- “The median arcuate ligament syndrome (or celiac artery compression syndrome) was first described in 1963 by Harjola (3). The definition of the syndrome relies on a combination of both clinical and radiographic features. It typically occurs in young patients (20–40 years of age) and is more common in thin women, who may present with epigastric pain and weight loss (4). The abdominal pain may be associated with eating, but not always (5). At physical examination, an abdominal bruit that varies with respiration may be audible in the midepigastric region. Symptoms are thought to arise from the compression of the celiac axis, resulting in a compromise in blood flow.”
A postoperative aneurysm may be either a “true” aneurysm that includes all layers of the vascular wall or a pseudoaneurysm, such as occurred in our patient. A true aneurysm can occur if the native aorta is not excised to the level of the renal arteries at the original surgery, which leaves a segment of aorta that is susceptible to aneurysm formation. Potential causes of pseudoaneurysm formation include technical error and infection. Graft infections are a potentially important causal factor in pseudoaneurysm formation. Some studies have found that more than 50% of pseudoaneurysms without clinical evidence of infection are in fact culture positive. The most frequently isolated organisms have been Staphylococcus epidermidis and other staphylococcal species. It is theorized that these bacteria release cytolysins, which can result in graft disruption.
“ A postoperative aneurysm may be either a “true” aneurysm that includes all layers of the vascular wall or a pseudoaneurysm, such as occurred in our patient. A true aneurysm can occur if the native aorta is not excised to the level of the renal arteries at the original surgery, which leaves a segment of aorta that is susceptible to aneurysm formation. Potential causes of pseudoaneurysm formation include technical error and infection. Graft infections are a potentially important causal factor in pseudoaneurysm formation.”
Aortic Pseudoaneurysm
Takach TJ, Cervera RD, Gregoric ID
Tex Heart Inst J 2005; 32(2): 235-237 - “ Once the disorder has been diagnosed, surgery can be performed to relieve the compression. In some patients, the ligamentous constriction of the celiac axis causes vascular damage, which may require vascular reconstruction. CT angiography can play a role in the diagnosis of median arcuate ligament syndrome by demonstrating the characteristic focal narrowing of the celiac artery in patients presenting with the appropriate clinical symptoms.”
Median Arcuate Ligament Syndrome: Evaluation with CT Angiography
Horton KM, Talamini MA, Fishman EK
RadioGrapgics 25.1177-1182 - “ The median arcuate ligament is a fibrous arch that unites the diaphragmatic crura on either side of the aortic hiatus. The ligament usually passes superior to the origin of the celiac axis. However, in some people, the ligament inserts low and thus crosses the proximal portion of the celiac axis, causing compression and sometimes resulting in abdominal pain. The diagnosis of clinically significant celiac axis compression, referred to as median arcuate ligament syndrome, is traditionally made with conventional angiography; however, the condition can now be diagnosed with three-dimensional computed tomographic (CT) angiography. In patients with median arcuate ligament syndrome, CT angiograms demonstrate a characteristic focal narrowing in the proximal celiac axis. The focal narrowing has a characteristic hooked appearance, which can help distinguish this condition from other causes of celiac artery narrowing, such as atherosclerotic disease.”
- Celiac and SMA Dissection: Facts
-Usually isolated finding but both vessels can be involved in up to 10% of cases
-Clinical presentation is persistent abdominal pain but most cases are incidental findings
-Treatment may be conservative (anticoagulation, analgesics and beta blockade)
-Intervention may be necessary with persistent symptoms, expansion of the false lumen or true lumen compromise - "Although splanchnic artery aneurysms are relatively rare, they are being diagnosed with increased frequency given the widespread availability of MDCT and 3D imaging capabilities."
MDCT and 3D CT Angiography of Splanchnic Artery Aneurysms
Horton KM, Smith C, Fishman EK
AJR 2007;189:641-647
- "Although splanchnic artery aneurysms are relatively rare, they are being diagnosed with increased frequency given the widespread availability of MDCT and 3D imaging capabilities. It is important that these aneurysms be diagnosed accurately because they can carry a high morbidity and mortality, even in asymptomatic patients."
