Embarking on a Fantastic Voyage

Technology has made it possible for medical robots to evolve from the pages of science fiction novels to operating rooms.

Michael Barbella

promoting the movie accentuated the marvels of such a concept (and the casting of Raquel Welch as a scientist), but made a bold prediction as well:“In this world of ours, where going to the moon will soon be upon us, and where the most incredible things are happening all around us, someday, perhaps tomorrow, the fantastic events you will view can and will take place.”

Although microscopic-sized humans (and sexy female scientists) are still strictly science fiction fodder, the notion of treating medical conditions by actually entering the human body through tiny machines or robots is one that is no longer limited to the imagination. Advances in technology over the last four decades has enabled biomedical researchers to develop devices that can journey through the body to diagnose disease, deliver drugs or perform surgery.

The most clinically advanced devices have been developed for the digestive tract, which is easily accessible and can accommodate objects several centimeters in size. One of the pioneers of these gastrointestinal Magellans is Given Imaging, an Israeli firm that developed the PillCam, a capsule equipped with a tiny camera for recording images (via computer) of the GI tract and intestines.

Measuring 1.1 cm in diameter and 2.6 cm in length, the vitamin-sized device transmits pictures at a rate of two images per second and can generate more than 50,000 pictures over an eight-hour period. The device provides both doctors and patients with an alternative diagnostic tool, but there is some uncertainty about its ability to detect cancerous growths in the colon. Despite a study funded by Given Imaging concluding that the PillCam is less effective than standard colonoscopies at finding precancerous polyps and cancer, the PillCam has become widely used by physicians since its approval by the U.S. Food and Drug Administration (FDA) in 2001.

 

Technological advances over the last four decades have allowed doctors to operate on patients using robotic devices such as the da Vinci Surgical System, pictured above. Last year, 136,000 procedures were performed with the da Vinci System, up 60 percent from 2007. Photo courtesy of Intuitive Surgical, Inc.

Though the PillCam is technically not a robot—it relies on the body’s regular muscle contractions to force it through the intestine—its success has inspired research groups around the world to develop devices that can embark on voyages even more fantastic than those portrayed in science fiction films.

The CyberKnife Robotic Radiosurgery System has helped more than 60,000 patients worldwide fight tumors in various parts of their bodies since its introduction to the market in 1999. Photo courtesy of Accuracy Inc.

Robotics’ Recent Rise in the O.R.

Biological “submarines,” minuscule magnetic beads and self-assembling robotic surgeons certainly will make for a promising and exciting future in health care. But that future is still several years away at best.

As scientists work to fine tune the mechanical devices that may one day perform surgery or examine diseased tissue while inside the body, doctors are increasingly using robotic devices in the operating room to boost the accuracy of surgical procedures and improve patient outcomes.

“Robotic surgery really is just the natural progression or the next advancement of laparoscopic surgery,” said Stuart R. Geffner, M.D., director of Kidney and Pancreas Transplant Surgery for Saint Barnabas Health Care System’s Renal and Pancreas Transplant Division in Livingston, N.J.

While the concept of robotic surgery has existed for decades (at least on film, anyway), scientists and engineers have only recently been able to translate such a revolutionary idea from the silver screen to the operating room.

Doctors experimented sporadically with robotic devices in the 1980s, using machines with futuristic-sounding names like the PUMA 560 and the PROBOT (the latter was used to perform prostatic surgery). More of these machines began to pop up in the 1990s to help surgeons replace joints, reconnect fallopian tubes and perform heart bypass surgery.

It took until the turn of the millennium, however, for medical robots to be considered a viable (and safe) alternative to traditional surgery. In 2000, the FDA approved a robotic device called the da Vinci Surgical System for general laparoscopic surgery. Developed by Sunnyvale, Calif.-based Intuitive Surgical Inc., the da Vinci Surgical System (aptly named after the inventor of the first robot) consists of a small motorized cart with four arms. One of the arms holds a camera and the other three arms hold the surgical instruments necessary for surgery. A second unit, where the surgeon sits, is connected to the robot.

The da Vinci System gives surgeons a three-dimensional image of the work area through a viewfinder at the console. The image mirrors what physicians would see during traditional open surgeries, though some experts argue that the device actually enhances visualization.

“The da Vinci System offers surgeons obvious advantages in the areas of visualization, precision, dexterity, control and ergonomics through its 3-D vision system and EndoWrist instruments, as well as robotic-assisted and computer-enhanced technologies,” said Nora Distefano, market development specialist at Intuitive Surgical. “These advances are a distinct advantage for surgeons relative to existing laparoscopic and endoscopic technology.”

One of the key features of the da Vinci System that has helped make it a popular choice among surgeons is its ability to precisely mimic the operator’s motions. If, for example, a surgeon makes a pinching motion with his or her fingers, the instrument at the end of the machine’s “arm” will immediately pinch whatever object it is grasping.

Another unique feature of the da Vinci that its creators like to tout is the enhanced mobility of the

Proponents of robotic surgical devices claim the machines provide surgeons with an increased range of motion, improved dexterity, enhanced visualization and better access. Photo courtesy of Intuitive Surgical Inc.

device’s “wrists.” The system’s EndoWrists move 360 degrees, providing surgeons with better mobility than their own joints and making it easier for them to access and maneuver in smaller, more intricate areas of the body such as the bladder, prostate or kidney.

