Surgical Precision

Winter 2014

TEST TIME: Taylor tests a new robot that will  eliminate hand tremor in head-and-neck surgery.
TEST TIME: Taylor tests a new robot that will eliminate hand tremor in head-and-neck surgery. Photo by Will Kirk/

Robotic Minimally Invasive Surgery

Taylor has similarly helped develop robotic systems that are designed to be minimally invasive to reduce incisions, pain, blood loss, and scarring, while producing faster recoveries.
One example sits in the Swirnow Mock Operating Room set up in a glassed-in room at Hackerman Hall on the Homewood campus. Passersby can watch Johns Hopkins surgeons honing their incising, retracting, clamping, and suturing skills on a da Vinci Surgical System, a commercial robot manufactured by Intuitive Surgical, which employs several of Taylor’s IBM patents. Da Vinci allows complex and fine surgical operations to be performed laparoscopically with only a few tiny incisions.

Sometimes the surgeons in the mock operating room practice on animal tissue, other times they work on an array of colorful rubber dollops meant to represent the surgical targets the surgeons might encounter in an actual surgery. Taylor refers to the colorful practice environment as “Whoville.”

The robotic end of da Vinci has four arms that control various medical instruments. One arm positions a stereoscopic endoscope that allows the surgeon to see in three dimensions. The other three are fitted with medical tools as needed—scalpels, scissors, forceps, retractors, and the like. With finely pointed ends and fully articulated wrists, elbows, and shoulders, da Vinci’s instrumented arms come to resemble the forelegs of one of Maryland’s famed blue crabs—but with pincers much smaller than its crustacean counterpart.

The surgeon’s hands never touch the instruments. In fact, the surgeon sits across the operating room peering into a specially designed stereoscopic microscope that resembles an oversized View-Master of old. The images the surgeon sees are fed from an endoscope inside the patient and projected on high-definition screens, one screen per eye, that allow the surgeon to see in three dimensions and at 10-times magnification what the machine sees inside the body.

Directly below the viewfinder, the thumbs, index, and middle fingers of both the surgeon’s hands control electromechanical arms that sense the surgeon’s every move, conveying that information through the robot’s central processor to a second machine that performs the surgery at the other side of the room. The da Vinci essentially uses the motion of the control handles to control the action of the surgical tools held by the manipulator on the patient side of the robotic system. In robotics, this two-tiered system is known as telerobotics.
Taylor’s research interest in the da Vinci is in finding ways to exploit the fact that there is a computer between the surgeon and the surgeon’s instruments to create a human-machine partnership to improve surgery.

“The humans provide judgment and intelligence. The robots allow surgeons to transcend human physical limits, providing an order-of-magnitude greater sensitivity than even the best surgical hand can feel. Together, they make surgery less invasive, more precise, more consistent, and safer,” Taylor says.

Taylor and his colleagues have also explored similar ideas for other robotic systems. They have used a da Vinci master console to control one of their eye surgery robots with the idea of enabling an expert surgeon to assist a surgeon-in-training. Although the robots are mostly intended for use where both surgeons are at the same location, there are other possibilities on the horizon.

“Such robots will also enable advances in so-called telesurgery,” Handa says. “I might be able to assist a surgeon in South America by using a robot here in Baltimore, initiating and guiding movements half a world away.”

Another of Taylor’s minimally invasive surgical projects is a new collaboration with Vanderbilt University and Carnegie Mellon University funded by the National Science Foundation. In this effort Taylor and his collaborators—including his former postdoc, the principal investigator Nabil Simaan, now of Vanderbilt—will create a new paradigm in robotics known as “complementary situational awareness.” In this concept, the robot will take in sensory information as it performs surgery and use that information to build up a computer representation of the patient that can be used to help the surgeon perform the task. One of the robots for this project is based on a highly dexterous snake-like prototype that Simaan and Taylor developed at Johns Hopkins.