5. An apparatus for Ileo-Cecal Valve (ICV) detection in an input 3D computed tomography (CT) volume, comprising: means for detecting initial box candidates for the ICV based on an ICV orifice in said input 3D CT volume; and means for detecting a box bounding the ICV in said 3D CT volume by sequentially detecting possible locations, scales, and orientations of the box bounding the ICV using incremental parameter learning based on said initial box candidates.
6. The apparatus of claim 5 , wherein said means for detecting initial box candidates for the ICV comprises: means for detecting a number of ICV orifice candidate voxels in said 3D CT volume using a trained 3D point detector; means for aligning an orientation of a 3D box centered at each orifice candidate voxel with a gradient vector at that orifice candidate voxel, wherein a scale of each 3D box is fixed; means for generating a set testing boxes by rotating the orientation of the 3D box centered at each orifice candidate voxel; and means for detecting a number of said testing boxes as initial box candidates using a trained 3D box detector.