[Collateral circulation of the left colon: historic considerations and actual clinical significance]

Evaluation of characteristics of left-sided colorectal perfusion in elderly patients by angiography

BACKGROUND

Handling of the inferior mesenteric artery (IMA) and maintaining anastomotic perfusion are important in radical resection of left-sided colorectal cancer. However, the branching of this artery and the drainage patterns of this vein vary among individuals, and the characteristics and perfusion region of this artery in elderly patients remain unclear.

AIM

To evaluate the characteristics and perfusion region of the IMA in elderly patients using angiography.

METHODS

We enrolled 154 patients (> 65 years old) who underwent digital subtraction angiography of the IMA. The characteristics, bifurcation, and distribution of the IMA and termination of the anastomotic perfusion of the left colon and rectum were examined using digital subtraction angiography. Collateral arterial arches and the IMA hemoperfusion region were also recorded. Perfusion regions were cross-referenced with clinical and anatomical features by the univariate analysis.

RESULTS

Of 154 patients, 25 (16.2%) had IMA lesions. The left colic artery arose independently from the IMA in 44.2% of patients, shared a trunk with the sigmoid artery in 35.1%, shared an opening with the sigmoid and superior rectal arteries in 16.9%, and was absent in 5.1%. The IMA perfusion region stopped at the splenic flexure in 50 (32.5%) patients. The collateral circulation existed in the colonic perfusion region, including the marginal artery (Drummond’s artery), the ascending branch of the left colonic artery to supply the transverse colon, and the arc of Riolan with a frequency of 100%, 22.7%, and 1.9%, respectively. The IMA perfusion region was independently associated with the comorbidity of atherosclerosis, IMA atherosclerotic lesion, branching pattern, collateral circulation, and marginal artery integrity.

CONCLUSION

The IMA and its branches are prone to arteriosclerosis, and IMA perfusion may be interrupted at the splenic flexure in elderly patients. The applicability and precision of preoperative angiography for evaluating the IMA branching and perfusion patterns could facilitate geriatric laparoscopic left-sided colorectal cancer surgery with suspicion of poor IMA perfusion.

Novel Visceral-Anastomosis-First Approach in Open Repair of a Ruptured Type 2 Thoracoabdominal Aortic Aneurysm: Causes behind a Mortal Outcome

Case reports to analyze causes and possible prevention of complications in a new setting are important. We present an open repair of a ruptured type 2 thoracoabdominal aortic aneurysm in a 78-year-old man. Lower-body perfusion through a temporary extracorporeal axillobifemoral arterial prosthesis shunt was combined with the use of a branch to the permanent aortic prosthesis to enable rapid visceral revascularization using a visceral-anastomosis-first approach. The patient died due to transfusion-induced capillary leak syndrome and left colon necrosis; the latter was probably caused by a combination of back-bleeding from lumbar arteries causing a steal effect, an accidental shunt obstruction, and hemodynamic instability towards the end of the operation. The visceral-anastomosis-first approach did not contribute to the complications. This approach reduces the time when visceral organs are perfused only via collateral arteries to the time needed for suturing the visceral anastomoses. This may be important when collateral perfusion is marginal.

Temporary extracorporeal brachio-femoral vascular prosthesis shunt for ischemia prevention in an operation for abdominal aortic and iliac aneurysms in a patient with Marfan's syndrome

In open vascular repair, when prolonged infrarenal aortic clamping can be expected, and collateral perfusion is reduced, the use of a temporary shunt may reduce the risk of ischemic complications. In a patient with Marfan's syndrome and aortic dissection who had developed infrarenal aneurysms, segmental arteries had been occluded by prior aortic surgery and collateral arteries in the anterior torso could have been damaged by previous pectus excavatum, muscle flap, sternotomy, and ventral hernia operations. The axillary artery was dilated. For the prevention of ischemia during open repair with a bifurcated graft, a temporary extracorporeal brachio-femoral vascular prosthesis shunt was constructed. Ischemia was not observed. The use of a temporary extracorporeal brachio-femoral shunt with a vascular prosthesis is a feasible method for ischemia prevention.

