Laser Target System in Combination with an Aiming Device for Percutaneous CT-Guided Interventions – An Accuracy Study

Abstract

To evaluate the targeting accuracy of laser-guided punctures in combination with an aiming device for computed tomography (CT) interventions during in vitro experiments. MATERIALS ANDMETHODS: A total of 600 CT-guided punctures were performed using a laser target system, half of them with the additional help of an aiming device. Conically shaped targets in a plexiglass phantom were punctured. The planning CT data sets were acquired with 1.25, 2.5 and 5mm slice thickness. Needle placement accuracy, as well as procedural time, wasassessed. The Euclidean (ED) and normal distances (ND) were calculated at the target point. Using the aiming device, the accomplished mean ND at the target for the 1.25, 2.5 and 5mm slice thickness was 1.76mm (SD±0.92), 2.09mm (SD±1.06) and 1.93mm (SD±1.38), respectively. Without aiming device, the corresponding results were 2.55mm (SD±1.42), 2.7mm (SD±1.43) and 2.31mm (SD±1.64). At a slice thickness of 1.25mm and 2.5mm, punctures with the aiming device were significantly more accurate for both the ED and ND as compared to the punctures without aiming device (p<0.001).The mean time required to complete the procedure, including image acquisition, trajectory planning, the placement of 10 needles, and the control-CT scan was 24.8min without and 29.8min with the aiming device. The additional use of the aiming device in combination with the commercially available laser guidance system significantly increased the level of accuracy during this in vitro experiment compared to freehand passes.