Purpose: This study aimed to assess whether computed tomography (CT) findings can be used to predict blood flow from the superior mesenteric artery (SMA) to the celiac artery (CA) region in patients with median arcuate ligament syndrome (MALS).

Materials and methods: Two radiologists who reviewed 1,290 conventional SMA angiograms and CT scans identified 36 patients with MALS. MALS was classified by their blood flow angiography findings as type A (CA region not or barely visualized) and type B (CA region clearly visualized). The association between patient age, sex, post-stenotic dilatation ratio of the celiac axis, maximum diameter of the pancreaticoduodenal arcade (PDA), and MALS classification based on SMA angiography was assessed.

Results: Of 36 MALS patients, 17 had MALS type A and 19 had MALS type B. The mean of the maximum diameter of the PDA in MALS type A was 1.6 ± 0.9 mm (SD) and 4.3 ± 1.3 mm in MALS type B. The post-stenotic dilatation ratio of the celiac axis was 2.4 ± 1.2 in MALS type A and 2.2 ± 1.4 in MALS type B. Only maximum diameter of the PDA was a predictor of MALS type B (odds ratio, 15.7; 95% confidence interval, 2.3–108.1).

Conclusion: The maximum diameter of the PDA on CT angiography can be used to predict the blood flow from the SMA to the CA region in patients with MALS.