A robot-assisted system developed at the University of Twente promises to make medical procedures that use needles more precise. The system allows flexible needles to be steered in real time to their target, which negates issues with tissue and organs deforming from the contact pressure or from any unforeseen obstacles that lie between the needle and its target.

Needles inserted even a few millimeters away from their target can cause problems with both diagnosis and therapy. Placed wrongly, they could render many treatments ineffective or even result in the wrong section of a liver or lung or some other organ getting biopsied in a search for possible tumors.

The needle can change direction because it has a bevel-shaped asymmetric tip. This tip causes a natural bend in the needle, so to steer it as it travels deeper into the flesh, you need only rotate it. The researchers developed an algorithm that allows a robot arm to track and control the needle's position using ultrasound imaging, allowing it to attain sub-millimeter levels of accuracy.

They also created a shared control mechanism that allows medical professionals to retain direct control, but that still uses the robot to augment the process. The robotic system provides visual and haptic (vibrational) feedback for guidance. It has been integrated into a clinically-approved device called an automated breast volume scanner, which is typically used to perform 3D ultrasounds of women's breasts to screen for cancer.

Although the technology is here now, we won't see it in hospitals any time soon. The researchers believe the system is another few years from starting clinical trials in humans, which marks it as several years or more from broader real-world practice.

Much of the research was conducted as part of University of Twente student Momen Abayazid's doctorate. He defended his doctoral thesis this week.

Source: University of Twente