Objective: To compare MRI and colostography/fistulography in neonates with anorectal malformations (ARM), using surgery as reference standard. Methods: Thirty-three neonates (22 boys) with ARM were included. All patients underwent both preoperative high-resolution MRI (without sedation or contrast instillation) and colostography/fistulography. The Krickenbeck classification was used to classify anorectal malformations, and the level of the rectal ending in relation to the levator muscle was evaluated. Results: Subjects included nine patients with a bulbar recto-urethral fistula, six with a prostatic recto-urethral fistula, five with a vestibular fistula, five with a cloacal malformation, four without fistula, one with a H-type fistula, one with anal stenosis, one with a rectoperineal fistula and one with a bladderneck fistula. MRI and colostography/fistulography predicted anatomy in 88 % (29/33) and 61 % (20/33) of cases, respectively (p = 0.012). The distal end of the rectal pouch was correctly predicted in 88 % (29/33) and 67 % (22/33) of cases, respectively (p = 0.065). The length of the common channel in cloacal malformation was predicted with MRI in all (100 %, 5/5) and in 80 % of cases (4/5) with colostography/fistulography. Two bowel perforations occurred during colostography/fistulography. Conclusions: MRI provides the most accurate evaluation of ARM and should be considered a serious alternative to colostography/fistulography during preoperative work-up. Key Points: • High-resolution MRI is feasible without the use of sedation or anaesthesia. • MRI is more accurate than colostography/fistulography in visualising the type of ARM. • MRI is as reliable as colostography/fistulography in predicting the level of the rectal pouch. • Colostography/fistulography can be complicated by bowel perforation.

Anorectal malformation, Colostography, Fistulography, MRI, Neonates
dx.doi.org/10.1007/s00330-015-3786-0, hdl.handle.net/1765/82555
European Radiology: journal of the European Congress of Radiology
Department of Radiology

Thomeer, M.G.J, Devos, A.S, Leguin, M, De Graaf, N, Meeussen, C.J.H.M, Meradji, M, … Sloots, C.E.J. (2015). High resolution MRI for preoperative work-up of neonates with an anorectal malformation: a direct comparison with distal pressure colostography/fistulography. European Radiology: journal of the European Congress of Radiology, 25(12), 3472–3479. doi:10.1007/s00330-015-3786-0