Combined 3D rotational fluoroscopic-MRI cloacagram procedure defines luminal and extraluminal pelvic anatomy prior to surgical reconstruction of cloacal and other complex pelvic malformations

Abstract

Purpose: Cloacal anomalies represent one of the greatest surgical challenges in pediatric surgery. A recent advancement in the imaging of these anomalies is 3D rotational fluoroscopic cloacagram. However, a disadvantage is that obstructed lumens and extraluminal soft tissue structures are poorly delineated. We describe the development of a novel imaging technique whereby 3D rotational fluoroscopy is combined with high-resolution 3D pelvic MR imaging.

Methods: 3D rotational fluoroscopic cloacagram was initially performed. Catheters were directed into the urinary bladder, colon, and vagina. Low-osmolality iodinated contrast material mixed with a small amount of gadolinium contrast material was used to distend the catheterized cavities. After securing the catheters in place, patients underwent high-resolution 3D MRI of the pelvis. 3D MRI reconstructions were created.

Results: 3D rotational fluoroscopic cloacagram provided excellent luminal definition and accurate measurements of channel/fistula lengths, using intraoperative findings as the reference standard. 3D pelvic MRI measurements were easily and accurately made (using intraoperative and 3D rotational fluoroscopic cloacagram as reference standards), and soft tissue structures outside the lumens of the bladder, vagina, and rectum were well-defined. 3D pelvic MRI was able to identify a small vesicovaginal fistula that was not seen at 3D rotational fluoroscopy.

Conclusion: This novel form of preoperative imaging results in excellent delineation channel/fistula lengths, luminal anatomy, and extra-luminal soft tissue structures to aid in operative planning.