Abstract
Median arcuate ligament syndrome (MALS) is a rare vascular disorder. We report the case of a 72-year-old man with MALS who was found to have an anomalous right inferior phrenic artery originating from the celiac artery (CA), which was not detected on preoperative computed tomography angiography. During laparoscopic decompression, this vessel was encountered unexpectedly. A temporary clamping test was performed, confirming no diaphragmatic or hepatic ischemia, after which the vessel was safely ligated. The CA was then fully decompressed. Postoperatively, the patient's symptoms resolved completely. This case underscores that significant vascular anomalies may only be revealed intraoperatively. The described clamping technique provides a simple and safe method for real-time functional assessment, aiding critical surgical decisions when managing unforeseen anatomical variations.