V6-02: 3D-planned laserguided percutaneous access with the Uro Dyna-CT

V6-02: 3D-planned laserguided percutaneous access with the Uro Dyna-CT


Introductions and Objectives
The Uro Dyna-CT (Siemens Healthcare, Erlangen, Germany) has been installed in the endourological operating room in 2011. It provides a 3D-planning and laser-guiding puncture tool called the syngo iGuide®. We have evaluated this new tool in terms of accuracy and applicability for urologists in cases of complex punctures and present an ex-vivo feasibility study and the first clinical series with this technique.

The technique was evaluated using a well-established biological training model for percutaneous nephrolithotomy. Secondly, the technique was established in a clinical setting to perform complex punctures due to difficult anatomy or unclear ultrasound findings especially to gain access to the renal pelvis before percutaneous lithotomy.

We performed 16 punctures in 15 patients. 6 suprapubic catheters, 3 kidney tumor biopsies, 1 biopsy of a tumor in the minor pelvis and 6 percutaneous punctures of the calyceal system bevor stone treatment were performed. 14 of 16 punctures were successful. The time for the image acquisition and for the 3D rendering is less than 2 min. Median puncture time was 15.8 sec. Median planning time was 6.6min. Median fluoroscopy time was 1.46min. Radiation exposure caused by the procedure lead to a Dose area product of 5666μGym2 – 146 for fluoroscopy and 5520 for the Dyna-CT scan.

We believe this puncture technique is an excellent additional instrument allowing the urologist to handle complex punctures intuitively. The image acquisition leads to higher radiation doses than the standard fluoroscopy technique. However, it is in an acceptable range compared to alternative procedures such as CT-guided punctures with a multidetector computed tomography which is mainly used for complex cases.

Funding: This study was without any funding. For the development of the interventional table of the Uro Dyna-CT a cooperation contract existed.