Tag: Surgery (Orthopeadics)

Though robots were once the stuff of Star Wars and The Jetsons, commercially available systems have made robotic surgeries common in hospitals. Located just feet away from the surgeon, the systems are minimally invasive and offer surgeons better dexterity. Department of Defense-funded researchers want to take that capability to the next level so surgeries can commence on battlefields with the surgeon’s work being done by a robot that’s miles away and connected by communication links.

“There is a large community that is envisioning a robot that is deployable in an armored vehicle, much closer to combat, where an expert surgeon can remotely work on the patient very quickly after an injury is sustained,” said Dr. Blake Hannaford, a professor of electrical engineering and adjunct professor in bioengineering and mechanical engineering at the University of Washington. “The kind of focus, as I understand it, is stopping arterial bleeding that’s not amenable to a tourniquet … and stabilizing that so that a Soldier can be transported for regular care.”

Hannaford and his team have created a surgical robot that works on a patient’s abdomen. It has two arms, and a motorized carriage on the operating table lets the arms move anywhere on the table. “It’s very position-able to any part of the body,” he said, adding that this may possibly allow the robot be used on arms and legs. Hannaford’s research endeavors were funded, in part, by a grant from the DoD’s Peer Reviewed Medical Research Program. Congress created the program in 1999 to promote research in health issues the military faces. Since its inception through 2005, the program has spent almost $300 million to fund nearly 200 projects in a range of medical topics, including combat casualty care and technology and infectious disease research. Along with Hannaford, Drs. Jacob Rosen, Mika Sinanan and Richard Satava are also co-investigators on the grant. “We’re established in this area because of this grant,” he said. “There’s a good chance we wouldn’t be in this field if not for this grant.”

Hannaford didn’t set out to create a robot. His initial grant, from the Defense Advanced Research Projects Agency, was to measure surgeons’ movements and develop a way to evaluate their skills statistically with software. “Surgical training is modeled like a medieval apprenticeship: You go to med school and then you have a residency where you hang out with a surgeon and watch, and they let you help out a little bit and you try more and more parts of the operation,” he said. “It isn’t formalized. There aren’t official milestones for each year.” After completing that research, Hannaford took his data on surgeon movement and crafted his robot. Renowned telesurgeon Dr. Tim Broderick put the robot through its paces June 3-11 in Simi Valley, California via a communications link that was bounced off an unmanned aerial vehicle, Broderick operated Hannaford’s robot first from the valley and then from Seattle.

The desert experiment was a success, said Dr. Gerry Moses of the Telemedicine and Advanced Technology Research Center, which also funds part of Hannaford’s research. “It encountered some challenges with the communications link, but there were no considerable technical challenges. In fact, this gave us a roadmap of what we need to work on next,” he said. Not having surgical expertise in remote areas is not just a military issue, Hannaford said. The University of Washington in Seattle is the only medical school in five states and has patients who hail from Alaska, Montana, Idaho and Wyoming. “There are patients in Alaska who are 1,700 miles from Seattle. If their little clinic can’t handle the problem, they come all the way to Seattle. Some patients might be resistant to the idea (of robotic telesurgery) at first, but surgeons have found many patients receptive to the technology, and if they can be taken care of in their own community, there’s a benefit,” he said.

For example, a surgeon in Canada, Dr. Mehran Anvari, has conducted more than two dozen robotic telesurgeries via the Canadian telephone system on patients who were 250 miles away. Robotic telesurgery may also bring specialized surgical skills to military field hospitals where they may be in short supply. Neither Hannaford nor Moses say that robotic telesurgery will be on the battlefield next month or next year but they do believe that with hard work it will be there in the not-too-distant future. “We’re not talking about something that’s going to be immediately available, but if we don’t do this research now, we will not have the option of having surgical intervention remotely or robotically (on the battlefield),” Moses said.

Science Daily
September 12, 2006

Original web page at Science Daily

Mayo Clinic ear, nose and throat surgeons have developed a promising new process for mandible (lower jaw) reconstruction following removal of oral cancer. Details will be presented June 28 at the International Federation of Head and Neck Oncologic Societies meeting in Prague, Czech Republic. “We think this new process can be a huge advantage for patients and a good tool for reconstructive surgeons,” says Daniel Price, M.D., Mayo Clinic ear, nose and throat surgery resident and lead study investigator. “We’re excited about it. It will not completely replace the current mandible reconstruction method — transfer of bone — but down the road, I think that this method of reconstruction will be done regularly in patients with cancer involving the mandible.”

