Novel System Improves Accuracy of Needle Placement for Ablation Procedures

This study demonstrates improved accuracy in needle placement for ablation procedures using a novel 3D ultrasound trajectory system. Ultrasound guidance can be difficult and require years of experience to master. In addition it does not provide a real time trajectory to the target. This system creates an advanced, real-time stereoscopic image when added to standard ultrasound creating a 3D guided approach to placement. Users with experience ranging from novice to expert made microwave needle antenna placements into a target both with and without advanced guidance. We hypothesized increased accuracy with the guidance system for needle placement at all angles of approach regardless of experience.
Methods. 180 targets of 6-8mm size were created 3cm deep to the surface in agar gel. An InVision guidance system (InnerOptic, Chapel Hill, NC) was attached to the ultrasound probe and microwave needle antenna of a B-K Pro Focus 2202 (B-K Medical, Denmark) with surgical T probe (#8659). The 3D display for advanced targeting guidance was viewed through passive stereo glasses on a 42 inch plasma stereoscopic monitor. A 13 gauge 22cm surgical microwave needle antenna (Valley Lab, Boulder, CO) was used for all procedures. A novice, amateur, and expert made placements which were randomized between use of enhanced image guidance versus standard ultrasound and three angles of approach relative to the ultrasound plane: 0, 45 and 90 degrees. Users could not alter the needle course once an angle of approach was chosen. Accuracy data was collected by ultrasound confirmation in two planes. Descriptive statistics comparing guided versus non-guided were calculated using chi-square test.
Results. Users made 10 placements each for the three angles with and without advanced image guidance. For all users at all angles the accuracy improved significantly when using the guidance system: 40% to 90% (p

Session: Podium Presentation

Program Number: S126