Colonic duplication

An uncommon congenital abnormality. Patients usually present with constipation but acute obstruction is less commonly reported.

The pathogenesis remains unknown and hypotheses have been proposed:

i. Incomplete recanalisation of the digestive tract lumen
ii. Intrauterine vascular insufficiency secondary to foetal stress and anoxia

Colonic and rectal duplication may be cystic or tubular, the latter more common in the rectum. It is usually segmental and can be classified into the various types:

Type 1 Segmental colonic duplication without other caudal duplication

a. Non-communicating spherical duplication
b. Non-communicating tubular duplication
c. Communicating tubular duplication

Type 2 Complete or segmental colonic duplication with genitourinary duplication

a. Duplication with two perineal openings
b. Duplication with one or both segments ending as a fistula to the vagina, bladder or perineum
c. Duplication with one or both segments imperforate and no fistula

Patient Case Example of Type IIa Colonic Duplication.


Fig a. Selected post contrast axial CT image slice demonstrating a duplicated anorectal junction and cervix.
Fig b. Selected post contrast coronal CT image illustrating a duplicated rectum
Fig c. Selected post contrast axial CT image confirming duplicated sigmoid colon and uterus
Fig d. Selected post contrast axial CT image demonstrating a duplicated descending colon
Fig e. Selected post contrast coronal CT image of a duplicated splenic flexure
Fig f. Selected post contrast coronal CT image of a duplicated caecum



References:

1. Congenital anomalies of the small intestine, colon, and rectum. Berrocal T, Lamas M, GutieƩrrez J, Torres I, Prieto C, del Hoyo ML. Radiographics. 1999 Sep- Oct;19(5):1219-36.
2. Duplication of the colon: varied presentations of a rare congenital anomaly. Carr SL, Shaffer HA Jr, de Lange EE. Can Assoc Radiol J. 1988 Mar;39(1):29-32.