Bridging the gap with an ileocolonic graft after extensive colorectal resections

BACKGROUND

Ileocecal interposition (ICI) for first-line reconstruction after low anterior colorectal resection was introduced by von Flüe and Harder in 1994 (Dis Colon Rectum 37:1160-1162, 1994). We report our experience using this technique to bridge colonic gaps after significant loss of bowel length.

PATIENTS AND METHODS

Between 1999 and 2009 the left-sided colon was too short for traditional isoperistaltic reconstruction in six patients treated in our hospital. Reasons for extensive bowel loss were a deficient (n = 3) or torn (n = 1) marginal artery with ischemia or repeat colorectal resections (n = 2). An ICI was done to bridge the gap and enable restoration of intestinal continuity.

RESULTS

No patient died. Whenever performing a coloanal anastomosis (4/6) a loop ileostomy was raised. One patient with colonic diversion experienced graft-related complications: ischemic colitis of the interposed colonic segment, anastomotic stenosis, and a presacral sinus were observed and managed nonoperatively. Subsequent closure of the stoma was possible in all cases. A median Vaizey incontinence score of 9 (range: 4-14) was recorded in the patient with coloanal anastomosis. The average number of bowel movements per day was 1.5 (range: 0.5-6).

CONCLUSIONS

When the descending colon does not reach the rectal stump or anal canal in reoperative cases or after vascular complication, ICI is a useful salvage procedure resulting in good bowel function.

Anatomical variations of the coeliac trunk and the mesenteric arteries evaluated with 64-row CT angiography

PURPOSE

This study was undertaken to evaluate the accuracy of 64-row computed tomography angiography (CTA) in the study of vascular anatomy by assessing the incidence of anatomical variations of the origin of the coeliac trunk, mesenteric arteries and collateral branches.

MATERIALS AND METHODS

Sixty patients were evaluated with 64-row CTA (VCT, General Electric Healthcare, Milwaukee, WI, USA) with a collimation of 0.625 mm after the injection of iodinated nonionic contrast material (4 ml/s). Exclusion criteria were the presence of any pathological condition likely to affect normal vascular anatomy.

RESULTS

The coeliac trunk had a normal trifurcation in 56.7% of cases. The common hepatic artery was normal in 60% of patients. The inferior pancreaticoduodenal arteries were either absent or not assessable in 8.3% of cases and there was a double trunk in 5%, a common trunk in 83.3% and a single vessel in 3.3%. The number of jejunal and ileal arteries ranged from a minimum of six to a maximum of 13 (mean value 8.7+/-1.34). The Riolan arcade was assessable in 31.7% and developed in 68.4% of these.

CONCLUSIONS

The 64-row CTA enables visualisation of small vessels and accessory arteries that are difficult to identify with other techniques. The technique's high sensitivity allowed us to observe that the prevalence of vascular abnormalities is higher than that reported in the literature.

Macroscopic and microscopic intermesenteric communications

The aim of this study was to describe all levels of the intermesenteric communications because of their importance in vascular diseases of the colon. The connections of superior and inferior mesenteric networks are very important in cases of acute or chronic obstruction to prevent ischemia and necrosis. Angiograms of mesenteric arteries were studied (40), cadaverous large intestine samples with mesentery and feeding vessels were dissected (36) or injected with India ink solution (24) or methylmetacrylate Mercox (41). In 7.9 % of cases an intermesenteric connection was described, named anastomosis intermesenterica accessoria and classified according to Pikkieff's(1) proposal. The marginal artery in the left colic flexure forms an arch called Riolan's arcade(2) or Haller's anastomosis(3) and is present in 95 % of cases. Infrequent anastomosis between straight vessels and mighty plexuses in the intestinal wall were registered. There are no regional differences when compared to the rest of colon.