From the Guidelines
The workup for Median Arcuate Ligament Syndrome (MALS) should begin with a thorough clinical evaluation focusing on postprandial abdominal pain, weight loss, and epigastric bruits, followed by imaging studies such as CT angiography or MR angiography with inspiration and expiration phases to visualize the characteristic "hooked" appearance of the celiac artery and measure the degree of stenosis, as recommended by the most recent guidelines 1.
Key Components of the Workup
- Initial diagnostic testing should include duplex ultrasound of the celiac artery to assess for flow abnormalities during respiration 1
- CT angiography or MR angiography with inspiration and expiration phases is recommended to visualize the characteristic "hooked" appearance of the celiac artery and measure the degree of stenosis 1
- Gastric tonometry during exercise can help evaluate for mesenteric ischemia
- Celiac plexus block may serve as both diagnostic and therapeutic, with temporary pain relief suggesting MALS
Exclusion of Other Causes
- Comprehensive laboratory tests should be performed to exclude other causes of abdominal pain, including complete blood count, comprehensive metabolic panel, lipase, and amylase 1
- Gastrointestinal endoscopy is important to rule out other pathologies like peptic ulcer disease or gastritis
Multidisciplinary Approach
- A multidisciplinary approach involving vascular surgeons, gastroenterologists, and pain specialists is essential for accurate diagnosis, as MALS remains a diagnosis of exclusion after other common causes of chronic abdominal pain have been ruled out 1
- Psychological evaluation may also be beneficial as chronic pain can have significant psychological components
Treatment Options
- Surgical release of the MAL is beneficial and has been associated with symptomatic relief in 84.6% of patients, with subsequent reconstruction of the celiac artery may be necessary to provide complete symptomatic relief 1
From the Research
Diagnostic Workup for Median Arcuate Ligament Syndrome (MALS)
The diagnostic workup for MALS typically involves a combination of imaging modalities to demonstrate celiac axis compression, including:
- Doppler ultrasound 2, 3, 4
- Computed tomography (CT) angiography 2, 5, 6
- Magnetic resonance (MR) angiography 2, 6
- Mesenteric arteriography 3, 4, 6
- Gastric exercise tonometry 3, 6
Key Considerations
- MALS is a diagnosis of exclusion, and other causes of symptoms must be ruled out 2, 3, 5, 6
- The diagnosis of MALS can be challenging due to the variable symptom severity and unpredictable response to treatment 2, 3
- A suggested diagnostic workup and treatment algorithm have been proposed, but no consensus agreement exists on diagnostic criteria 3
Treatment Options
- Surgical management involves decompression of the median arcuate ligament's constriction of the celiac artery, which can be performed using:
- Nonoperative management may result in worse outcomes, and surgical intervention can provide effective symptom relief 3
- Angioplasty and stenting may be used in recalcitrant cases, but do not address the underlying extrinsic compression resulting in symptoms 2, 6