Robotic ultrasound-guided prostate intervention device: system description and results from phantom studies.

BACKGROUND We introduce the first robotic ultrasound-guided prostate intervention device and evaluate its safety, accuracy and repeatability. METHODS The robotic positioning system (RPS) determines a target's x, y and z axes. It is situated with a biplane ultrasound probe on a mobile horizontal platform. The integrated software acquires ultrasound images for three-dimensional (3D) modelling, coordinates target planning and directs the RPS. RESULTS The egg phantom evaluates the software's safety and workflow protocol. Two random targets are planned in each quadrant and biopsy needles are inserted. All were within three separate eggs. Metal wire tips are targeted and their distances from the biopsy needle tips are measured. With 20 wires, < 1 mm accuracy is obtained. Repeatability is demonstrated when previous positions are returned to with similar accuracy. CONCLUSION Our device demonstrates safety in a defined boundary with a repeatable accuracy of < 1 mm. It can be used for accurate prostate biopsy and treatment delivery.