Congenital pouch colons are an anomaly in which there is cystic dilation of a shortened colon. They can either partially or totally replace the colon.
Pathology
Associations
Congenital pouch colons can be associated with vaginal or vestibular fistulas and less frequently with other genitourinary, vertebral, cardiac and/or gastrointestinal anomalies.
Classification
There are different types according to the classification by Narsimha:
- type I: absence of the normal colon, the ileum opens directly into the colonic bag
- type II: ileum reaches a short segment of the cecum, which opens into the bag
- type III: the presence of ascending and transverse colon between the ileum and the colonic bag
- type IV: colonic bag starts from the distal portion of the descending colon
Radiographic features
The initial radiological diagnosis is usually made with a simple abdominal x-ray and/or with fluoroscopy studies with a water-soluble contrast medium. On CT or MR enterography, a tubular structure similar to an intestine with significant dilation may be seen. either attached directly to the ileum or to the colon.