Table 3.

The number and the proportion of patients who met the criteria

Criteria	Direction	Number of patients at risk	Whole RT-CT slices	RT-CT slices at superior segment	RT-CT slices at middle segment	RT-CT slices at inferior segment
			36 (25–54) slices	12 (8–18) slices	13 (9–18) slices	12 (8–18) slices
1 or more RT-CT slices	Anterior (+)	155	61 (39.4%)	41 (26.5%)	19 (12.3%)	24 (15.5%)
	Posterior (−)	155	5 (3.2%)	4 (2.6%)	4 (2.6%)	2 (1.3%)
	Left (+)	155	15 (10.3%)	12 (7.7%)	1 (0.6%)	3 (1.9%)
	Right (−)	155	16 (9.7%)	15 (9.7%)	3 (1.9%)	1 (0.6%)
	2D distance	155	84 (54.2%)	65 (41.9%)	40 (25.8%)	38 (24.5%)
10% or more RT-CT slices	Anterior (+)	155	51 (32.9%)	39 (25.2%)	17 (11.0%)	22 (14.2%)
	Posterior (−)	155	4 (2.6%)	4 (2.6%)	3 (1.9%)	1 (0.6%)
	Left (+)	155	11 (7.1%)	11 (7.1%)	1 (0.6%)	3 (1.9%)
	Right (−)	155	7 (4.5%)	11 (7.1%)	2 (1.3%)	1 (0.6%)
	2D distance	155	77 (49.7%)	62 (40.0%)	37 (23.9%)	34 (21.9%)
20% or more RT-CT slices	Anterior (+)	155	36 (23.2%)	38 (24.5%)	14 (9.0%)	18 (11.6%)
	Posterior (−)	155	4 (2.6%)	4 (2.6%)	3 (1.9%)	1 (0.6%)
	Left (+)	155	7 (4.5%)	8 (5.2%)	1 (0.6%)	2 (1.3%)
	Right (−)	155	5 (3.2%)	10 (6.5%)	2 (1.3%)	1 (0.6%)
	2D distance	155	56 (36.1%)	61 (39.4%)	31 (20.0%)	29 (18.7%)
50% or more RT-CT slices	Anterior (+)	155	9 (5.8%)	27 (17.4%)	9 (5.8%)	12 (7.7%)
	Posterior (−)	155	1 (0.6%)	4 (2.6%)	1 (0.6%)	1 (0.6%)
	Left (+)	155	0 (0.0%)	4 (2.6%)	1 (0.6%)	1 (0.6%)
	Right (−)	155	1 (0.6%)	9 (5.8%)	0 (0.0%)	1 (0.6%)
	2D distance	155	20 (12.9%)	51 (32.9%)	18 (11.6%)	22 (14.2%)

The criteria were the number and the ratio of RT-CT slices in each patient which showed the calculated coordinate of the urethral catheter minus that of the guide-wire as 3.0 mm or larger in the corresponding direction