Ischemic colitis after abdominoperineal resection.

: Four cases of ischemic colitis occurring at intervals from 3 months to 7 years after abdominoperineal resection are described. In 3 of the 4 cases patency of the direct arterial supply to the ischemic segment was documented. The lack of collateral circulation provided by the resected colon probably increases the risk of developing ischemic colitis in the remaining colon.