Background-rationale: To investigate whether interstitial injection of gadofosveset trisodium (Ablavar®, Lantheus Medical, North Billerica, MA) would be suitable for thoracic duct (TD) imaging in a pig model.

Methods and Results: Gadofosveset trisodium alone or premixed with 10% human serum albumin (HSA) was administered intradermally in the extremities of pigs at varying doses to visualize the TD by MRI. Two blinded readers evaluated MRIs for TD visibility. The inter-observer variability for all MR imaging sessions was assessed using the Spearman rank correlation test. MR lymphography using gadofosveset trisodium premixed with HSA yielded superior visualization of the TD compared to gadofosveset trisodium alone, with a high inter-observer agreement (correlation coefficient of 0.88 (p=0.00000115)).

Conclusions: We demonstrate that gadofosveset trisodium (premixed with 10%HSA) can be injected intradermally in order to perform MR lymphography of the thoracic duct. Since this agent is already FDA approved for MR imaging, the off-label use of it for imaging of the thoracic duct in humans is feasible, and the approach may prove to be beneficial for patients with TD abnormalities.