Intramesenteric dynamic contrast pediatric MR lymphangiography: initial experience and comparison with intranodal and intrahepatic MR lymphangiography.

OBJECTIVES: To report on our initial experience with intramesenteric (IM) dynamic contrast magnetic resonance lymphangiography (DCMRL) for evaluation of the lymphatics in patients with concern for mesenteric lymphatic flow disorders and to compare IM-DCMRL with intrahepatic (IH) and intranodal (IN) DCMRL. METHODS: This is a retrospective review of imaging findings in 15 consecutive patients who presented with protein losing enteropathy (PLE) and/or ascites undergoing IM-DCMRL, IH-DCMRL, and IN-DCMRL. The IM-DCMRL technique involves the injection of a gadolinium contrast agent into the mesenteric lymphatic ducts or lymph nodes followed by imaging of the abdomen and chest with dynamic time-resolved MR lymphangiography. RESULTS: IM-DCMRL was successfully performed in 14/15 (93%) of the patients. When comparing IN-DCMRL with IM-DCMRL, there was a significant difference in the visualization of dermal backflow (p = 0.014), duodenal perfusion (p = 0.003), duodenal leak (p = 0.014), and peritoneal leak (p = 0.003). IM-DCMRL demonstrated peritoneal leak in 7 patients in contrast to IH-DCMRL which demonstrated leak in 4 patients and IN-DCMRL which did not demonstrate any peritoneal leaks. Duodenal leaks were seen by IH-DCMRL in 9 patients versus 5 with IM-DCMRL and none with IN-DCMRL. In one patient with congenital PLE, the three modalities showed different disconnected flow patterns with duodenal leak only seen by IM-DCMRL. There were no short-term complications from the procedures. CONCLUSIONS: IM-DCMRL is a feasible imaging technique for evaluation of the mesenteric lymphatics. In certain mesenteric lymphatic flow abnormalities, such as PLE and ascites, this imaging may be helpful for diagnosis and the planning of interventions and warrants further studies. KEY POINTS: • Intramesenteric dynamic contrast magnetic resonance lymphangiography (IM-DCMRL) is a new imaging technique to evaluate mesenteric lymphatic flow disorders such as ascites. • IM-DCMRL is able to image lymphatic leaks in patients with ascites and protein losing enteropathy not seen with intranodal (IN-DCMRL) imaging.