Post-operative magnetic resonance evaluation of children after laparoscopic anorectoplasty for imperforate anus.

BACKGROUND AND AIMS

Laparoscopic anorectoplasty (LAR) is a relatively new procedure in the treatment of imperforate anus. Using magnetic resonance imaging (MRI), we evaluated the anatomical features of the anorectal region of children treated with LAR and compared this with conventional posterior sagittal anorectoplasty (PSARP). The findings were correlated with functional outcome.

PATIENT/METHODS: A retrospective review of ten children with the high/intermediate types of imperforate anus underwent LAR between May 2000 and December 2002. MRI of the pelvis was performed post-operatively and a semi-quantitative score was used to assess the degree of sphincter symmetry, peri-rectal fibrosis, and the position of the pull-through rectum. The defecation status of these patients was also recorded. Eight historical patients who had undergone PSARP served as a control group.

RESULTS/FINDINGS: When compared with PSARP patients, a significantly lower proportion of LAR patients had sphincter asymmetry (40 vs. 100%, p < 0.05) and peri-rectal fibrosis (40 vs. 87.5%, p < 0.05). The positioning of the rectum was, however, central for both groups (90 vs. 87.5%). No statistical correlation was found between defecation status and the degree of sphincter asymmetry or peri-rectal fibrosis.

INTERPRETATION/CONCLUSION: LAR allows more optimal anatomical reconstruction for patients with the high/intermediate types of imperforate anus. However, additional factors that are not correctable by surgery, such as intrinsic innervation deficiency, also influence the clinical outcome.