[The angiographic anatomy of the inferior mesenteric artery in elder]

Objective: To examine the characteristics of the digital subtraction angiography of inferior mesenteric artery (IMA) in elderly Chinese patients over 65 years old. Methods: Totally 64 cases who underwent angiography of IMA were selected from the Department of General Surgery, Xuanwu Hospital of Capital Medical University, including 42 males and 22 females, aging (70.9±5.1) years (range: 60 to 88 years). The origin, diameter and trunk length of IMA were analyzed. The distribution of IMA branching and the relationship between LCA and IMV at the level of IMA opening position were revealed. Also, the range of IMA perfusion, Riolan arch and IMA occlusion were observed. Results: All 64 patients underwent IMA angiography successfully. The diameter of IMA was (3.2±0.5) mm (range: 2.6 to 4.4 mm), and the trunk length was (3.8±1.0) cm (range: 1.1 to 7.0 mm). According to IMA classification standard, there were 26 patients with type Ⅰ (40.6%), 24 patients with type Ⅱ (37.5%), 12 patients with type Ⅲ (18.8%), 2 patients with type Ⅳ(3.1%). The horizontal distance between IMV and LCA was less than 0.5 cm in 58 cases (90.6%) and more than 0.5 cm in 6 cases (9.4%). IMA perfusion was interrupted at the splenic flexure in elderly patients in 14 cases (21.9%), including 11 cases terminated at splenic flexure and 3 cases terminated at descending colon. Riolan arch was found in only 4 of 64 patients (6.2%). Two patients (3.1%) had IMA or its branch occlusion, the arterial perfusion were compensated by Drummond arch without Riolan arch. Conclusions: The anatomy of IMA should be taken attention seriously in laparoscopic left-colorectal cancer radical resection. IMA shape, type, blood supply range and the relationship between LCA and IMV could be considered by the angiography or other examination, which can help to determine the ligation position of blood vessels, which could optimize the operation strategy.