Geffner can attest to the accessibility and maneuverability of the da Vinci System. He used the device to perform the world’s first robotic-assisted kidney transplant shortly before Christmas last year.

“Laparoscopic instruments really only move in two planes. They move in and out and the jaws open and close, kind of like a scissors opens and closes. If you want to move the instrument an inch you have to move your hand an inch because it’s directly connected to the surgeon’s hand,” Geffner told Medical Product Outsourcing. “Robotic instruments are different. They wrist and turn the way your hands wrist and turn, so they move in three dimensions as opposed to the two dimensions laparoscopic instruments move in.

Robotic devices enable you to make very, very fine movements—finer movements than you could with your hand. They also remove the natural tremor that everyone has. So the combination of better visualization, the wristing, the 3-D movements of the instruments and the ability to make very fine movements with instruments made me realize we could now do certain things robotically that we could not do laparoscopically.”

Namely, the fine suturing when connecting blood vessels, which is a vital part of any kidney transplant. Though he had performed donor surgeries using the da Vinci System, Geffner said he practiced on a variety of materials and in an animal lab before trying the actual transplant procedure on a human patient. He also performed different parts of the procedure on patients before conducting the groundbreaking surgery on a diabetic woman at Saint Barnabas Medical Center.

Saint Barnabas is one of 916 hospitals throughout the nation that have the da Vinci System. Its prevalence can be attributed to the fact that Intuitive Surgical is the only manufacturer of a robotic-assisted medical device for use in minimally invasive soft-tissue surgery. Earlier this year, the company introduced the da Vinci Si Surgical System, an upgrade to its existing systems that features enhanced 3D high-definition resolution, an updated and simplified user interface to enhance operating room efficiency, an optional dual console that allows a second surgeon to assist during surgery or observe the procedure, and new ergonomic settings to the surgeon console.

Robotics Market Becoming More Crowded

The success of Intuitive Surgical’s da Vinci System over the last nine years has prompted other companies to design robotic or computer-assisted devices in the hopes of scoring similar victories in the market.

MAKO Surgical Corp. of Fort Lauderdale, Fla., has developed a robotic arm system that cuts down on recovery time and pain for patients undergoing knee resurfacing. The robotic arm resurfaces the knee while a stereo camera system updates the surgeon about the precise location of the diseased part of the knee. If the surgeon gets too close to healthy tissue, audio and visual alarms sound, and the robotic arm gives resistance so the doctor feels as if he or she has hit a wall.

MAKO, however, is not alone in its use of robotics in orthopedic surgery. CUREXO Technology Corporation of Fremont, Calif., has developed a device called the ROBODOC Surgical System, which allows doctors to pre-operatively plan their surgery in a 3-D virtual space and then execute the procedure exactly as planned in the operating room.

Pre-dating both MAKO and CUREXO’s products though, is the CyberKnife Robotic Radiosurgery System from Accuracy Inc. When it was approved by the FDA in 1999 for the treatment of head, neck and upper spine tumors, the device was the first and only commercially available radiosurgery system to combine image guidance and computer-controlled robotics, according to the Sunnyvale, Calif.-based firm.

In 2001 (the same year Intuitive Surgical received approval for its da Vinci System), the FDA approved CyberKnife Radiosurgery for the treatment of tumors anywhere in the body. Since then, the company has received FDA approval for systems that enable doctors to track, detect and treat tumors in the lung, liver, pancreas and spine.

CyberKnife Radiosurgery is not actually a knife, but rather a radiation tool that can destroy tumors and lesions without surgery, pain, anesthesia or long recovery times. “CyberKnife [Radiosurgery] is able to accomplish an equivalent and perhaps superior treatment because it is not limited by the ability to remove critical tissues,” said Gregg A. Dickerson, M.D., F.A.C.R., and specialist in CyberKnife Radiosurgery at Denver CyberKnife, a radiation therapy center based in Colorado’s capital city. “We can radiate them. It’s a very surgical modality rather than a radiation tool. It’s more of a surgical instrument.”

CyberKnife Radiosurgery uses image guidance software to track and continually adjust treatment for any patient or tumor movement, allowing patients to breathe normally and relax comfortably during treatment. Before treatment, the patient undergoes imaging procedures (usually CT scans) to determine the size, shape and location of their tumor.

After the scanning is completed, doctors transfer the image data to the system’s workstation, where they identify the exact size, shape and location of the tumor to be treated. Doctors also identify the surrounding healthy tissue to be spared doses of radiation.

Once a treatment plan is created, the patient lies on a table for radiation treatments that last between 30 and 90 minutes. The treatment typically involves the administration of between 100 and 200 radiation beams delivered from different directions, each lasting 10 to 15 seconds. Before each beam of radiation is delivered, the CyberKnife Radiosurgery system simultaneously takes X-ray images and compares them to the original CT scan. This image-guided approach continually tracks, detects and corrects for any movement of the patient and tumor during the treatment process.

“CyberKnife Radiosurgery costs 30 percent to 50 percent less than a dose of radiation delivered the traditional way,” Dickerson noted. “It is a tremendous cost savings to the health care system. And patients love it. They don’t have complications afterward, they go on with their lives.”