Clifford Raabe Weiss MD, Presenter: Nothing to Disclose

Aravind Arepally MD, Abstract Co-Author: Nothing to Disclose

Parag Karmarkar MS, Abstract Co-Author: Nothing to Disclose

Ergin Atalar PhD, Abstract Co-Author: Nothing to Disclose

To determine the feasibility of real-time MR guided punctures of the Superior Mesenteric Vein (SMV) from the Inferior Vena Cava (IVC).

Ten IVC-SMV punctures were performed in a porcine model (n=6, 90-100 lbs). A novel active MR intravascular needle system, made to form a loopless antenna, was utilized for proper needle tracking and extra caval puncture. All imaging was performed solely under MR guidance in a 1.5 T MR scanner (CV/i, GE Medical Systems Waukesha, WI). The needle was introduced though a standard clinical 12 F sheath in the common femoral vein. Using a real-time FIESTA sequence (3.4ms TR, 1.2ms TE, 45º flip angle, 30cm FOV, 6-8 frames/sec) in combination with an interactive scan plane acquisition (i-Drive, GE), the needle was advanced into the IVC and guided to the level where the SMV is closest to the IVC. Using a fast SPGR sequence (6.0ms TR, 1.5ms TE, 60º flip angle, 35cm FOV, 1 frame/sec) providing a temporal resolution of 1 slice/second, and realtime FIESTA sequence, the needle system was guided through the IVC and into the SMV. The location of the distal tip of the needle in the SMV was then confirmed by FSE sequence with double inversion black blood (1904ms TR, 4.5ms TE, 36cm FOV). After confirmation, a portogram, using Gd-DTPA with concentration of 25%, was performed using a FSPGR (6ms TR, 1.3ms TE, 90º flip angle, no slice selection, 45 x 22.5cm FOV, 1.5 frames/sec).

Successful MR guided IVC-SMV punctures were performed in all ten of the procedures. Active tracking of the needle in the IVC was possible. The needle was fully visualized as it traversed the retroperitoneum and entered the SMV. Direct portogram was successfully performed in all punctures, confirming the entry of the needle into the portal venous system. All animals survived.

Using only MR guidance and a novel MR intravascular needle system we were able to successfully puncture the SMV from the IVC with direct visualization of the needle and all the retroperitoneal structures. This is the first stage in the creation of percutaneous MR guided meso-caval shunt.

A.A.: GE and genentech stockholder.

Weiss, C, Arepally, A, Karmarkar, P, Atalar, E, Real-time MR-guided Meso-Caval Puncture: Towards the Development of a Percutaneous MR-guided Mesocaval Shunt.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4406382.html