TIPS placement in swine, guided by electromagnetic real-time needle tip localization displayed on previously acquired 3-D CT.
OBJECTIVE
To determine the feasibility of guiding a transjugular intrahepatic portosystemic shunt (TIPS) procedure with an electromagnetic real-time needle 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 Colapinto needle. The real-time position and orientation of the needle tip was then displayed on previously acquired 3-D CT images which were registered with the five swine. Portal vein puncture was then attempted in all animals.


RESULTS
The computer calculated accuracy of the position sensor was on average 3 mm. Four of five portal vein punctures were successful. In the successes, only one or two attempts were necessary and success was achieved in minutes.


CONCLUSIONS
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.
Solomon
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SB
Division of Cardiovascular and Interventional Radiology, Department of Radiology, Johns Hopkins School of Medicine, 600 North Wolfe St., Baltimore, MD 21287, USA.
Magee
C
C
Acker
D E
DE
Venbrux
A C
AC
D000818:Animals; D055590:Electromagnetic Phenomena; D005240:Feasibility Studies; D007091:Image Processing, Computer-Assisted; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000295:instrumentation*; D015642:Radiology, Interventional / Q000295:instrumentation*; D013552:Swine; D014057:Tomography, X-Ray Computed