Utilization of an aiming device in combination with laser guidance during interventional CT procedures can increase targeting accuracy.
Laser guidance has previously been shown to improve needle placement during percutaneous interventions, but this procedure has drawbacks, experts involved in a new study published in Academic Radiology recently explained.
Even with laser guidance, needles must be inserted manually and have to be illuminated continuously to keep clinicians from losing their mark. If a needle is not supported properly, its path could deviate during verification scans, resulting in the need for additional sequences and radiation exposure.
An aiming device presents a potential solution for the scenario, corresponding author of the new study Reto Bale, MD, with the Department of Radiology at Medical University Innsbruck in Austria, and co-authors suggested.
“Additional support could be provided by a rigid aiming device to maintain the needle's steady position within the laser beam. In addition, a needle holder already aligned at the target allows needle insertion at a higher velocity, which may enhance position accuracy and reduce tissue damage,” the experts explained.
Bale and colleagues recently tested the effectiveness, using an Atlas aiming device. They compared its accuracy by conducting procedures with and without the use of targeting support during 600 CT-guided punctures on a plexiglass phantom. The team acquired planning CT data sets with 1.25, 2.5 and 5 mm slice thickness to assess needle accuracy and how use of the device affected procedural times. Euclidean (ED) and normal distances (ND) were calculated at the target point.
With the device, mean ND at the target for the 1.25, 2.5 and 5 mm slice thickness was 1.76 mm, 2.09 mm and 1.93 mm. In comparison, freehand insertion results were 2.55 mm, 2.7 mm and 2.31 mm. For both the ED and ND, the accuracy was significantly improved with the device at a slice thickness of 1.25 mm and 2.5 mm.
Use of the device did result in a slight uptick in procedure times, increasing from 24.8 minutes without it to 29.8 minutes with it.
Since aiming devices stabilize needles, they could be especially beneficial in reaching superficial or bone lesions and could also be useful in targeting deep lesions, the authors suggested.
The team noted that their results “indicate a clear, statistically significant superiority” in accuracy with the utilization of an aiming device, adding that it should be technically feasible via laser guidance systems already in clinical use.
The study abstract is available here.