First experience with a new optical target device for CT-guided punctures.

Purpose: To evaluate the prototype of a new optical target device for CT-gu ided punctures and interventions. Methods: An optical target device for CT- guided punctures was applied in 24 interventions. The system consists of a laser target device mounted on a stand. The biopsy needle is adjusted accor ding the course of a laserbeam. The targetangle has to be adjusted on the l aser unit. The laser carrier can be moved along an 90 degrees-angled rail, allowing punctures from any angle in plane. Furthermore, angulation in the z-plane is possible, supporting interventions with gantry tilt. Size and de pth of the target lesions, the planned and the actual angle of the inserted needle, the numbers of corrections of the needle position, and the time re quired for the puncture were evaluated. The user rated the benefit of the s ystem and the ease of the application. Results: All 24 interventions were c arried out successfully. The mean difference between the planned and the ac tual angle od the needle was 1.3 degrees (SD: 0.7 degrees). The system was considered as easy to handle and as a valuable aid. Conclusions: The laser target device is a simple navigation system which allows accurate positioni ng of a needle. Requiring an acceptable low preparation time, it easily can be integrated into the procedure.