Tag: Soft Tissue Surgery

Having a surgeon with four arms is one of the advantages of the latest robotic technology now being studied at UT Southwestern Medical Center. Surgeons in the Southwestern Center for Minimally Invasive Surgery are studying the use of the latest technology a $1.4 million robot named da Vinci that, with a human at the controls, filters out tremor, enhances precision, offers three-dimensional imaging and eliminates the inverted manipulation of instruments usually required in laparoscopic procedures. The da Vinci can hold a camera in one hand while manipulating tiny laparoscopic surgical tools in its other hands. And it never tires like its human counterparts.

With a human surgeon at the controls, da Vinci filters out tremor, enhances precision, offers three-dimensional imaging and eliminates the inverted manipulation of instruments usually required in laparoscopic procedures. “The buzzword is ‘more precise than humanly possible.’ That’s the rationale for this technology,” said Dr. Daniel Scott, director of the Southwestern Center for Minimally Invasive Surgery and assistant professor of surgery at UT Southwestern. Although testing the four-armed robot is still ongoing, Dr. Scott said, “It seems advantageous from the standpoint of precision for some procedures.” Da Vinci is most popular in urology for that reason, especially for prostate operations. It’s also proved useful in surgeries on the esophagus and stomach. Researchers also are investigating its practicality for cardiac surgery such as coronary artery bypass grafting and valve replacement.

“It may well prove useful for general surgery procedures that have traditionally required open incisions like biliary reconstruction or pancreatic surgery,” Dr. Scott said. Laparoscopic surgeries, also called minimally invasive surgeries, are performed via several tiny holes rather than one long incision, reducing post-operative pain and recovery times. The method is increasingly popular.

The first robotic surgery, performed in 1995, relieved the need for an assistant to hold the camera during laparoscopic procedures. Da Vinci represents the next step, offering an instrument that actually performs the surgery based on controls handled by the surgeon. “It’s not difficult to learn,” Dr. Scott said. But he said it does take longer to set up, mostly to position the robot. It (the robot) is also expensive and cumbersome, which limits the operative field and can make it impractical for exploratory surgeries or surgeries that require surgeons to go in more than one area. “It takes choreography,” Dr. Scott explained.

Surgeons are still learning what its full potential is. But to be successful, Dr. Scott added, “It needs to supersede laparoscopy in terms of efficiency before the average surgeon is going to use it. But as this technology continues to evolve, no doubt it will be miniaturized. Smaller is going to be better.” Automation may also be in the future, with a doctor pointing to sections of tissue that need suturing and the robot doing it. That could potentially be integrated with computed tomography or magnetic resonance imaging scans, which could offer opportunities for dress rehearsals of procedures.

Another potential for the technology is for telerobotic surgery across distances — doctors in one city using the robot (to perform an operation) in another city. The first test of such a surgery was a successful trans-Atlantic gallbladder procedure, with the surgeon in New York and the patient in France. “It certainly could have applications for rural surgery or mentoring surgeons in the community on new procedures,” Dr. Scott said. “There are big permutations for the future of surgery, and that’s why we need to be leaders in this field as a medical school and as a center dedicated to minimally invasive surgery,” he said. “We have a strong track record of embracing robotics and research into this new type of technology here, and we look forward to continuing those activities with this new acquisition.”

Science Daily
February 28, 2006

Original web page at Science Daily

Researchers said Friday they are ready to launch a late-stage trial of vertebroplasty, a procedure in which a prosthetic vertebra is created by injecting plastic cement into the interior of a vertebra fractured by osteoporosis. The Mayo Clinic scientists conducting the Phase 3 study say the new technology improves function and relieves pain. “Vertebroplasty is a very safe and easy procedure that seems to work quite well,” David Kallmes, a Mayo Clinic interventional neuroradiologist who is doing the study, told United Press International. “The problem is that it has never been studied formally so we don’t know as much as we could about it. For instance, our retrospective study, which simply looked at past records, showed us that vertebroplasty also makes it easier for people to move, tie their shoes, mow their lawn, and live life fully. Before it was primarily thought of as a way to relieve pain,” he said.

Kallmes and his colleagues at the Mayo Clinic reviewed the records of 113 patients with spinal compression fractures treated with vertebroplasty at his institution. Almost all of them filled out the Roland-Morris Disability Questionnaire, which measures back pain and function, before the procedure, and a smaller number completed it afterwards at intervals up to one year. Prior to treatment, the average RDQ score was 18 on a scale of 23. That score dropped to 11 immediately after treatment and remained an 11 throughout the remainder of the study.