Patients who might be candidates for the new reconstructive and treatment procedure have oral cancer involving part of the mandible. To completely remove the tumor surgically, surgeons have to remove part of the mandible. Without reconstructive surgery, patients would have difficulty eating and speaking, and would develop a significant facial deformity, says Eric Moore, M.D., Mayo Clinic ear, nose and throat surgeon and senior study investigator. The new method, which the investigators tested in rabbits, used distraction osteogenesis after tumor removal surgery to restore the missing portion of a patient’s jaw. With distraction osteogenesis, the surgeon made a cut at one of the remaining ends of the patient’s jawbone. As the break healed, the first phase of growth, soft tissue, appeared. The surgeon then stretched the pliable soft tissue under the tension of a device to fill in the gap in the patient’s jaw. Within 24 hours of completing the stretching process, physicians started administering radiation therapy to the mandible to decrease the likelihood of cancer recurrence. As the soft tissue healed, it hardened into bone. The investigators found that the radiation therapy, which they had suspected could interrupt the bone consolidation prior to the study, had no ill effects on the bone’s healing.

“Patients with large oral tumors should have radiation therapy after surgery to decrease the chances of cancer recurrence,” says Dr. Price. “Radiation needs to be completed 13 to 14 weeks after the patient’s cancer diagnosis to achieve maximum effect. As these patients require mandible reconstruction after tumor removal, we wanted to find a way to get both the radiation and the reconstruction done quickly and concurrently.” Dr. Price says that it is also preferable to start the reconstruction when the tumor is removed, as demonstrated in this method, rather than wait until radiation therapy is completed, because immediate reconstruction minimizes scar tissue and is better tolerated by the patient. The standard procedure for jaw reconstruction following removal of an oral cancer is transfer of bone from the patient’s fibula in the leg, along with surrounding muscle, skin and the supplying vessels. Although the aesthetic and functional result for the mandible can be good, this procedure has drawbacks, including:

The surgery takes all day to complete and is expensive. The patient has a second surgical site to heal (leg and mandible) and is less mobile post-surgery. In male patients, the transfer of fibula and surrounding skin can lead to the appearance of leg hair inside the patient’s mouth. The surgery is not feasible for patients who do not have healthy vessels in their legs. The aesthetic result in the leg post-surgery is less than ideal. The surgery can inadvertently damage the leg’s nerves, leaving the patient with some leg weakness. The fibula bone can die following transfer. “If we could avoid the whole process of going to another part of the body in order to reconstruct a patient’s jaw, it would be best,” says Dr. Moore.

Drs. Price and Moore had been performing similar distraction osteogenesis in children born with small jawbones and wondered about the feasibility of using the procedure for adult oral cancer patients. Thus, they embarked on this research project to test it in animals and have tried this method on human oral cancer patients who were not appropriate candidates for the fibula transfer surgery. They have also utilized the method in patients who have benign tumors or who have suffered a trauma. The patients who have had distraction osteogenesis performed by Drs. Price and Moore compared the level of discomfort to having orthodontic braces. The devices used for the stretching procedure are submerged and not visible. The next step in this research, according to Dr. Price, is to study the distraction osteogenesis plus radiation therapy method in larger animals, comparing them to animals who are given distraction osteogenesis without radiation therapy.

Mayo Clinic
August 1, 2006

Original web page at Mayo Clinic

Orthopaedic implants help millions of Americans stay active. But these medical devices are prone to infection, forcing patients back to surgery for repair or replacement. Now, for the first time, a team of engineers has shown that zinc or titanium oxide nanosurfaces can reduce the presence of bacteria, a technique that can be applied to implants to reduce the number of these costly and debilitating infections. Thomas Webster, an associate professor of engineering at Brown, led the research. Results are published in the Journal of Biomedical Materials Research. “We’ve found a method of coating implants that discourages bacteria growth,” Webster said, “and it does so significantly. The hope is that this technique will lead to safer, longer-lasting implants.”

