The diagnosis of MALS is one of exclusion, as many healthy patients demonstrate some degree of celiac artery compression in the absence of symptoms.

Once suspected, screening for MALS can be done with ultrasonography and confirmed with computed tomography (CT) or magnetic resonance (MR) angiography.

Treatment is generally surgical, the mainstay being open or laparoscopic division, or separation, of the median arcuate ligament combined with removal of the celiac ganglia.

Poorer responses to treatment tend to occur in patients of older age, those with a psychiatric condition or who use alcohol, have abdominal pain unrelated to meals, or who have not experienced weight loss.

Patients with MALS reportedly experience abdominal pain, particularly in the epigastrium, which may be associated with eating and which may result in anorexia and weight loss.

This fibrous arch forms the anterior aspect of the aortic hiatus, through which the aorta, thoracic duct, and azygos vein pass.

[5] One proposes that compression of the celiac artery causes ischemia, or decreased blood flow, to abdominal organs, leading to pain.

[5] A reasonable screening test for patients with suspected MALS is duplex ultrasonography to measure blood flow through the celiac artery.

[5] The mainstay of treatment involves open or laparoscopic surgery approaches to divide, or separate, the median arcuate ligament to relieve the compression of the celiac artery.

[5] According to Duncan,[5] the largest and more relevant late outcomes data come from a study of 51 patients who underwent open surgical treatment for MALS, 44 of whom were available for long-term follow-up at an average of nine years following therapy.

In this study, predictors of favorable outcome included:[citation needed] It is estimated that in 10–24% of normal, asymptomatic individuals the median arcuate ligament crosses in front of (anterior to) the celiac artery, causing some degree of compression.