3-Dimensional magnetic resonance genitography: a different look at cloacal malformations

Abstract

Purpose: Standard contrast genitography and endoscopy have been the cornerstone of preoperative investigation of anatomy in complex cloacal malformations. In many cases standard genitography is ambiguous and lengthy endoscopy may be required to define the anatomy. Nonenhanced magnetic resonance imaging lacks definition of the nondistended common channel and confluence. To our knowledge we introduce 3-dimensional magnetic resonance genitography for delineating the unique anatomical features of these complex anomalies.

Materials and methods: Contrast genitography, endoscopy and 3-dimensional magnetic resonance genitography were performed preoperatively in 4 female infants with cloacal malformations. Three-dimensional magnetic resonance genitography was performed using a 3-dimensional spoiled gradient technique after the instillation of gadolinium-diethylenetetramine pentaacetic acid solution via the common channel and cutaneous vesicostomy, when present. Augmented pressure distal colostogram with gadolinium via the mucous fistula was included. Three-dimensional images were constructed using a commercially available workstation.

Results: Three-dimensional magnetic resonance genitography yielded anatomical information far superior to that of standard genitography in all cases and it provided information on female genital tract anomalies and hindgut confluence that were not fully appreciated at initial endoscopy. The confluence was most accurately represented by augmented pressure colostogram. The length of the common channel was consistent with that on endoscopy. Rotating 3-dimensional images illustrated the unique anatomical relationships. No magnetic resonance imaging specific complications were observed.

Conclusions: Three-dimensional magnetic resonance genitography provides superior anatomical detail for the preoperative assessment of cloacal malformations. It augments the information obtained by standard magnetic resonance imaging of the pelvic organs, levators and lumbosacral spine. Three-dimensional magnetic resonance genitography has great potential as a standard for preoperative anatomical evaluation and it will likely simplify preoperative endoscopy rather than supplant it.