stephens and Donald L. Stilwell. • Cerebral angiography / Krayenbühl/Yaşargil • Cerebral radionuclide angiography / Frank H. DeLand • 3D angiographic atlas of neurovascular anatomy and pathology / Neil M. Borden; with text contributions by, Jay K. Costantini; foreword by Robert F. SPetzler
Vascular Atlas Formation Using a Vessel-to-Image Affine Registration Method • Create Vasculature using distance maps (DM) & model-to-image registration method from MRI and CT images Dini Chillet, Julien Jomier, Derek Cool and Stephen Aylward
Distance Map (DM) - A DM is an image in which each voxel’s intensity corresponds to the distance to the nearest vessel ( Intensity α Distance to the nearest vessel) Distance Map Inverted Distance Map (IDM) Inverted Distance Map (IDM) - The intensity of the DM is inverted to get the Inverted Distance Map where the brightest pixels are near a vessel. (Intensity α 1/Distance to the nearest vessel)
Atlas Formation • Vascular Networks (Vi) • IDMi computed • IDMtemplate • Generate transformation parameter sets( Ti ) using vessel-to-image registration • Apply Ti to IDMi to transform them into the same coordinate system as IDMi Mean and Variance of IDMi’s form the Vasculature Atlas
Vessel-to-Image Registration - Affine Matrix (R) - Offset Vector (0) The goal is to find a maximal metric for which centerline points ( Xi ) map to the brightest pixels in the IDM
Monte Carlo Simulations 8 failed to converge on a solution 5 failed to converge on a solution
Z-value validation Arterio-venous malformation
Fractal Dimensions and Multifractility in Vascular BranchingM.Zamir Murray’s law for an arterial bifurcation Fractal Dimension (D) n is the number of branches s is the cross-sectional area of the branch