Kallmes said that the procedure was first developed for cancer patients about 10 years ago and is still widely used in Europe for cancer that has spread to the spine. He added that the Mayo Clinic uses it routinely for patients with multiple myeloma, but he and his colleagues found that the results were not as good for other types of cancer and nowhere near as good as the results they obtained for people with osteoporosis. According to Kallmes, vertebroplasty is performed on an outpatient basis and takes about 45 minutes. The patient lies flat for an hour or two afterwards to let the plastic cement harden fully, then is discharged. “The critical factor in this procedure is being able to see where the cement is going; that’s why it’s done in the radiology suite,” Kallmes explained. “If you are not well-trained and don’t have extremely good radiological equipment, the cement could get outside the vertebra and cause a blockage in the lungs or nerve injury and paralysis in the spinal cord. Usually our complication rate is 1 percent, and that’s from the rib fractures our multiple myeloma patients sustain from lying on the table for so long.”

Vance Watson, director of interventional radiology at Georgetown University Medical Center, told UPI that he uses vertebroplasty often and would welcome a clinical trial to explore the procedure’s boundaries. “It’s one of the few treatments we do where we improve people’s lives very quickly,” said Watson. “It’s very gratifying.” Watson remarked that his experience echoed the results of the Mayo study, with some patients reporting significant pain relief and others not much, but many saying they could function better as a result of the procedure. “A clinical trial would be a great help in these circumstances,” Watson remarked. “Retrospective data is enticing but is sometimes wrong. A prospective trial will prove how well the procedure works in a variety of patients, and give us data about its results we don’t currently have. This could lead to wider acceptance of vertebroplasty within the medical community, which could reduce the number of people with spinal compression fractures who must live with decreasing function and pain,” he said. Kallmes said that the trial, called INVEST (investigational vertebroplasty efficacy and safety), was underway around the world and involves about 300 people.

Science Daily
January 17, 2006

Original web page at Science Daily

Surgeons in France claim to have performed the world’s first face transplant, although not of a whole face. A 38-year-old woman severely disfigured in May by a dog attack received a “partial” triangular graft, consisting of the chin, lips and nose from a dead woman donor. “Today, the patient is in excellent general condition, and the graft is normal,” the surgical team, led by Jean-Michel Dubernard of the Edouard Herriot Hospital in Lyon, said in a statement. The operation was performed on Sunday 27 November at the University Hospital Centre (CHU) in Amiens, northern France, and the surgical team says further details of the procedure will be issued on 2 December.

The woman’s injuries were so severe that she could scarcely speak or chew. “This type of injury is extremely difficult, if not impossible, to repair by the usual maxillofacial surgical techniques,” the statement says. The breakthrough ends a race between teams in France, the US and Britain to perform the procedure first. “Now they’ve done it, I can breathe a sigh of relief,” says Peter Butler, head of a team hoping to perform a similar procedure, but with a whole face, at the Royal Free Hospital in London, UK. “Now, the pressure’s off, which is great.”

Butler says the woman’s graft will consist of skin, fat and muscle tissue, including veins, arteries and nerves. “Right now, she will be very swollen, and it will take 14 days or so for that to disappear,” he told a briefing in London. “Within 24 hours they’ll know if the graft will survive and, beyond that, failure is unusual.” Butler thinks that scarring will probably be minimal because the transplanted zone is a so-called “aesthetic unit”, meaning it attaches at natural junctions that should hide the scars. Surgeons will monitor the transplanted flap every 2 hours to ensure it’s perfused with blood. They will also monitor for tissue rejection, which will be a risk during the first two weeks. “If the blood vessels become blocked, there’s a risk of the operation failing,” says Iain Hutchison, consultant facial surgeon at St Bartholomew’s Hospital in London. “And there’s a medium-term risk of the immunosuppressive drugs failing to control rejection.”

Even if the graft takes, the patient will need to take immunosuppressive drugs for the rest of her life. This raises the risk of virally-induced cancers by decreasing the patient’s ability to keep dormant viruses in check. The patient and her family must also confront psychological consequences of the procedure, including possible crises of personal identity.”Facial appearance is very closely associated with an individual’s sense of personal identity, so the recipient must adapt to this new ‘identity’, as well as to other people’s responses to it,” says Stephen Wigmore, chair of the ethics committee of the British Transplantation Society. Likewise, families of the donor must adjust to the possibility that they may see a living person resembling their dead relative, although computer simulations suggest that a transplanted face will have a “hybrid” appearance in which the facial features of the donor are altered by the bone structure of the recipient.

