Three-dimensional endoanal ultrasonographic assessment of an anal fistula with and without H2O2 enhancement

Table 3 Results of physical examination and 3D-EAUS findings in localization of the internal opening

	Classification based on surgical findings (No. of internal openings detected)				Overall accuracy
	Anterior (12)	Left lateral (8)	Posterior (31)	Right lateral (6)
Physical examination
Anterior	61	0	0	0
Left lateral	2	51	1	0
Posterior	0	1	201	1	59.7% (34/57)a
Right lateral	0	0	2	31
3D-EAUS
Anterior	101	0	1	0
Left lateral	0	61	0	0
Posterior	0	1	261	0	84.2% (48/57)b
Right lateral	0	0	1	61
H2O2 3D-EAUS
Anterior	101	0	1	0
Left lateral	0	71	0	0
Posterior	0	0	281	0	89.5% (51/57)c
Right lateral	0	0	1	61

¹Absolute agreement; P = 0.004 between a and b, P = 0.001 between a and c, P = 0.406 between b and c.