Intraoperative trans-esophageal echographic evaluation of the celiac artery flow after arcuate ligament resection in a case of Dunbar Syndrome. A case report

Dunbar Syndrome (DS), also known as Median Arcuate Ligament (MAL) syndrome, is a rare disease in which the celiac trunk is compressed by a fibrous attachment at the diaphragmatic crura causing abdominal angina with a large spectrum of symptoms including nausea, vomiting, weight loss, and postprandial epigastric pain. First anatomically described by Lipshutz in 1917 [1], this syndrome has a prevalence of 2/100,000 patients, women being more affected than men (3:1 ratio). DS usually involves young adults aged between 18 and 30 years. The traditional onset of the disease includes weight loss, nausea with vomiting, diarrhea and epigastric pain [2]. The MAL is a band of fibrous tissue that surrounds the aortic hiatus which can predispose to DS in case of higher origin or lower insertion on the diaphragm. This finding is significant in a small subset of patients, leading to compression of the celiac trunk during expiration, and relief during deep breath inspiration. The pathophysiologic mechanism of this rare disease still remain unclear, but the most widely accepted theory suggests the post prandial increased demand for blood flow by the gut through a compressed celiac artery ultimately leads to transitory intestinal ischemia and epigastric pain. Possibly, chronic pressure on the celiac ganglion by the MAL can be associated with the development of neuropathic pain due to an overstimulation and irritation of sympathetic pain fibers triggering epigas visualization of the shape of the transducer through the stomach wall over the celiac trunk and the MAL. Color Doppler Ultrasounds (US) has shown a pivotal role for the diagnosis and follow-up of DS allowing the examiner to perform a dynamic study of the involved anatomical site. In previous case reports [3], echography has been used to confirm the return to normal flow on the celiac trunk after laparoscopic resection of the MAL, but never by means of trans-esophageal probe and intra-operatively. With this case report we propose a novel application of the trans-esophageal echography not only as a diagnostic tool, but also as a functional guide during the surgical treatment of the DS and as a way to confirm the successful decompression of the celiac artery at the end of the operation. During the surgery, the TEE probe was left in the same position in standby mode in order not to overheat or damage the gastric mucosa. At the end of the surgical section of the MAL the PSV of the celiac trunk was re-evaluated showing significant drop now oscillating with the respiratory cycle between 76 and 98 cm/s (Figure 4). The patient was then awakened from anaesthesia and after a brief postoperative observation and monitoring, was discharged to the ward. The postoperative period was uneventful, food intake was started the first day after surgery with no pain recurrence, and the patient was discharged from the Hospital on the third postoperative day.