Abstract
PURPOSE: Median Arcuate Ligament Syndrome (MALS) is often underdiagnosed due to nonspecific symptoms. This study proposes a CT-based grading system that evaluate the association between grade and the incidence of celiac or superior mesenteric artery aneurysms. METHODS: From January 2021 to July 2023, patients exhibiting the characteristic hooked appearance on sagittal contrast-enhanced CT, indicative of MALS, were included in the study. An age- and sex-matched hypertension screening cohort was also recruited as a control group for comparison. They were classified into mild-to-moderate and severe stenosis groups based on a 50% stenosis threshold. Clinical data (biochemical markers, etc), and imaging parameters (SMA and CA diameters) were analyzed to assess their association with MALS severity and related complications. RESULTS: A total of 427 MALS patients and 427 age- and sex-matched controls were included (69.1% male; median age 59 years). Radiological assessments showed increased abdominal aorta and distal SMA diameters in the MALS group. Higher age (p = 0.002), alcohol consumption (p = 0.022), lower triglycerides (p = 0.004), and larger SMA diameter (p = 0.001) were associated with MALS severity. Our study revealed that while the incidence of severe complications in MALS patients does not correlate significantly with age(p = 0.064), it peaks in those aged 60-69 years(50.8%). CONCLUSION: Contrast-enhanced CT serves as a valuable tool for classifying the severity of MALS and assessing associated complications. MALS severity correlates with older age, alcohol consumption, lower triglyceride levels, and larger SMA diameter. These findings underscore the importance of integrated clinical, biochemical, and imaging assessment in improving diagnostic accuracy, risk stratification, and management of MALS.