Median arcuate ligament syndrome – imaging presentation and interdisciplinary management

Introduction

The median arcuate ligament syndrome (MALS) is a rare disease entity. The prevalence of MALS is not known. It is more prevalent in women (4:1 ratio) between the ages of 30 to 50 years and in patients with a lean body habitus (Kim EN et al. JAMA Surg 2016; 151: 471 – 7). Diagnostic workup is particularly challenging and the therapeutic management, if indicated, requires close collaboration between a laparoscopically skilled surgeon and the interventional radiologist. While morphologic compression of the celiac trunk can be frequently observed on sagittal CT angiograms, only rarely this compression leads to clinical symptoms. Mere morphological compression is nsot an indication for either interventional or surgical treatment. In case of morphological compression of the median arcuate ligament observed on cross-sectional imaging, two clinical entities however require a dedicated work-up, both can be summarized under MALS: Dunbar syndrome describes postprandial pain attributed to reduced blood flow to the intestine due to the functional stenosis of the celiac trunk induced by compression of the median arcuate ligament (Kim EN et al. JAMA Surg 2016; 151: 471 – 7). On the other hand, functional stenosis of the celiac trunk can lead to increased perfusion of the pancreatico-duodenal arcades with reversed flow in the gastroduodenal artery and sometimes also the common hepatic artery, referred to as Sutton syndrome (Corey M et al. J Vasc Surg 2016; 64: 1734 – 1740). As the pancreatico-duodenal arcades are not laid out for such an increased perfusion, vessels may become fragile with increased risk of bleeding and formation of aneurysms (Chivot C et al. Eur J Vasc Endovasc Surg 2016; 51: 295 – 301). This life-threatening condition requires a dedicated angiographic workup and interdisciplinary treatment approach, targeting both the degraded vasculature as well as the underlying ligamentous compression of the celiac trunk. Based on six challenging cases the clinical presentation, diagnostic workup and therapeutic management of MALS are presented.