Evaluation of Deformable Image Registration for Three-Dimensional Temporal Subtraction of Chest Computed Tomography Images

Table 1

The root-mean-square error of fiducial registration with regard to the 3D average distance and the average displacement of landmark feature points in the following three directions before DIR in the 10 cases: right-left (RL), anterior-posterior (AP), and superior-inferior (SI).

Cases	1	2	3	4	5	6	7	8	9	10	Avg.
3D RMS (mm)	19.06	5.04	6.35	4.95	92.02	25.67	5.43	17.16	8.43	24.04	20.82
RL (mm)	4.57	10.62	23.17	−13.31	42.36	3.93	17.77	−54.79	−48.07	20.04	0.63
AP (mm)	1.16	−4.81	5.33	−8.95	−34.68	5.22	0.66	−42.54	−20.41	10.92	−8.81
SI (mm)	3.01	3.55	20.85	−17.72	6.52	−14.91	16.92	−9.52	42.26	−11.18	3.98