A recent experiment at Boston Children’s Hospital had bioengineers using self-navigating robot catheters to reach leaky valves inside pig hearts. The procedure they performed is known as a paravalvular aortic leak closure and is done to repair replacement heart valves that are leaking around their edges.
An autonomous robot navigated through the heart on its own without the need for guidance by a surgeon. Once at the scene, the surgeon was able to take over to finish a repair of the leaky valve. The surgeon then deployed a device from inside the catheter, called an occluder, to plug the leaky tissue surrounding the prosthetic valve. Researchers detected no signs of scratches, bruising, or other tissue damage.
Haptic Vision Makes It Possible
An integral part of this breakthrough surgery is the use of haptic vision. It’s a method of “seeing” through the sense of touch. The technology mimics the way insects and other creatures navigate in dark environments. The haptic vision system senses differences in heart tissue walls to find the way to the right location in the heart.
The catheter itself is an autonomous, concentric, telescopic tube robot. A motorized drive system rotates to telescopically extend tubes and control the shape of the catheter and its tip position.
Special optical touch sensors, along with AI, a pre-programmed anatomy lesson, and pre-operative scans inform the catheter where it is located and where to go next. A sensor attached near the bottom of the catheter recognizes the heart wall, senses the presence of blood, and detects the valve. It knows how strongly and frequently to exert pressure on tissue walls.
Benefits of Autonomous Robotic Surgery
One major benefit is that these surgical robots can perform complex procedures, and still allow surgeons to focus on difficult tasks. For patients, this minimally invasive procedure reduces the chance of trauma and infection. Self-guided robotic catheters also have an advantage over manually operated devices as patients are also not subjected to an average of 30 minutes of x-rays during the procedure.
A hurdle for clinical application is that technologies are developing faster than regulations. It can take several years for approval. Once approved, it might take a couple more years to be introduced.
But, experts are still impressed by the use of haptic vision to achieve autonomous control. They look forward to seeing other ways it may be used in the future. Other applications, such as spinal, vascular, and gastrointestinal procedures are being considered for haptic vision procedures.