According to the American Academy of Orthopaedic Surgeons, 766,100 Americans underwent surgery for hip, knee and shoulder replacements in 2002. During typical procedures, surgeons remove an arthritic or damaged joint and replace it with an artificial one. In about 1 to 2 percent of cases, the implant gets infected. The most common culprit: Staphylococcus epidermidis. Found on skin or in mucous membrane, S. epidermidis can enter a surgical wound and adhere to an implant. The bacteria multiply, causing a slimy layer, or biofilm, to form around the implant. The slime is tough stuff, acting as a physical and chemical barrier that resists antibiotics. The result is additional surgery to clean the implant or replace it outright.

Webster, along with former Purdue University colleagues Gabriel Colon and Brian Ward, knew that abrading or coating implants to produce microscopic bumps, which create a sand-papery surface, aid in bone growth. This helps anchor the implant in the body and extends its life. Some artificial joints now sport these microstructured surfaces. But the team wondered if smaller peaks and craters – ones that measure on the nanometer scale – would work even better. And how would bacteria react? So they experimented.

The engineers chose zinc and titanium oxides as their materials. Zinc oxide is a well-known antimicrobial agent. Titanium oxide, strong and light, is a commonly used in implants. Engineers took nanoparticles of these ceramics and pressed them into dime-sized discs. They took microparticles of these same materials and made more discs. Discs with nanostructured surfaces had bumps that measured only .023 microns in diameter. Discs with microstructured surfaces had bumps that measured about 5 microns in diameter. Under a microscope, the surface differences are extreme; the nanostructured discs look like saw-toothed mountains, the microstructured discs look like smooth plateaus. The engineers put S. epidermidis on the discs and waited an hour. Then they counted the bacteria. The results were dramatic. Microstructured zinc oxide discs were host to 1,000 times more bacteria than the nanostructured zinc oxide discs. Similar, but less striking, results were duplicated on titanium oxide discs. The engineers conducted similar experiments with bone-forming cells and found that twice as many of these cells grew and formed bone on nanostructured discs. Other indicators of healthy bone growth, such as collagen synthesis, were also stronger with nanostructured discs.

“Surface area seems to be key,” Webster said. “With the nanostructured surfaces we created, surface area increased by 25 to 35 percent. We think that this additional area, along with the unique surface energetics of these nanomaterials, gave bone-forming cells more places to adhere. But with bacteria, increased surface area may work the other way, exposing the bugs to more of the germ-fighting properties of the zinc oxide.”

Science Daily
July 18, 2006

Original web page at Science Daily

A new Mayo Clinic study reviewed CT scans of pancreatic cancer patients done before their cancer diagnosis and found that the cancer rapidly progresses from early to advanced stage in the six months prior to traditional clinical diagnosis. The study also found that in one-half of the diabetic patients, their new-onset diabetes predated clinical diagnosis of cancer by more than six months, giving researchers one more clue for earlier detection of pancreatic cancer. “Past studies have shown an association between recent diagnoses of diabetes and pancreatic cancer,” says Suresh Chari, M.D., a Mayo Clinic gastroenterologist and lead author of this study. “Our goal with this study was to establish a timeline for the progression of pancreatic cancer, especially in relation to the development of new-onset diabetes.”

Pancreatic cancer, the fourth leading cause of cancer death in the United States, claims nearly 32,000 lives each year. Patients with this type of cancer seldom exhibit disease-specific symptoms until the cancer is at an advanced stage and surgery is no longer an option, therefore, fewer than 5 percent of pancreatic cancer patients survive five years after diagnosis. This study population consisted of 23 patients who underwent at least one CT scan for unrelated reasons before the diagnosis of pancreatic cancer. Dr. Chari’s team found that while 70 percent of patients had advanced cancer at diagnosis, all scans done six months or more prior to diagnosis showed no evidence of the cancer.

Fourteen patients in the study had data on diabetes and its date of onset could be established. On average, the cancer was diagnosed five months after the diabetes first developed, and in 50 percent of patients, the diabetes occurred six months or more before the diagnosis of cancer. All scans done prior to the onset of diabetes were normal; however, by the time the cancer was diagnosed, 80 percent of the patients were already in advanced stages of pancreatic cancer and could not be treated with surgery.

“This research is encouraging because it shows that when patients with pancreatic cancer first exhibit high blood sugar, there’s still time to diagnose the cancer early enough to be treated by surgery,” says Dr. Chari. However, type 2 diabetes is far more common than pancreatic cancer-induced diabetes. According to Dr. Chari, only one in 100 to 200 patients with new-onset diabetes will be diagnosed with pancreatic cancer. “We are, therefore, not recommending that all new-onset diabetics undergo screening,” he says. The question Dr. Chari’s team now faces is identifying another clue to determine who among the group of patients with new-onset diabetes have a high likelihood of developing pancreatic cancer.

