A 3D RECONSTRUCTION OF VASCULAR STRUCTURES FROM 2 X-RAY ANGIOGRAMS USING AN ADAPTED SIMULATED ANNEALING ALGORITHM

In this paper, a three-dimensional reconstruction of the vessel lumen from two angiographic views, based on the reconstruction of a series o f cross-sections is proposed. Assuming uniform mixing of contrast medi um and background subtraction, the cross-section of each vessel is rec onstructed through a binary representation. A priori information about both the slice to be reconstructed and the relationships between adja cent slices are incorporated to lessen ambiguities on the reconstructi on. Taking into account the knowledge of normal vessel geometry, an in itial solution of each slice is created using an elliptic model-based method. This initial solution is then deformed to be made consistent w ith projection data while being constrained into a connected realistic shape. For that purpose, properties on the expected optimal solution are described through a Markov Random Field. To find an optimal soluti on, a specific optimization algorithm based on simulated annealing is used. The method performs welt both on single vessels and on branching vessels possessing an additional inherent ambiguity when viewed at ob lique angles. Results on 2D slice independent reconstruction and 3D re construction of a stack of spatially continuous 2D slices are presente d for single vessels and bifurcations.