Clinical Response to Celiac Plexus Block Confirms the Neurogenic Etiology of Median Arcuate Ligament Syndrome

Purpose: To evaluate the response of median arcuate ligament syndrome (MALS) symptoms, including postprandial pain, nausea, and vomiting, to celiac plexus block (CPB) and correlate the response with arterial anatomy. Materials and Methods: In a single-institution, retrospective cohort of clinically diagnosed MALS patients, 96 patients (female, 75; male, 21; mean age, 27 years) underwent 103 computed tomography.guided percutaneous CPB procedures. Imaging, procedural, and clinical reports were reviewed. Primary outcomes evaluated were technical success, change in self-reported pain score, and change in nausea and vomiting. Results: Computed tomography imaging before the procedure was available for 81 of 96 patients and demonstrated findings of celiac artery compression in 22 of 81 (27%) patients. Technical success was achieved in 102 of 103 cases. No major adverse events and 1 moderate adverse event were reported. The postprandial pain score decreased in 86 (84%) patients, and the mean score decreased from 6.3 to 0.9 points (P <.001). The prevalence of postprandial nausea decreased from 37.9% to 11.6% ( P <.001) and that of vomiting decreased from 15.5% to 4.9% (P = .019). No differences were noted in pain relief after CPB between patients with and without celiac artery compression (P = .745). Conclusions: In patients with a clinical diagnosis of MALS, a large majority reported pain relief and decreased gastrointestinal symptoms after CPB. Pain relief did not correlate with the presence of celiac arterial abnormalities. This supports neuropathy as the primary etiology of MALS and suggests that the absence of celiac stenosis should not be used as an exclusion criterion.