Table 2.
Commonly used notations.
| Symbols | Description |
|---|---|
|
| |
| I(x) | CT image |
| x | 3D coordinates |
| k | Organ index |
| Ak | Set of shape–location and intensity priors of organ k |
| Pk(x) | Probabilistic atlas (PA) of organ k |
| sk(b) | Statistical shape model (SSM) of organ k |
| Hk(I) | Intensity model (IM) of organ k |
| HOk(I) | Normalized histogram of organ k |
| HBk(I) | Normalized histogram of background of organ k |
| b | Shape parameter vector |
| S eg(·) | Segmentation operation |
| s0 | Surface shape vector (concatenation of 3D coordinates) of target organ |
| sk | Surface shape vector of predictor organ k |
| s̃i | Predictor vectors (set of surface shape vectors of predictor organs) of case i |
| Tp | Training datasets of predictor organs for partial least squares regression (PLSR) |
| Tt | Training datasets of target organ for PLSR |
| PLSR(s̃; Tp, Tt) | PLSR model |
| ri | Residual of case i after PLSR prediction, which is the difference between predicted and true shapes |