[Clinical application of magnetic resonance imaging in congenital anorectal malformation].

OBJECTIVE: To investigate the clinical value of MRI examination in congenital anorectal malformation (CARM).

METHOD: Forty-four cases with operatively proved anorectal malformation from May 2008 to May 2012 in the authors' hospital were reviewed. Of the 44 cases, 25 were males and 19 females, their age ranged from 1 day to 2 years. MRI was performed in all patients.

RESULT: Of all 44 cases, 15 cases had high imperforate anus (34%), rectum blind end were above PC line, the distance of rectum blind end and anus nest was (29.12 ± 2.35) mm; 8 cases had median imperforate anus (18%), rectum blind ends were near PC line, the distance of rectum blind end and anus nest was (18.98 ± 2.21) mm; 21 cases had low imperforate anus (48%), rectum blind ends were below PC line, the distance of rectum blind end and anus nest was (7.54 ± 1.08) mm. Twenty-five cases with fistula in 44 cases were confirmed by rectal angiography and surgery, accounting for 57%. In 13 cases with fistula, the lesion could be clearly demonstrated on MRI, in the remaining 12 cases with fistula, the lesion could not be visualized clearly or no image development occurred on MRI. Of all 44 cases, 1 case had tethered cord with filum terminale lipoma, 1 case had tethered cord, 2 cases had syringomyelia, 1 case had right kidney agenesis, 1 case had hydrocele. In 44 cases of multi-planar MRI imaging could clearly show the perianal muscles developmental situation, 36 cases had perianal muscles dysplasia, amd showed levator ani muscle, puborectalis and anal sphincter asymmetry, muscle belly slim.

CONCLUSION: MRI examination has a high clinical value in CARM diagnosis, can help accurately judge the anal atresia type, display the presence and running of most of the fistula, and diagnose perianal muscle development and other systems malformations, finally provide a reliable diagnostic basis for surgical program and prognostic assessment.