Imagine the best and most skilled surgeons in the world performing microsurgery. And then imagine there’s a new surgical tool in town to make even the best microsurgeons even better. Especially in microsurgery a steady hand is of utmost importance. But even the best surgeons have tiny, almost unnoticeable hand tremors. That’s human after all. Now researchers from Johns Hopkins have designed and tested a new surgical tool capable of correcting for these tiny hand movements.
The new device is named SMART, which stands for Smart Micromanipulation Aided Robotic-surgical Tool. It uses optical coherence tomography (OCT) as a distance sensor with computer-controlled piezoelectric motors to actively stabilize the tip of a surgical tool. With OCT imaging techniques it is possible to acquire imaging with a high resolution of under 10 microns. And as the physiological human trembling moves on the order of 50-100 microns, a high resolution imaging technique is required if you want to correct for it.
The researchers used fiber-optic based common path, swept source OCT, which uses one single fiber-optic cable to transmit and receive the near infrared light. This small fiber-optic cable was integrated into the front of a tool used in ophthalmic surgery. The SMART can operate at 500 hertz, compared to a human tremor frequency of 0-15 hertz. The ability to compensate for the hand tremors was tested in 5- and 30-second intervals. They used a viable chicken embryo and a phantom material to test it on.
In the coming years the SMART is planned to be taken from the lab the operating room. Hopefully this tool will not only enhance the hand movements of surgeons, but also take away a little bit of the trembling fear of patients who are planning to undergo microsurgery.
Study abstract in Optics Express: Active tremor cancellation by a “Smart” handheld vitreoretinal microsurgical tool using swept source optical coherence tomography