“Because of the connection with diabetes, we know there’s a clue in the blood of these patients,” says Dr. Chari. “Our next step is to determine whether the pancreatic cancer is actually producing something that is causing a unique form of diabetes. If that’s the case, we want to identify that ‘something’ to differentiate between pancreatic cancer-induced diabetes and regular type 2 diabetes.” The eventual goal of this research is to identify another layer of screening (in addition to tests for high blood sugar) to identify individuals who are more likely to have pancreatic cancer — allowing for earlier detection and increased opportunity for surgical treatment.

Mayo Clinic
June 20, 2006

Original web page at Mayo Clinic

Two surgical procedures, one invasive and the other much less so, for premature infants with intestinal perforation due to necrotizing enterocolitis (NEC) produce virtually identical results, according to a Yale School of Medicine study published today in the New England Journal of Medicine. A significant aspect of the study is that it is the first multi-center randomized controlled trial to be completed comparing two operations in children, said the lead author, Larry Moss, M.D., chief of pediatric surgery in the Department of Surgery.

“Surgery is one of the most dramatic and potentially life-altering events in a patient’s medical life, yet a remarkable amount of surgical practice is based upon historical tradition rather than scientific evidence,” Moss said. “The vast majority of research on surgical conditions involves a single group of surgeons reporting upon their personal experience at one institution.” “This report argues against conventional wisdom that randomized studies cannot be effectively utilized to compare treatments for acutely life-threatening conditions,” he said. “It proves that despite the biases against surgical trials, they can be completed with appropriate commitment by surgeons and their institutions.”

NEC is a severe inflammatory disease of the intestine afflicting 5,000 to 10,000 premature infants in the United States each year. In its most severe form NEC results in perforation of part of the intestine which requires emergency surgery that can be life-saving. For more than 25 years surgeons have used two radically different operations for these babies. The first and more aggressive, laparotomy and bowel resection, involves a large abdominal incision with removal of all affected intestine and creation of a stoma, which means bringing the end of the intestine through the abdomen to drain into a bag. The alternative option, peritoneal drainage, involves making a ¼ inch incision in the lower abdomen and placing a small drain allowing egress of stool and pus from the abdomen without removing any intestine.

The trial led by Moss included 117 premature infants at 15 leading pediatric academic medical centers from the United States and Canada. When a baby developed perforated NEC at a study site, parents were counseled by the operating surgeons and offered enrollment into the trial. If they agreed, the operation their child received was assigned randomly. “The study found that patient survival and other major outcomes for the two drastically different operations were virtually identical,” he said. “After 30 years of debate over which procedure is best, the first true scientific experiment addressing this question suggests that the method of the surgery may not be the important aspect of treatment.”

As a next step, Moss, working with six academic medical centers, is directing collection of clinical and biological information for a database to identify which babies with NEC are at greatest risk of perforation. The team is collaborating with other researchers who are developing promising new therapies that can be tested in this targeted group of patients. “Since the study compared the most aggressive surgical treatment with the least invasive and found no difference, it appears unlikely that ongoing focus on the details of the operation is likely to improve survival in these patients,” he said.

Moss also has developed and tested a set of clinical research reporting guidelines for surgery that revealed there was a lack of evidence for many surgical procedures in children. The tool was then validated on a large sample of several hundred studies. As a result of this work, the Journal of Pediatric Surgery has adopted the guidelines and is using them for all clinical research published in the journal.

Science Daily
June 6, 2006

Original web page at Science Daily

In one of the largest epilepsy surgery studies ever conducted, Mayo Clinic researchers have found that 81 percent of patients with intractable epilepsy become totally or nearly seizure-free six months following epilepsy surgery. Ten years later, 72 percent remained totally or nearly seizure-free. Findings will be published in the April issue of Journal of Neurosurgery. “I think this is very exciting because the surgery not only can stop the seizures following the operation, but it can stop them for the long term,” says Gregory Cascino, M.D., Mayo Clinic neurologist and study investigator. Aaron Cohen, M.D., lead study investigator, agrees. “This shows us seizure surgery is durable — it remains effective and safe over time.” Dr. Cohen is a former Mayo Clinic neurosurgical resident who is now a neurosurgical fellow at University of Arkansas for Medical Sciences.