MDCT and 3D CT Angiography of Splanchnic Artery Aneurysms
Horton KM, Smith C, Fishman EK
AJR 2007;189:641-647
- Splanchnic Artery Aneurysms: Facts
- Incidence of 0.01-0.2% in autopsy series
- Most common is splenic artery aneurysm (60%), with hepatic artery aneurysm being second most popular (20%)
- Aneurysm rupture is associated with high morbidity and mortality
- Splanchnic Artery Aneurysms: Facts
- Splenic artery (60%)
- Hepatic artery (20%)
- SMA (5.5%)
- Celiac artery (4%)
- Pancreatic arteries (2%)
- Gastroduodenal artery (GDA) 1.5%
- Splenic Artery Aneurysms: Facts
- 4x more common in woman than men
- In woman association with pregnancy and multiparity
- Although more common in woman more likely to rupture in men
- Risk of rupture (2-3%) increases with pregnancy, portal hypertension, and after liver tralntation
- Vasculitides that involve the GI Tract
- Takayasu arteritis
- Polyarteritis nodosa
- Wegener granulomatosis
- Churg-Strauss syndrome
- Microscopic polyangitis
- SLE
- Rheumatoid vasculitis
- "Unsuspected mesenteric arterial abnormality may elude diagnosis when axial MDCT sections are interpreted without 3D renderings."
Unsuspected Mesenteric Arterial Abnormality: Comparison of MDCT Axial Sections to Interactive 3D Rendering
Chen JK, Johnson PT, Horton KM, Fishman EK
AJR 2007;189:807-813
- "In the era of isotropic data, perhaps the new standard of care will be to review all MDCT data sets in 3D mode to exclude any unsuspected vascular abnormality."
Unsuspected Mesenteric Arterial Abnormality: Comparison of MDCT Axial Sections to Interactive 3D Rendering
Chen JK, Johnson PT, Horton KM, Fishman EK
AJR 2007;189:807-813
- "This ability to visualize the mesenteric vasculature in real-time using 3D rendering and multiplanar reconstruction is crucial for the comprehensive review of the complex mesenteric vessels."
Mesenteric CT Angiography: A Discussion of Techniques and Selected Applications
Smith Cl, Horton KM, Fishman EK
Tech Vasc Interventional Rad 9:150-155, 2006
- "As CT scanners and 3D imaging software continue to advance, it is very likely that in the near future 3D imaging of the abdomen and abdominal vasculature will become a routine method for review of all CT exams rather than a specialized separate process done in select cases."
Mesenteric CT Angiography: A Discussion of Techniques and Selected Applications
Smith Cl, Horton KM, Fishman EK
Tech Vasc Interventional Rad 9:150-155, 2006
- "Although splanchnic artery aneurysms are relatively rare, they are being diagnosed with increased frequency given the widespread availability of MDCT and 3D imaging capabilities. It is important that these aneurysms be diagnosed accurately because they can carry a high morbidity and mortality, even in asymptomatic patients."
MDCT and 3D CT Angiography of Splanchnic Artery Aneurysms
Horton KM, Smith C, Fishman Ek
AJR 2007; 189:641-647
- Inferior Phrenic Artery: Facts
- arise usually from aorta or celiac axis in most cases. May also arise from the renal arteries
- IPA is a common source of extrahepatic collateral blood supply for hepatomas
- IPA may also be involved in hemoptysis, hepatic bleeding or gastroesophageal issues like Mallory Weiss or GE cancer
- Median Arcuate Ligament Syndrome: Facts
- AKA celiac artery compression syndrome
- Median arcuate ligamnet is formed by muscular fibers that connect the left and right crura of the diaphragm
- May lead to intestinal angina
- Most patients asymptomatic
- Pseudo-celiac artery compression may be seen on expiratory phase images
- "Multidetector CT may offer a distinct advantage over traditional single-detector CT in the evaluation of mesenteric vasculature.Narrower collimation coupled with shorter scanning times reduces motion artifact and permits scanning during peak IV Contrast enhancement, which improves both axial and reformatted images."
Bowel Obstruction Revealed by Multidetector CT
Khurana B et al.
AJR 2002;178:1139-1144
- Polyarteritis Nodosa: Facts
- Systemic necrotizing vasculitis that affects small and medium size arteries
- GI tract involvement is seen in up to 50% of patients
- Common sites of involvement; kidneys, heart, liver, CNS and skin
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