Robotics Surgery: Robots in the Operating Room : Part 2

by Food and Drug Administration (FDA)

(Page 2 of 2)

In preparing for robotics surgery, about a week before the actual procedure the doctor places three small titanium pins in the patient's femur. Robodoc will later use these as markers to locate the precise point to begin drilling. Next, three-dimensional pictures of the patient's femur are taken using a CT scanner or MRI system.

These pictures are then fed into a computer along with other patient data the doctor uses to select the best implant for that patient. Using this information, along with already loaded data that defines the specific size and shape of the implant, the surgeon programs the robot to make specific cuts in the patient's femur. These cuts mill out a cavity matching the shape and size of the implant. During surgery, the doctor removes the hip socket and top of the femur, immobilizes the bone in a "fixator," aligns Robodoc to the three pins, and, if all information and alignment is correct, hits the "start" button, which tells the robot to begin drilling.

Robodoc, using its high-speed drill, then cuts the hole down the length of the femur. The resulting cavity almost exactly matches the size and shape of the implant. The cavity Robodoc creates is up to 10 times more precise than that created by surgeons with hammers and broaches, according to a report in the journal Clinical Orthopedics.

"The robot can cut with far greater accuracy than any human hand. We looked at radiographs taken just before patients left the hospital and, over the implant's surface, we didn't see any gaps, unlike with hand tools," Bargar says.

Now that 10 surgeries are done, Bargar says, Integrated Surgical Systems, the company formed to develop Robodoc, plans to ask FDA for permission to conduct full-scale clinical trials at five or six medical centers around the country, including Shadyside Hospital in Pittsburgh and New England Baptist Hospital in Boston. The results of the clinical trials will be compared with results of surgeries using traditional methods.

Brain Cancer Surgery

Robodoc isn't the only robot used in the operating room. Neurosurgeon James Drake at the Hospital for Sick Children in Toronto uses a robotics device to remove previously inoperable brain tumors in seriously ill children, as well as in epilepsy and vascular malformation surgeries.

He and the three other neurosurgeons on the hospital's staff use the ISG Viewing Wand — an imaging computer and a jointed arm with a probe attached to the end. The device, currently under FDA review, "is calibrated like a robot but it doesn't move under any of its own power," Drake says.

In preparing for surgery using the device, the doctor takes CT scans or MRI images of the patient's brain. These images, which outline the tumor boundaries, are then fed into a computer, which reformats the pictures into a "three- dimensional picture that looks just like the patient," he says. The robot arm holds the 5-inch to 10-inch probe. With the 3- D pictures on a computer screen during the operation, the surgeon directs the robot arm to slide the probe into the patient's brain. The position of the arm in space is relayed to the computer, which "shows you on the reconstructed images [on the computer screen] exactly where you are in the brain. "Without the ISG Viewing Wand, some of these kids would not have been operated on or the surgery would not have been as successful in removing tumors," Drake says.

Prostate and Abdominal Surgeries

Prostate surgery using robots is being tested in Great Britain although this technology has not yet been tried in the United States.

Brian Davies, senior lecturer in the Department of Mechanical Engineering's Robotics Center at London's Imperial College, is working with the Institute of Urology to test a computer-driven robotics device that removes diseased prostate glands.

It has a special-purpose framework consisting of a tiny ring that rotates 360 degrees. The ring holds a small sliding carriage that carries an endoscope (an instrument for viewing inside a hollow organ) and cutter.

The entire system is attached to a thin, flexible catheter, which is motorized and computer controlled. "We preoperatively image the size of the gland using transrectal [through the rectum] ultrasound and then program into the computer control system the size of the gland," Davies says. The computer system automatically generates the shape and sequence of cuts.

Watching the progress on a nearby video monitor, the surgeon inserts the catheter with instruments into the patient's penis until the computerized system reaches the correct place.

At this point, the surgeon turns the operation over to the robot, which performs the necessary preprogrammed cuts, according to Davies.

So far, the procedure has been used on only five patients, Davies says, and it's too early to draw any conclusions about the device's safety.

In addition to the prostate device, the Robotics Center is designing rehabilitative robots, as well as those to machine the ends of bones for prosthetic implants in knee surgery. Another area in which robotics may soon take on a role is that of laparoscopy used in surgery.

To perform laparoscopy, the surgeon threads a fiber-optic cable that holds a tiny video camera and cutting tool on the end through a small incision in the patient's abdomen. The surgeon monitors the operation by images on the monitor. The video camera is usually operated by an assistant. Though these procedures are less traumatic for the patient than traditional surgery with its larger incisions, they are more difficult for the surgeon.

Some U.S. companies are working on devices that would make these procedures easier for the surgeon. For example, IBM Corp. is currently developing a robot to move and manipulate the tiny camera and cutting tool. The camera would be guided by the surgeon's voice.

While it may be some time before patients see something as friendly as R2-D2, the famous "Star Wars" movie robot, in the operating room, less dramatic-looking robots have begun to assist surgeons with a good number of surgical procedures.

About the Author

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.