Epilepsy affects 3 million Americans. Thirty to 40 percent have intractable epilepsy: medications alone do not control the seizures, and the seizures have a disabling effect on quality of life. “All other forms of treatment, specifically maximum anticonvulsant treatment, have failed for these patients,” says Fredric Meyer, M.D., chair of Mayo Clinic Department of Neurologic Surgery and study investigator. “Often these patients are on two to three anticonvulsants and are still suffering from intractable epilepsy prior to surgery.” To conduct this study, the researchers analyzed the cases of 399 consecutive patients who underwent epilepsy surgery to remove the focal region of their disease in the brain at Mayo Clinic in Rochester, Minn., between 1988 and 1996. There were 214 females and 185 males, and the average age at surgery was 30.

Prior to surgery, quality of life is poor for these patients, the Mayo Clinic researchers explain. “These patients typically can’t drive or use dangerous machinery, have difficulties with work or can’t work at all, or can’t complete their education,” says Dr. Cascino. “They usually would have several seizures per month and may be prone to having spells with loss of consciousness. They can injure themselves from seizures, drown or have sudden unexpected death due to epilepsy.” Quality of life typically improves dramatically after surgery, says Dr. Meyer. “If these patients have improved seizure control after surgery, which most of them do, then there is an incredible paradigm shift toward a better quality of life,” he says. “These patients break out from the stigmata of epilepsy and find employment, often drive, and lead a productive life.”

Risk with epilepsy surgery is relatively low: 4 percent of patients studied had medical problems due to anesthesia or other neurological complications during surgery. Risk varies by seizure type, where the seizure focal region is located, and other factors, according to Dr. Meyer. Though epilepsy surgery is not risk free, Dr. Cascino notes that patients with intractable epilepsy are continually at risk already before surgery due to their disease. “This is a big operation for a big medical problem,” he says. “These patients are medically, physically and socially affected by their disease.” Dr. Cascino says that it is cost-effective for society when surgery can stop a patient’s seizures, due to the significant number of epilepsy patients who are unemployed or underemployed because of their seizures.

An appropriate candidate for epilepsy surgery is in good health, with the exception of epilepsy; is not responding to seizure medications; the region of the brain affected by the disease can be pinpointed; and the affected region of the brain can be safely extracted without damaging the surrounding area. Though 30 percent to 40 percent of epileptics might be candidates, the surgery is underutilized, according to Dr. Cascino. He says the surgery is available at medical centers designated level IV comprehensive epilepsy centers by the National Association of Epilepsy Centers (http://www.naecepilepsy.org).
For those who are not surgical candidates, other treatment options are available, says Dr. Cascino. “Patients suffering from epilepsy should seek an evaluation at an epilepsy center and not give up hope,” says Dr. Meyer. “There may be very excellent options to help them.”

Mayo Clinic
May 9, 2006

Original web page at Mayo Clinic

A bacterium that lives in rivers, streams and human aqueducts uses nature’s strongest glue to stay in one place, according to new research by Indiana University Bloomington and Brown University scientists reported in the Proceedings of the National Academy of Sciences (April 11). The scientists found they had to apply a force of about 1 micronewton to remove a single Caulobacter crescentus from a glass pipette. Because C. crescentus is so small, the pulling force of 1 micronewton generates a huge stress of 70 newtons per square millimeter. That stress, which the bacterial adhesions could sometimes withstand, is equivalent to five tons per square inch — three or four cars balanced atop a quarter. By contrast, commercial “super” glue breaks when a shear force of 18 to 28 newtons per square millimeter is applied. Hypothetically, C. crescentus’s glue could be mass produced and used to coat surfaces for medical and engineering purposes.

“There are obvious applications since this adhesive works on wet surfaces,” said IU Bloomington bacteriologist Yves Brun, who co-led the study with Brown University physicist Jay Tang. “One possibility would be as a biodegradable surgical adhesive.” C. crescentus affixes itself to rocks and the insides of water pipes via a long, slender stalk.
At the end of the stalk is a holdfast dotted with polysaccharides (chains of sugar molecules). The scientists show in the PNAS paper that these sugars are the source of C. crescentus’s tenacity. It is presumed these sugars are attached to holdfast proteins, but this has not yet been confirmed. One thing is certain — the polysaccharides are sticky. “The challenge will be to produce large quantities of this glue without it sticking to everything that is used to produce it,” Brun said. “Using special mutants, we can isolate the glue on glass surfaces. We tried washing the glue off. It didn’t work.”

