Table II.

Registration results of range scan data to CT data (organ phantom) and physical space data (calibration phantom). Target set (a) represents a nylon screw head on the liver’s surface. Target set (b) refers to the peripheral Teflon spheres that were used as fiducials in the point-based registration but were not used in the surface registration. Target set (c) are points on the calibration phantom not used as fiducials. For each of the 12 trials, there were 126 unique combinations of five fiducials and four targets.

Phantom	Scaling	Registration method	FRE (points)/ Residual (surface), mm	TRE, mm
Organ	Rigid	Point	2.2±1.3 (6.0) n=119	(a) 1.7±0.5 (2.5) n=11
Organ	Similarity	Point	1.1±0.8 (3.5) n=119	(a) 1.8±0.5 (2.7) n=11
Organ	Rigid	Surface	0.75±0.07 (0.83) n=6	(a) 2.0±0.6 (2.7) n=6 (b) 4.1±1.7 (8.1) n=42
Organ	Similarity	Surface	0.65±0.04 (0.70) n=6	(a) 2.4±0.5 (3.0) n=6 (b) 3.6±1.7 (7.2) n=42
Calibration phantom	Rigid	Point	1.0±0.6 (3.8) n=7560	(c) 1.4±0.7 (4.8) n=6048