It's commonly recognized that the splenic flexure of the colon is vulnerable to hypotensive ischemia (ischemic colitis) since it's at the boundary between the SMA and IMA vascular distributions. This vascular territory is also a crucial connection between the two circulations if there is there is ligation or coiling of the IMA, allowing collateral circulation to flow into the splenic flexure and descending colon.
|Lack of an anastosmosis at Griffith's point puts the splenic flexure of the colon at risk: MC (middle colic artery), ALC (ascending left colic), MA (Marginal Artery (of Drummond). (ref 1)|
What may not be as well known is that the anastomosis between the middle colic and the Marginal artery of Drummond may not exist in nearly half of people. In one often quoted study from 1976, in 43% (20/46) of people, the Marginal Artery of Drummond anastomosis from the two circulations is not seen on arteriography (and assumed not to exist).
As mentioned above, recognition of this finding may alter operative approach toward the IMA, to reduce risk of future ischemic colitis.
1. Myers MA. "Griffiths' point: critical anastomosis at the splenic flexure. Significance in ischemia of the colon" AJR (Jan 1976) Vol 126:1 pp 77-94.