The scientists allowed C. crescentus to attach itself to the side of a thin, flexible glass pipette. They used a micromanipulator to trap the cell portion of the bacterium and pull it directly away from the pipette, measuring the force of strain. In 14 trials, the scientists found they had to apply a force of 0.11 to 2.26 micronewtons per cell before the bacterium detached. C. crescentus has evolved an ability to live in extremely nutrient-poor conditions, which explains its existence as a common fixture in tap water. Because it exists in tap water at low concentrations and produces no human toxins, C. crescentus poses no threat to human health.

Science Daily Health & Medicine
April 25, 2006

Original web page at Science Daily Health & Medicine

Research to be published in the April 18 issue of the Journal of the American College of Cardiology provides the first explanation of an active rather than passive process that leads to heart valve degeneration, furthering a Northwestern researcher’s effort to lead a paradigm shift in the medical community’s beliefs about the cause of valve disease. Heart valve disease is caused not by a ‘wear and tear’ phenomenon, but by an inflammatory process likely triggered by high cholesterol that stimulates certain cells to reprogram into bone cells in the aortic valve and cartilage cells in the mitral valve, says principal investigator Nalini Rajamannan, MD, newly appointed director of the Center for Heart Valve Disease in the Bluhm Cardiovascular Institute of Northwestern Memorial Hospital and assistant professor of medicine, Northwestern University Feinberg School of Medicine, who examined diseased mitral and aortic valves removed during surgery for the study.

“Common wisdom in the medical community has always been that thickening of the mitral valves was part of the aging process as deposits of calcium, a mineral found in the blood, built up on the valves. Therefore, research has never focused on preventing the problem,” says Dr. Rajamannan. “Currently the only option is to surgically repair or replace the damaged valves. Our findings open the door to the idea that medical therapies such as statins may be able to play a role in preventing or slowing the process and curtailing the need for surgery.” Valvular heart disease is on the rise with the aging of the United States population, and is second only to coronary artery disease as a cause for open heart surgery. Heart valve disease leads to 100,000 surgeries in the U.S. each year to repair or replace damaged valves. Mitral valve disease is a leading cause of atrial fibrillation, which is a major culprit in strokes and heart failure. Aortic valve disease can lead to heart failure, arrhythmia, infections in the heart, and sudden death may occur in 15 to 20 percent of people who have symptoms.

Dr. Rajamannan has focused her research for the past seven years on advancing the knowledge of mechanisms of aortic and mitral valve disease using animal models and human studies. “I wanted to know why diseased valves were hardened with a glassy whitish appearance — totally different than healthy tissue, which indicated to me that the actual structure of the valves had changed,” she says.
Dr. Rajamannan has been awarded over $750,000 in grants from the NIH and the American Heart Association to pursue this research. Dr. Rajamannan’s laboratory was the first to treat animals with calcifications in heart valves with medications called statins, the same drugs that are currently used to treat high cholesterol. In an early pioneering study, animals treated with statins had significantly less heart valve disease than the control animals that were not treated. The results from the animal studies and now with the human valves demonstrate that valvular heart disease has an active biology which can be treated with medications similar to that of coronary artery disease.

“As with the majority of people in the field who hear about this research, I was surprised when Dr. Rajamannan’s unique observations indicated that the process of valve degeneration is instead an active process, linked to inflammation and cellular growth,” says Robert Bonow, MD, co-director of the Bluhm Cardiovascular Institute. “The exciting news is that this line of research suggests that there may be medical treatments in the future that could either treat this disease process.”

Science Daily Health & Medicine
April 25, 2006

Original web page at Science Daily Health & Medicine

Neurosurgeons at Thomas Jefferson University Hospital in Philadelphia are the first in the region and among the first in the nation to successfully use a new stent specifically designed to open potentially life-threatening clogged arteries in the brain, preventing a stroke. The device, called the Wingspan™ Stent System, is used for individuals with intracranial atherosclerotic disease, which results from too much plaque in brain arteries. The condition accounts for about eight to 10 percent of strokes due to ischemia, or some 60,000 strokes in Americans each year.

