1. A method of segmenting an anatomic entity in a digital medical image, the method comprising the steps of: defining, for each of a number of landmark points in the digital medical image, an initial position of each of the landmark points; connecting a plurality of pairs of the landmark points to each other to form polygons defining a mesh; constructing a rectangular grid around each of the landmark points in the mesh; sampling a neighborhood in each rectangular grid around the initial position for each of the connected landmark points in the mesh, the neighborhood including a number of candidate locations of the connected landmark points in the mesh; calculating a graph data structure for all of the connected landmark points in the mesh, each node (vertex) of the graph data structure representing a connected landmark point of the connected landmark points in the mesh and each edge (arc) of the graph data structure representing the connection between a pair of the landmark points in the mesh; calculating a path through the graph data structure wherein an order of visiting the connected landmark points in the mesh is determined by the path through the graph data structure, the path being a minimum spanning tree; optimizing a cost function expressing a weighted sum of an overall gray level cost and an overall shape cost for all of the candidate locations of the connected landmark points in the mesh based on the path; and calculating a segmented anatomic entity as a surface or a volume through a selected combination of the candidate locations of each of the connected landmark points in the mesh for which combination the cost function is optimized.