Objective:

To explore the value of pelvic floor three-dimensional ul

trasound (3DUS) reconstruction in detecting the distal rectal pouch and the levator ani muscle around the rectum

and the thickness of levator ani muscle in the diagnosis of congenital anorectal malformation (CARM).

Methods:

Fifty-six cases of CARM were examined by pelvic floor 3DUS. The distance between distal rectal pouch and perineum (P-P distance)

the distance between distal rectal pouch and levator ani muscle (P-L distance) and the thickness of levator ani muscle and sphincter ani muscle thickness were measured. Meanwhile

the development of pelvic floor muscles in 42 cases with CARM was evaluated by magnetic resonance imaging (MRI). The classification of CARMby 3DUS was analyzed

and the diameters of the pelvic floor muscles measured by 3DUS and MRI were compared. The diagnostic efficacy of the two methods for CARM with fistula was also discussed.

Results:

The P-P distance

P-L distance and the thickness of levator ani muscle between groups measured by 3DUS had statistical significance (

P

0.05). The average P-P distance

levator ani muscle thickness and sphincter ani muscle thickness measured by 3DUS in 56 cases of CARM were (10.654.62)

(2.140.40) and (1.360.41)

respectively

and the average P-P distance

levator ani muscle thickness and sphincter ani muscle thickness measured by MRI in 42 cases were (11.474.84)

(2.120.36) and (1.320.38) mm

respectively

there was no significant difference between the two groups (

P

0.05). Compared with the results of operation

3DUS indicated that there were 28 cases with fistula and 7 cases without fistula

and the sensitivity

specificity and accuracy of diagnosis were 65.1%

53.8% and 62.5%

respectively. MRI indicated 21 cases with fistula and 5 cases without fistula. The sensitivity

specificity and accuracy of diagnosis were 63.6%

55.6% and 61.9%

respectively. There was no significant difference between the two groups (2=0.006

P

=0.940).

Conclusion:

Pelvic floor 3DUS reconstruction tech

nology can visually and stereoscopically display the position of dilated distal rectal pouch and levator ani muscle around it

and accurately measure the thickness of levator ani muscle. It improves the shortcomings of the previous single ultrasound method for measuring the distance between dilated distal rectal pouch and perineum

and can improve the accuracy of ultrasound diagnosis and classification of CARM.