At Thomas Jefferson University Hospital a clinical trial is about to begin evaluating the performance of a robot designed to help urologists and radiation oncologists precisely place radioactive seeds into prostate tumor targets. Because brachytherapy seeds have to be individually inserted, human error becomes a significant problem, something a robot may soon prove to overcome on 14 subjects in the trial. The robot, called Euclidean, was designed in-house at Jefferson, and it sports 16 degrees of freedom (DOFs): 9 DOFs for positioning module and 7 DOFs for surgery module. Medgadget has contacted Jefferson radiation oncology investigators, and they kindly provided our readers with these images of the Euclidean robot.
From the official statement by Thomas Jefferson University Hospitals:
Prostate brachytherapy, which requires accurate insertion of some 60–120 radioactive seeds in very specific places in the prostate, involves a high degree of clinical skill and attention to detail, he says. “When performed with good quality, brachytherapy offers excellent cure rates compared to surgery, external radiation and proton therapy,” Dr. Dicker says. “However, poorly placed seeds may lead to urinary and rectal toxicities.”
Currently, physicians use a plastic or metal template with holes in which to insert 15-20 needles that contain radioactive seeds into the prostate gland. But because this grid is thin, it is difficult for a person guiding it to push it smoothly and straightly through glandular tissue. “The template forms a pivot point of sort, so the needles, which are unsupported, can twist ever so slightly,” he says. “Getting the seeds to the right place is very important because of the side effects that can occur from the radiation they emit.”
“With its motorized controls and imaging feedback, the robot can systemically place the seeds in a way we believe is more consistently accurate than a human can be,” says Yan Yu, PhD, Professor and Director of the Medical Physics Division in the Department of Radiation Oncology.
Dr. Yu led a team of medical physicists, engineers, radiation oncologists, radiologists and urologists who spent seven years developing the robotic system, which is called EUCLIDIAN. It incorporates high-resolution ultrasound image processing, dose planning using genetic algorithms, 3D visualization, smart needle rotation for reducing tissue deformation and prostate displacement, and force feedback from nano-sensors installed at various points on the robot. Needle insertion and seed delivery are fully automatic.
“The robot is controlled by a physician via a handheld controller and a computer interface,” he says. “It is capable of reverting to manual needle and seed insertion any time the physician desires.”
Press release: Robot to Have First Clinical Trial Test in Prostate Cancer Patients…
More about the system from a 2007 paper: Robot-Assisted Prostate Brachytherapy (.pdf)