Researchers at Vanderbilt University announced last week that they developed a surgical robot with steerable needle equipped with wrists smaller than 2 mm thick for use during micro-laproscopic, or needlescopic, surgeries.
The device is designed to provide greater dexterity to the microscopic tools, something they currently lack. The new wrists would allow surgeon-operators to perform previously impossible procedures like precise resections and suturing as well as using needles in places like the nose, throat, ears and brain.
The steerable needles use telescoping tubes of nitinol, a “memory” metal regularly used in stents and other medical devices for its shape-retaining attributes. Each tube in the needle’s wrist has a different intrinsic curvature, allowing operators to rotate, extend and retract the tubes to navigate through the organic curves of patient’s bodies.
To decrease rigidity, researchers cut a series of tiny slots down one side of the tube to enable them to bend up to 90 degrees through the use of a small wire running along the inside of the tube. Once the wire tension is released, the wrist springs back to a straight position.
“The smaller you can make surgical instruments the better…as long as you can maintain an adequate degree of dexterity. In my experience, the smaller the instruments, the less post-operative pain patients experience and the faster they recover,” project consultant and Vanderbilt professor of urological surgery S. Duke Herrell said in a press release.
Currently, minimally invasive surgeries, even when assisted by robotic systems, generally require incisions ranging from 5 to 10 mm. Intuitive Surgical‘s (NSDQ:ISRG) da Vinci system requires an incision of either 5 or 8 mm to operate.
“Although it works very well for abdominal surgery, the da Vinci uses a wire-and-pulley system that is extremely difficult to miniaturize any further, so it won’t work in smaller spaces like the head and neck,” research head and Vanderbilt associate professor of mechanical engineering Robert Webster said in prepared remarks.
The nitinol-tube design allows the steerable needle to operate in areas that manual endoscopic instruments and other surgical robots currently cannot reach.
Researchers hope to test the device in transnasal surgeries to remove tumors in the pituitary gland and at the skull base. Previously, such operations generally required cutting large openings in the skull or face.
“It should be useful for a number of other operations as well,” said Webster. “We think once we give this tool to surgeons they will find all kinds of applications we haven’t thought of.”
Researchers on the team behind the device hope to have control software finished by the end of summer, and are currently looking for a commercial partner to lead the way for FDA approval of the device.
“Our best case scenario is that the system could be available to surgeons in 4 to 5 years,” Webster said.