Butler says his team is about to start screening potential patients for a whole facial transplant. But it would be 6 to 12 months at the earliest before he attempts the procedure, which must also be cleared by the ethics committee of the Royal Free Hospital. Other teams vying to perform the procedure are at the Cleveland Clinic Foundation in Ohio, and at the University of Louisville School of Medicine in Kentucky, both in the US. “This is an exciting development,” says John Barker, who leads the effort at the University of Louisville. “We will be following the outcome closely for the medical, psychological and ethical information that may be gained.”

New Scientist
December 20, 2005

Original web page at New Scientist

Just 8 centimetres long, the devices are designed to be slipped inside a patient’s abdomen through a tiny incision. Meet the robots that can perform surgery from within your own body. Their creators hope that the remote-controlled surgeons are a step towards a time when traditional open surgery is a thing of the past. Just 8 centimetres long, the devices are designed to be slipped inside a patient’s abdomen through a tiny incision. Once inside the body, the robots can be controlled by surgeons either on-site or hundreds of kilometres away. The miniature medics are equipped with lights and a camera to relay video images back to their operator, and an array of different tools that could help surgeons stop internal bleeding by clamping or cauterizing wounds.

The devices were invented by a team of engineers and doctors from the University of Nebraska Medical Centre, Omaha, and the University of Nebraska in Lincoln. “This is just the start of things to come,” says team member and surgeon Dmitry Oleynikov. “At some point the surgeon’s hands won’t need to be in the body at all.” Robot-assisted surgery gives doctors greater precision than using their own hands, and it is easier to reach some parts inside the body using flexible mechanical joints.

In 2000, surgeons at the Washington University School of Medicine in St. Louis conducted the first pilot trial of robot-assisted heart surgery, and a wide range of procedures now use mechanized instruments. A year later, doctors in New York used a remote-controlled robot to remove a gall bladder from a woman in Strasbourg, France. Robotic instruments that can be manipulated through a ‘keyhole’ cut in the patient avoid the trauma caused by larger incisions. But Oleynikov points out that small incisions can constrain the reach of the implements and obscure the surgeon’s view of the operating site. Self-contained robots that go right inside are much more versatile, he argues. “This has been on the cards for a while,” says Michael Lamperth, who works on medical robotics at Imperial College London. “There’s a lot going on with robots that work from inside the body.”

The devices might even help out on the battlefield, the Nebraska team argues. The robots could be inserted directly into wounds, giving surgeons away from the front line the chance to assess damage and determine how to keep a soldier alive. The team also plans to test a biopsy robot, which could bring back samples of tissue from deep within the body. And in spring 2006, NASA astronauts will take the robots with them on a trip to the Aquarius underwater laboratory off the coast of Florida, to practice a simulated appendectomy guided by surgeons back on shore.

Lamperth says that miniature robots are best suited to working in the digestive tract, which they can enter through the anus without the need for an incision. “I wouldn’t expect them to do heart surgery with these,” he says. But Oleynikov points out that their devices should be equally at home within the abdominal or chest cavity. The devices would have to be approved by the US Food and Drug Administration before seeing widespread use, but the team is hopeful that clinical trials could begin within a year. ‘But Lamperth cautions that clinical trials are only the first of many regulatory hurdles the robots will have to clear before they see widespread use.

If trials do prove successful, the robots could become even smaller. “If we were to make 1,000 robots, we would be able to afford customized electrical components that would reduce the size of the robot by half,” predicts biomedical engineer Mark Rentschler, part of the Nebraska team.

Nature
November 22, 2005

Original web page at Nature

A new device for removing liver tumours with virtually no blood loss has been successfully used for the first time in America. The Habib 4X resection device is named after its inventor Professor Nagy Habib, Professor of Hepato-Biliary Surgery at Imperial College London and chief of service for gastrointestinal surgery at Hammersmith Hospitals NHS Trust in west London. The revolutionary new device uses radiofrequency energy to ‘seal’ tissue around a tumour site, allowing the tumour to be removed while preventing blood loss and other complications. The device has enabled surgeons to operate where previously it would have been too risky. The Habib 4X works by delivering high-energy radio waves through a hand held device consisting of four electrodes into tissue around the tumour. They heat cells causing them to dehydrate and thus form a seal. The tumour is removed with a scalpel, with virtually no blood loss, and without the use of staples, glue, ties, and sutures.

