RESUMEN
OBJECTIVE: To investigate the accuracy, efficiency and radiation dose of a novel laser navigation system (LNS) compared to those of free-handed punctures on computed tomography (CT). MATERIALS AND METHODS: Sixty punctures were performed using a phantom body to compare accuracy, timely effort, and radiation dose of the conventional free-handed procedure to those of the LNS-guided method. An additional 20 LNS-guided interventions were performed on another phantom to confirm accuracy. Ten patients subsequently underwent LNS-guided punctures. RESULTS: The phantom 1-LNS group showed a target point accuracy of 4.0 +/- 2.7 mm (freehand, 6.3 +/- 3.6 mm; p = 0.008), entrance point accuracy of 0.8 +/- 0.6 mm (freehand, 6.1 +/- 4.7 mm), needle angulation accuracy of 1.3 +/- 0.9degrees (freehand, 3.4 +/- 3.1degrees; p < 0.001), intervention time of 7.03 +/- 5.18 minutes (freehand, 8.38 +/- 4.09 minutes; p = 0.006), and 4.2 +/- 3.6 CT images (freehand, 7.9 +/- 5.1; p < 0.001). These results show significant improvement in 60 punctures compared to freehand. The phantom 2-LNS group showed a target point accuracy of 3.6 +/- 2.5 mm, entrance point accuracy of 1.4 +/- 2.0 mm, needle angulation accuracy of 1.0 +/- 1.2degrees, intervention time of 1.44 +/- 0.22 minutes, and 3.4 +/- 1.7 CT images. The LNS group achieved target point accuracy of 5.0 +/- 1.2 mm, entrance point accuracy of 2.0 +/- 1.5 mm, needle angulation accuracy of 1.5 +/- 0.3degrees, intervention time of 12.08 +/- 3.07 minutes, and used 5.7 +/- 1.6 CT-images for the first experience with patients. CONCLUSION: Laser navigation system improved accuracy, duration of intervention, and radiation dose of CT-guided interventions.