Table 5.

General comparison with previously published works for the detection of AC and PC points. These are the results reported on the datasets used in the source papers. Note that all the other methods required some prior information either by finding the landmarks in the mid-sagittal plane only, or using spatial priors and region of interest. While the proposed method does not require any prior information, and it is also applied to the largest dataset.

Method	Mean Error (mm)		Data Size	Priors
	AC	PC
Verard et al. (1997)	0.41 ± 0.21	0.35 ± 0.32	30	Mid-sagittal plane
Prakash et al. (2006) - expert I	1.20 ± 1.30	1.10 ± 1.30	71	Mid-sagittal plane
Prakash et al. (2006) - expert II	1.20 ± 1.00	1.10 ± 1.20	71	Mid-sagittal plane
Ardekani & Bachman (2009) - NKI	0.90 ± 1.60	0.90 ± 1.80	48	Initialisation point
Ardekani & Bachman (2009) - IXI	1.10 ± 2.20	0.90 ± 1.80	84	Initialisation point
Guerrero et al. (2011)	0.45 ± 0.22	0.46 ± 0.20	200	Spatial prior probabilities
Guerrero et al. (2012)	0.67 ± 0.59	0.64±0.31	200	Spatial prior probabilities
Liu & Dawant (2015)	0.55 ± 0.30	0.56 ± 0.28	100	Region of interest
Proposed RL Agents	1.86 ± 1.07	2.01 ± 1.29	832	-