Before use of the device in the UK for the removal of liver tumours, patients often lost up to ten pints of blood during the operation. Now, less than 50ml (an egg-cup full) is lost, and the patient spends less time in hospital intensive care. Over 100 patients have been operated on with the new device since October 2004, and none have died or suffered serious illness after the operation. The average hospital stay has been reduced from two weeks to eight days. When patients were followed up over a period of between two and 20 months, tumours had not returned in any of them. “The liver is the second commonest site of cancer in the body,” comments Professor Habib, “So the potential of the Habib 4X is huge. The first use of the device in America is a significant and exciting milestone.”

Science Daily
September 27, 2005

Original web page at Science Daily

The application of a small number of fetal cells can heal the wounds of young burn victims, researchers in Switzerland report. The new procedure can produce a speedier and more complete recovery than traditional skin grafts, they say. The source of the healing cells may prove controversial in countries such as the United States, however, as they came from an aborted fetus. Doctors typically treat deep second- and third-degree burns with skin grafting. In this two-step surgical procedure a patch of skin is removed from one area of the body and transplanted to cover the wound. This can be effective, but often leaves the patient with a scar and may take months to heal.

Patrick Hohlfeld of the University Hospital in Lausanne, Switzerland, and his team decided to explore the potential of fetal skin cells in grafts. Fetuses have long been known to have remarkable regenerative abilities. Hohlfeld says he expected the skin cells to act as a graft. But the cells seemed to confer restorative powers to the burnt skin, allowing the damaged tissue to heal itself. The team doesn’t know exactly how the skin cells had this effect. But Hohlfeld thinks the technique could work for adult burns, as well as other wounds. “We have not tested this healing process in older patients, but there is no reason to think otherwise,” he says.

The team obtained the fetal cells from a woman whose pregnancy was terminated at 14 weeks. They allowed the cells to divide in the laboratory, and then seeded them onto a bed of collagen – an important protein for skin elasticity – and incubated them for two days. This procedure can source several million 100-cm2 patches for transplant from a single fetal biopsy, they say. Eight burn victims, ranging in age from 14 months to 9 years, underwent treatment. Hohlfeld and his colleagues placed tiny swatches of cells onto the burn wounds and covered the area with gauze. The treated wounds took an average of 15 days to heal, the team reports in The Lancet. “The nurses couldn’t believe the speed at which these burns healed,” Hohlfeld says. Other forms of treating similar burns frequently take up to six times as long. The remarkable flexibility of the skin mended with the fetal cells meant that the patients recovered full movement of their hands and fingers, the authors add. The result not only gave the patients nearly perfect skin, but also spared them the trauma of having a graft taken from elsewhere on their body, Hohlfeld adds.

Nature
September 13, 2005

Original web page at Nature

Wound healing is slow when an animal is stressed, but extra oxygen almost completely reverses the effect, according to researchers at the University of Illinois at Chicago. In a study of laboratory mice, Phillip Marucha, professor of periodontics at the UIC College of Dentistry, and his colleagues found that psychological stress, brought on by confinement, delayed the closing of wounds by more than 45 percent. “The cells that help remake tissue didn’t differentiate the way they would have in normal animals. They didn’t line up the way they were supposed to. And they didn’t develop the tiny contractile fibers that help pull together the edges of the wound,” Marucha said. “Expression of the gene that codes the protein for those fibers was impaired.” However, when the animals received hyperbaric oxygen (oxygen at a greater pressure than atmospheric oxygen), the delay in healing was almost eliminated.

Marucha said stress launches a sequence of events that constrict blood vessels and deprive the tissues of oxygen. “Without sufficient oxygen, tissues can’t heal,” he said. “Oxygen activates the inflammatory cells of the immune system that help healing. Also, oxygen derivatives like bleach and peroxide are part of the arsenal of noxious products that these cells use to kill the bacteria in wounds.”

The researchers hypothesized that the hyperbaric oxygen therapy reversed the delay in healing not because it relieved stress, but because it helped directly in wound healing. To test that hypothesis, they measured levels of expression of the gene for an enzyme called inducible nitric oxide synthase, which makes nitric oxide. Nitric oxide is critically involved in wound healing, by increasing blood flow and the delivery of oxygen, and by attacking bacteria. If oxygen levels fall, the gene’s activity increases.

The researchers found that when animals were stressed, expression of the gene increased, presumably to help make more nitric oxide. But when the animals received hyperbaric oxygen, gene expression returned to normal levels, suggesting that the nitric oxide levels necessary for healing had been restored by the increased tissue oxygen levels.

Source: University of Illinois at Chicago

Bio.com
August 16, 2005

Original web page at Bio.com