Semi-automatic extraction of vascular networks in angiograms

A semi-automatic algorithm for the segmentation of angiographic images is proposed. First, the digital angiogram is smoothed by an image structure preserving technique which is based on homogeneity testing and anisotropic diffusion. Then, the watershed transform is applied to the smoothed image gradient magnitude and the resulting initial image partition is input to a fast hierarchical region merging process. Finally, the vessel regions are extracted from the segmented image by a simple point-and-click interactive procedure. Experimental results on Digital Subtracted Angiograms (DSA) are presented.