Traditional medical management for such blockages using blood thinners such as Coumadin and aspirin is frequently ineffective. Doctors have tried using heart stents – the mesh metal tubes placed in a coronary artery to keep it open after an interventional procedure – but they are stiff and not meant for the more fragile blood vessels in the brain. The Wingspan Stent is self-expanding and is placed using minimally invasive techniques. It is threaded through an artery in the leg. “It’s the first self-expanding stent for intracranial use designed specifically for atherosclerotic disease in the brain,” says Robert Rosenwasser, M.D., chair of neurosurgery at Thomas Jefferson University Hospital. Dr. Rosenwasser, who is a professor at Jefferson Medical College of Thomas Jefferson University continued, “With stent technology and the proper tools, we should be able to lower the risks of treating the disease because these devices are designed specifically for cerebral blood vessels.”

Instead of steel, the most commonly used material for traditional coronary stents, the Wingspan stent is composed of nitinol, an alloy of nickel and titanium. This design puts less pressure on the blood vessel when it expands. Previously, patients had few options. “Up until recently all we could do was offer anticoagulants such as Coumadin, Plavix and aspirin to avoid a stroke,” explained Erol Veznedaroglu, M.D., assistant professor of neurosurgery at Jefferson Medical College of Thomas Jefferson University. “These patients either responded to medical therapy or were given devices that were less than ideal,” Dr. Rosenwasser says.

But blood-thinning drugs fail to open blockages in brain arteries in 30 percent of cases, putting patients at high risk for stroke. And even many of those who initially respond to such medications often go on to have another stroke in the next year. Stroke is the third leading cause of death and disability in the United States, according to Dr. Rosenwasser. He notes that some 80 percent of strokes are due to brain injuries caused by a lack of oxygen, such as those from the buildup of plaque in blood vessels. Only 20 percent are due to hemorrhage. Dr. Rosenwasser, who is also director of the Division of Cerebrovascular Neurosurgery and Neuroradiology at Jefferson Medical College and Thomas Jefferson University Hospital, pointed out that using other means, such as balloon angioplasty, to push aside plaque, has high complication rates, about 18 to 20 percent.

“What’s so exciting here is that we’ll begin seeing a host of patients who were never able to be treated before,” says Dr. Veznedaroglu. “This is really a revolution for the treatment of this disease and we expect the Wingspan stent to be used frequently.” “The device will allow us to treat more patients up front before they exhaust medical therapy,” says Dr. Rosenwasser. Doctors don’t know yet if the stent can be used preventatively. Dr. Veznedaroglu thinks it can. “With a safe stent, I think you’ll see eventually that it is better than the best medical management,” he says. “But it’s just too soon to know. We’ll need long-term studies to find out.”

The Wingspan stent is not a panacea. Atherosclerotic disease and plaque buildup (as coronary artery disease) can return, he notes, despite a stent. Stents do not stop what causes the clogging to occur, so they will not prevent the disease. Scar tissue is also a problem, just as it is with coronary disease. Early experience, however, indicates that cranial vessels may not develop as much plaque as do arteries around the heart. The procedure is performed similarly to coronary artery stent placement or placing a coil for an aneurysm. The surgeon snakes a catheter through the femoral artery and into the blood vessel in question. With the aid of X-rays, the surgeon navigates the stent device into the cerebral circulation to the precise location of the narrowing and blockage.

The stent is self-expanding, meaning a balloon is not required to open it (as it is in coronary artery stents). It essentially opens automatically when it comes out of the catheter. The catheter is inserted through the blockage, and a balloon is inflated with low pressure to slowly open the clog. The balloon and catheter are removed, and the stent is released from a second catheter. The procedure can last from 30 minutes to two hours, depending on the complexity of the case. Patients may leave the hospital as soon as 48 hours later. Recovery time will be dictated by the patient’s neurological condition. Ideally, a patient could return to work in a week. Dr. Veznedaroglu and Jefferson are participating in a prospective trial, led by researchers at the State University of New York, Buffalo, which looks at the use of the Wingspan stent in patients who have had an acute stroke and occlusion in a brain artery.

Science Daily
April 11, 2006

Original web page at Science Daily

Endoscopic surgery brings many advantages for patients but is very difficult for the surgeon. Working at the Academic Medical Centre in Amsterdam, Joris Jaspers has developed two instruments which make this approach easier and also cheaper than with existing surgical robotics. Jaspers is awarded his doctorate on Wednesday 22 March at Delft University of Technology.

