Multi-step vessel segmentation and analysis is provided. In various embodiments, a branch detection algorithm is applied to a medical image to determine a plurality of branches of a blood vessel appearing in the medical image. A plurality of segments of the blood vessel appearing in the medical image is determined. Each of the plurality of segments is bounded by one of the plurality of branches. An edge detection algorithm is applied piecewise to each of the plurality of segments. A composite blood vessel outline is formed from the piecewise edge detection.
