Accuracy of navigated percutaneous needle insertions

A navigation system for radiological interventions (CAS-One IR, CAScination, Bern) has been used to evaluate three different needle insertion methods on a non-rigid liver phantom. The insertion methods under investigation include: navigated free-hand needle insertion, aiming device-based insertion with active depth control and aiming device-based needle insertion with passive depth control. For each method a series of 25 punctures was performed and assessed by computing residual error (RE) given by the system and target positioning error (TPE) given from control CT scans.