Teaching Case

An 18 year-old-female patient presented with chronic epigastric pain, often precipitated in the post-prandial period.

Sagittal contrast-enhanced CT (CECT) image of abdomen revealed severe stenosis at the origin of celiac artery with post-stenotic dilatation of the proximal celiac trunk. A fibrous band was seen traversing anteriorly and over the celiac axis causing focal stenosis at the origin of celiac trunk with post-stenotic dilatation resulting in hook-shaped deformity of the proximal celiac trunk (Fig. 1). Volume rendered 3D-images also demonstrate narrowing at the origin of celiac axis with post-stenotic dilatation leading to a hooked appearance (Fig. 2, Fig. 3).

Dr. Harjola first described the Median Arcuate Ligament Syndrome (MALS) in 1963 [1]. It is also known as Dunbar syndrome or celiac artery compression syndrome. It is a rare syndrome characterised by recurrent epigastric pain, nausea and weight loss. It is caused by narrowing of the celiac artery by median arcuate ligament (MAL), which is a fibrous arch connecting right and left diaphragmatic crura located on either side of aorta [2]. This abnormal position of MAL compresses the vasculature and surrounding neural ganglion, manifesting typically as post-prandial discomfort. In normal subjects, MAL is located superior to the origin of celiac axis. However, in a small proportion of patients, MAL is relatively low-lying and traverses anterior to the origin of celiac artery. At this aberrant location, it narrows the lumen of the celiac axis leading to insufficient blood supply to the foregut derivatives. It is commonly seen in young thin female patients between 20-40 years of age [3].

The symptomatology of MALS is typically worsened during the expiration as celiac artery moves cranially during expiration. It is relieved during the inspiration as celiac artery descends to the abdominal cavity during inspiration because of vertical orientation of the celiac axis. However, abundant collateral supply in gut leads to very few patients actually presenting with classic symptoms of MALS.

Doppler sonography is the investigation of choice for diagnosing MALS. However, the gold standard method is conventional angiography performed during both inspiration and expiration. Other investigations used are Gastric tonometry, Mesenteric angiography, CT angiography or MR angiography. Currently, MDCT is widely employed to diagnose MALS with high accuracy because of production of thin sections and 3D reformatted images, which enables visualisation of focal narrowing in the proximal celiac axis causing hooked appearance. This feature allows differentiating this condition from other causes of celiac artery stenosis such as atherosclerosis. CTA also reveals other features such as Post-stenotic dilation and collateral vessels [4].

The treatment of MALS is subject to debate. However, in middle-aged patients with significant symptoms in addition to marked post-stenotic dilatation and collateral vessels on imaging studies, surgery is regarded as the primary modality of treatment. Preferred surgical procedures performed are open or laparoscopic division of the celiac ganglion causing destruction and/or blockage. Recent advances in treatment include imaging guided alcoholic ablation of the celiac ganglion [5].

Written informed patient consent for publication has been obtained.