Imaging of anorectal malformations in utero.

PURPOSE: To document the imaging findings suggestive of anorectal malformation (ARMs) on prenatal US and MRI.

METHODS

Retrospective evaluation of the screening US and prenatal MRI exams of the rectum and ano-perineal region in normal fetuses and in patients with ARMs.

RESULTS

Examples showing the normal rectal and anoperineal anatomy on prenatal US and MRI exams and the imaging findings observed in different types of confirmed ARMS.

CONCLUSIONS

Prenatal diagnosis of ARMs requires both a systematic evaluation of the fetal pelvis and perineum and an appropriate knowledge of its suggestive imaging findings.