Mesenteric ischemia: a radiologic perspective

Advancements in Treatment Strategies for Chronic Mesenteric Ischemia: A Comprehensive Review

Chronic mesenteric ischemia (CMI) arises from the inability to achieve adequate intestinal blood flow after meals, leading to an imbalance between oxygen and metabolite supply and demand. The true incidence of CMI remains uncertain. However, the occurrence of mesenteric artery occlusive disease (MAOD) is relatively common among the elderly population. Delays in diagnosing CMI can often be attributed to several factors, including the variability in patient symptoms and the range of potential causes for chronic abdominal pain with weight loss. Mikkelson pioneered the introduction of a surgical treatment for occlusive lesions of the superior mesenteric artery (SMA) in 1957. The inaugural performance of endovascular revascularization (ER) for visceral vessels took place in 1980. The literature has documented two types of endovascular revascularization (ER) methods: percutaneous transluminal angioplasty (PTA) and primary stenting (PMAS). Despite the limited quality of available evidence, the consensus among experts is strongly in favor of PMAS over PTA alone for the treatment of atherosclerotic mesenteric artery stenosis. There are several key areas of focus for chronic mesenteric ischemia (CMI) treatment. Randomized controlled trials comparing different stent types, such as covered stents versus bare metal stents, are needed to evaluate efficacy, patency rates, and long-term outcomes in CMI patients.

Collateral circulation develops in stenosis of the celiac trunk and superior mesenteric artery

PURPOSE

Mesenteric circulation is provided by the celiac trunk (CT), superior mesenteric artery (SMA), and inferior mesenteric artery (IMA). The collateral circulation between CT and SMA and between SMA and IMA plays a protective role against intestinal ischemia in case of narrowing or occlusion of the mesenteric vessels. In our study, it is aimed to determine the CT and SMA stenosis rates in patients with CT and SMA stenosis from angiography images, the occurrence of the collateral variations, and the frequency of these variations.

METHODS

A total of 408 non-selective or selective CT and SMA angiographic images were taken of 215 patients (130 males, 85 females) who were admitted to Akdeniz University Hospital with symptoms of chronic mesenteric ischemia (CMI) were included. The angiography images were analyzed in regards to CT and SMA stenosis rates, and the collateral variations between mesenteric vessels.

RESULTS

Stenosis of CT was observed in 14 patients, whereas the stenosis of the SMA was observed in 12 patients. The most common collateral vessel in these patients was the gastroduodenal artery. Both stenoses of CT and SMA were found in 9 patients. The Riolan arch was the most common type of collateral vessel in these patients.

CONCLUSION

It was observed that mesenteric circulation was mainly provided by gastroduodenal artery in patients with isolated CT or SMA stenosis or occlusion while in patients with stenosis or occlusion of both CT and SMA, mesenteric circulation was mainly provided by the Riolan arch. A significant increase was observed in the prominence of collateral vessels in patients with stenosis of more than 70%.

Understanding CT imaging findings based on the underlying pathophysiology in patients with small bowel ischemia

Because acute small bowel ischemia has a high mortality rate, it requires rapid intervention to avoid unfavorable outcomes. Computed tomography (CT) examination is important for the diagnosis of bowel ischemia. Acute small bowel ischemia can be the result of small bowel obstruction or mesenteric ischemia, including mesenteric arterial occlusion, mesenteric venous thrombosis, and non-occlusive mesenteric ischemia. The clinical significance of each CT finding is unique and depends on the underlying pathophysiology. This review describes the definition and mechanism(s) of bowel ischemia, reviews CT findings suggesting bowel ischemia, details factors involved in the development of small bowel ischemia, and presents CT findings with respect to the different factors based on the underlying pathophysiology. Such knowledge is needed for accurate treatment decisions.

Pneumatosis intestinalis in abdominal CT: predictors of short-term mortality in patients with clinical suspicion of mesenteric ischemia

Purpose

Pneumatosis intestinalis (PI) in the bowel wall demonstrated in computed tomography (CT) of the abdomen is unspecific and its prognostic relevance remains poorly understood. The purpose of this study was to identify predictors of short-term mortality in patients with suspected mesenteric ischemia who were referred to abdominal CT and showed PI.

Methods

In this retrospective, IRB-approved, single-centre study, CT scans and electronic medical records of 540 patients who were referred to abdominal CT with clinical suspicion of mesenteric ischemia were analysed. 109/540 (20%) patients (median age 66 years, 39 females) showed PI. CT findings were correlated with surgical and pathology reports (if available), with clinical and laboratory findings, and with patient history. Short-term outcome was defined as survival within 30 days after CT.

Results

PI was found in the stomach (n = 6), small bowel (n = 65), and colon (n = 85). Further gas was found in mesenteric (n = 54), portal (n = 19) and intrahepatic veins (n = 36). Multivariate analysis revealed that PI in the colon [odds ratio (OR) 2.86], elevated blood AST levels (OR 3.00), and presence of perfusion inhomogeneities in other abdominal organs (OR 3.38) were independent predictors of short-term mortality. Surgery had a positive effect on mortality (88% lower likelihood of mortality), similar to the presence of abdominal pain (65% lower likelihood).

Conclusions

Our study suggests that in patients referred for abdominal CT with clinical suspicion of mesenteric ischemia, location of PI in the colon, elevation of blood AST, and presence of perfusion inhomogeneities in parenchymatous organs are predictors of short-term mortality.

Graphical abstract

Concealed mesenteric ischemia after total knee arthroplasty: A case report

BACKGROUND

In critical care medicine, mesenteric ischemia (MI) is a life-threatening disease that can be present in both critically ill patients and those undergoing major surgery. For the first time, we report a case of concealed MI with a long course after knee arthroplasty.

CASE SUMMARY

A male patient underwent left total knee arthroplasty for gouty arthritis and developed a persistent fever and persistently high levels of serum infection markers after surgery. He was considered to have a periprosthetic site infection and treated with antibiotics and colchicine, periprosthetic debridement was performed, and the spacer was replaced, but no improvement was seen. At 54 d after arthroplasty, the patient developed gastrointestinal symptoms of nausea and vomiting, abdominal distention, and subsequently, cloudiness of consciousness, and hypotensive shock. Finally, the patient was diagnosed with ascending colonic mesentery ischemia with necrosis after laparotomy, which improved after right hemicolectomy.

CONCLUSION

Concealed MI without gastrointestinal symptoms after major surgery is rare and easily misdiagnosed. Orthopedic surgeons need to be aware of this complication.