TIPS placement in swine, guided by electromagnetic real-time needle tip localization displayed on previously acquired 3-D CT

Purpose: To determine the feasibility of guiding a transjugular intrahepati c portosystemic shunt (TIPS) procedure with an electromagnetic real-time ne edle tip position sensor coupled to previously acquired 3-dimensional (3-D) computed tomography (CT) images. Methods: An electromagnetic position sensor was placed at the tip of a Cola pinto needle. The real-time position and orientation of the needle tip was then displayed on previously acquired 3-D CT images which were registered w ith the five swine. Portal vein puncture was then attempted in all animals. Results: The computer calculated accuracy of the position sensor was on ave rage 3 mm. Four of five portal vein punctures were successful. In the succe sses, only one or two attempts were necessary and success was achieved in m inutes. Conclusion: A real-time position sensor attached to the tip of a Colapinto needle and coupled to previously acquired 3-D CT images may potentially aid in entering the portal vein during the TIPS procedure.