Table 2.

Correlation coefficients of three organs and lung reference for four segmentation methods

Segmentation methods	Liver–lung reference	Stomach–lung reference	Pancreas–lung reference
Integrated edge detection and region growth	0.8981	0.9250	0.8119
Level set	0.8389	0.9350	0.9218
Hybrid gradient, region growth and shape constraint	0.9163	0.9261	0.8906
Manual contour	0.9379	0.9201	0.9372