This study evaluates new applications using a novel navigation system with electromagnetic (EM) tracking in clinical routine.
The navigation system (iGuide CAPPA, CAS innovations, Erlangen, Germany) consists of a PC with dedicated navigation software, the AURORA tracking system (NDI, Waterloo Ontario, Canada) and needles equipped with small coils in their tips for EM navigation. After patient positioning a 3D C-arm data set of the spine region of interest is acquired. The images are reconstructed and the 3D data set is directly transferred to the navigation system. Image
loading and image to patient registration are performed automatically by the navigation system. For image acquisition a
C-arm system with DynaCT option (AXIOM Artis, Siemens Healthcare, Forchheim, Germany) was used. As new clinical applications we performed kyphoplasty for reconstruction of collapsed vertebrae. All interventions were carried out without any complication. After a single planning scan the radiologists were able to place the needle in the designated vertebra. During needle driving 2D imaging was performed just in a few cases for control reasons. The time between planning and final needle positioning was reduced in all cases compared to conventional methods. Moreover, the number of control scans could be markedly reduced. The deviation of the needle to
the planned target was less than 2 mm. The use of DynaCT images in combination with electromagnetic tracking-based navigation systems allows a precise needle positioning for kyphoplasty.
To ensure precise needle placement in soft tissue of a patient for e.g. biopsies, the intervention is normally carried
out image-guided. Whereas there are several imaging modalities such as computed tomography, magnetic resonance tomography, ultrasound, or C-arm X-ray systems with CT-option, navigation systems for such minimally invasive interventions are still quite rare. However, prototypes and also first commercial products of optical and electromagnetic tracking systems demonstrated excellent clinical results. Such systems provide a reduction of control scans, a reduction of intervention time, and an improved needle positioning accuracy specially for deep and double oblique access. Our novel navigation system CAPPA IRAD EMT with electromagnetic tracking for minimally invasive needle applications is connected to a C-arm imaging system with CT-option. The navigation system was investigated in clinical interventions by different physicians and with different clinical applications. First clinical results demonstrated a high accuracy during needle placement and a reduction of control scans.
Integrated solutions for navigation systems with CT, MR or US systems become more and more popular for
medical products. Such solutions improve the medical workflow, reduce hardware, space and costs requirements.
The purpose of our project was to develop a new electromagnetic navigation system for interventional radiology
which is integrated into C-arm CT systems. The application is focused on minimally invasive percutaneous
interventions performed under local anaesthesia. Together with a vacuum-based patient immobilization device
and newly developed navigation tools (needles, panels) we developed a safe and fully automatic navigation
system. The radiologist can directly start with navigated interventions after loading images without any prior
user interaction. The complete system is adapted to the requirements of the radiologist and to the clinical
workflow. For evaluation of the navigation system we performed different phantom studies and achieved an
average accuracy of better than 2.0 mm.