Biomedical Engineering Reference
In-Depth Information
(a)
(b)
(c)
(d)
Figure 13.
Images showing tracking of (a,b) endocardial boundary using the active contour
model and (c,d) the mitral valve leaflet boundary. Reprinted with permission from [28].
Copyright c
1998, IEEE.
segmentation problem, one of the major challenges lies in the occurrence of fuzzy
boundaries, as previously mentioned. Thus, transition from one region to another
remains occluded by a lack of strong edges. Visually the transition can be observed
by a change in other features and from the global information. Thus, where local
statistics proved to have limitations in making a clear distinction between two
regions, utilization of global statistics within the snake framework was found to
be helpful.
3.3. Regional Information
Deformable models attracted the attention of the medical image analysis com-
munity for its ability to conform to the same framework constraints for a geometric
shape and image information. In particular, after the introduction of regional en-
ergy that controls the propagation term, this model became more popular. The
