Table 1.

Classification provided by McPherson AG.

Type	position	structure	Blood supply	clinical feature
I	In the mesentery of the colon, either next to or away from the intestinal wall	Composed of intestinal epithelium	The blood supply is inseparable from that of the adjacent intestinal canal.	Palpable masses or intestinal obstruction
II	The margin of the mesentery or the reverse mesentery	The lumen of the diverticulum is lined with intestinal mucosa, but not necessarily of the colonic type.	Blood supply is intertwined with that of the adjacent colon.	A mass in the abdomen
III	A long repetitive malformation with the duplicated bowel partially parallel to the normal bowel	Normal mucosal lining	Consistent with the blood supply to the adjacent intestine	If both colons can empty freely, there can be no symptoms.