BRACHYTHERAPY NEEDLE STEERING USING INTRATISSUE REAL-TIME ULTRASOUND 3D VISUALIZATION

Aim. To explore in a model experiment the capability of the developed software for 3D- ultrasound imaging of tumors in the pelvic tissue phantom to steer a brachytherapy needle using 6-axis robotic arm. Materials and methods. The experiment employed a six-axis robotic arm with a device for moving the needle, a phantom with a tumor model and ultrasound scanner with biplane transducer. Controlled by the developed software, the robotic arm automatically inserted the needle in the phantom. At all stages of inserting the needle, its position in the phantom was continuously tracked using data obtained by the ultrasonic transducer. Results The software was developed and tested for intra-tissue ultrasound imaging to steer a brachytherapy needle using US-scanner coupled with the robotic system providing 3D tumor modeling within the pelvic tissue phantom. In the course of the operation, the program corrects the existing model using current US images considering any shifting and swelling of the prostate. Conclusion. The model experiment proved the operational capability of the proposed method of 3D tumor modeling within the pelvic tissue phantom and tracking needle movement in the phantom in real time using US scanner coupled with a robotic system for brachytherapy. Further development of the software, providing ultrasound image processing and automatically correcting the brachytherapy needle trajectory, will complete preclinical studies of a robotic arm and warrant clinical trials.

brachytherapy, prostate tumor, phantom, robotic arm, ultrasound visualization, control algorithm