CASE 5218 Published on 28.02.2007

The arch of Bühler in chronic mesenteric ischemia

Section

Cardiovascular

Case Type

Clinical Cases

Authors

P. Argyriou , G.E. Karagiannis , Ch. Bourgioti , K. Chatoupis , D. Tsocanas

Patient

74 years, male

Clinical History
A 74-year-old patient, came to our hospital with clinical signs of abdominal angina. A multislice CT angiography of mesenteric vessels, a 3D reconstruction and a conventional angiography took place and a rare collateral, due to chronic superior mesenteric artery thrombosis, called arc of Bühler was clearly demonstrated.
Imaging Findings
A 74-year-old man, with a known history of abdominal aortic aneurysm, referred to our hospital complaining for chronic postprandial abdominal pain with weight loss and anorexia. The pain was crampy and usually appeared 30 minutes after eating, steadily increased and resolved 2 hours later. The symptoms were highly suggestive of mesenteric angina. A MSCT angiography of the mesentery artery performed with 1.25 slice thickness, 150 ml contrast volume of non ionic iodinate contrast medium (concentration 370mg/dl), 5ml/sec flow rate and a bolus triggering protocol. The multiplanar and the three –dimensional reconstruction in an advanced workstation demonstrated superior mesenteric artery (SMA) occlusion (Fig. 1) and the presence of collateral vasculature. The main collateral network which supplied the SMA was an unusual embryonic remnant between the celiac artery and the proximal trunk of SMA, the arch of Bühler. Conventional angiography confirmed the diagnosis (Fig. 2).
Discussion
Chronic mesenteric ischemia (intestinal angina) refers to episodic or constant intestinal hypoperfusion, resulting from a blood supply, insufficient to satisfy the metabolic demands of post-pradial bowel activity. The occurrence of ischemia is a multifactor event. It depends on the number of proximal arterial lesions, the site of the lesion, the rate of the lesion progression and the ability of the individual patient to develop collateral vessels. Knowledge of the anatomy of the mesenteric vessels is key in understanding and treating patients with mesenteric ischemia. The gastrointestinal tract supplied by the celiac artery (CA), superior mesenteric artery (SMA) and inferior mesenteric artery (IMA), which usually originate from the abdominal aorta. Common trunks and anastomoses are possible between two of these arteries and are documented in literature. The collateral vessels that develop in patients with visceral artery stenosis or occlusion can be divided into two major systems (1). The first major system connects the celiac artery to the superior mesenteric artery. Mainly is composed of the pancreaticoduodenal arteries running between the gastroduodenal artery and the proximal SMA. Also, the left epiploic artery (arises from left gastroepiploic) and the right epiploic artery (from right gastroepiploic or less often the transverse pancreatic artery) forms the epiploic arch (arch of Barkow), providing small branches to the transverse colon. A direct connection between the proximal segments of celiac artery and SMA may be identified on occasion, although its presence is rather rare and untypical. This represents an embryonic remnant and is known as the arch of Bühler. Embryologically, the arch of Bühler (2 ,3 ), is explained by the persistence of the 10th and the 13th primitive arteries, which are associated with the persistence of the ventral anastomosis between these two arteries. In our case it is the prominent collateral pathway and its identification is significant for patients treatment and prognosis. The other system connects the SMA to the IMA and comprises the paracolic arcade (Riolan arch) and the marginal arteries of Drummond and Dwight. The arch of Riolan provides a direct connection between the SMA and IMA via the middle and the left colic arteries at the splenic flexure. The marginal arteries of Dwight and Drummond supply the vasa recta to the small intestine and colon and provide a continuous channel of potential collateral blood supply to the entire gut. When all three visceral arteries (CA, SMA, IMA) are stenotic or occluded, phrenic, lumbar, and pelvic collateral vessels become prominent. Biplanar selective angiography is considered to be the gold standard for diagnosis of vascular disease. Multiplanar CT angiography is an excellent alternative with high sensitivity (96%) and specificity (94%), although there are no randomized controlled trials comparing multi-detector CT with conventional angiography for the diagnosis of chronic mesenteric ischemia. Three-dimensional imaging allows a better representation of the complex vascular collaterals and provides an excellent roadmap for the surgeons, since untypical collaterals, such as the arch of Bühler could be clearly demonstrated.
Differential Diagnosis List
Arch of Bühler
Final Diagnosis
Arch of Bühler
Case information
URL: https://www.eurorad.org/case/5218
DOI: 10.1594/EURORAD/CASE.5218
ISSN: 1563-4086