Endoscopic operations (or keyhole surgery) are much less stressful for the patient and give a better cosmetic result than ‘open’ surgery. But on the other hand, it is very difficult for the surgeon to carry out keyhole surgery. This is due to the disruption of hand-eye coordination, as the surgeon has to operate via a 2D image on a monitor. Moreover, the video camera has to be operated by an assistant and the work must be done using long and rigid instruments that provide little freedom of movement. The existing robot systems that have been developed to solve the aforementioned problems are complex, expensive and do not provide the required (force) feedback to the surgeon.

The aim of Joris Jaspers’ research project was to develop simple mechanical alternatives to these complex robotic systems, and also to test them. Jaspers is a doctoral student at the department of Mechanical Engineering of Delft University of Technology, but the greater part of his work is conducted at the Academic Medical Centre (AMC) in Amsterdam, where in recent years he has developed and evaluated two instruments in collaboration with surgeons.The first instrument is a camera and instrument holder. Using this mechanical arm the surgeon can operate the camera himself (with one hand), thus allowing him to conduct the operation by himself without a (camera) assistant. A test showed that this enabled ‘solo surgery’ and that it even brought advantages in comparison to surgery using an assistant.

The second instrument developed by Jaspers is a mechanical manipulator for operating the various instruments used in keyhole surgery. Two mechanical arms, provided with artificial ‘wrist joints’ for extra freedom of movement, transmit the surgeon’s hand movements exactly onto the instruments. This is achieved using rods, cables and parallelogram constructions.This mechanical manipulator thus fulfils a similar function to the surgical robot systems, but in a simpler and cheaper manner. In a test carried out with experienced medical students, the manipulator was compared to the existing (rigid) instruments. This study showed that far fewer actions were needed when using the manipulator and that fewer mistakes were made than with the existing instruments.Jaspers will now further develop this mechanical manipulator, supported by funding from the Ministry of Economic Affairs and in collaboration with engineering firms. Work on his camera and instrument holder is now complete and it will be commercially available in the near future.

Science Daily
April 11, 2006

Original web page at Science Daily

Many patients with diseased thyroids have two safe, effective treatment options that can dramatically reduce the size of their neck incisions and speed recovery, researchers say. Options include minimally invasive thyroidectomy, in which surgeons work through an incision about half the size of the norm, and an endoscopic approach, in which video monitoring and a thin, ultrasonic scalpel reduce incision size another half. “Both work well; both have a place in a usual practice,” says Dr. David J. Terris, chair of the Medical College of Georgia Department of Otolaryngology – Head and Neck Surgery and lead author on research looking at the safety and efficacy of the newer approaches published in the March issue of Laryngoscope.

The online edition also features accompanying surgery video for the first time. Dr. Terris hopes the video of him performing the endoscopic approach will be a good first step for physicians interested in adopting these techniques. Practice on cadavers as well as observing the surgery first-hand are two important additional steps, he says. The study looks at 31 patients who underwent minimally invasive removal of the thyroid gland, which helps regulate metabolic function, and 14 patients in whom pairing the endoscope with the harmonic scalpel, which coagulates as it cuts, enabled the smallest incisions yet for this approach.

Dr. Terris began using a minimally invasive approach to thyroid surgery about two years ago. Today, careful selection of patients based on factors such as the size of the diseased organ and the patient’s anatomy enables him to use this approach in most patients. While most patients with the option prefer a less-invasive approach, the standard approach, which results in a three-to-four-inch incision at the base of the neck, likely always will be needed by some, he says. This includes patients whose gland has grown too large to be removed through a small opening, even with careful manipulation of the gland that typically remains pliable when diseased. In Dr. Terris’ practice, about 30 percent of patients need this approach using a larger incision and moving aside underlying muscle to remove the thyroid.

With one type of minimally invasive technique, surgeons cut through that muscle to gain direct access. During a portion of this surgery, the endoscope enables the surgeon to better see obscure spots such as the very top of the gland and incoming blood vessels. “For the most part we are just looking through a smaller incision,” says Dr. Terris. A newer technique, fine-tuned by Dr. Paolo Miccoli of the University of Pisa, Italy, enables the surgery through an incision less than an inch by pairing the straw-size endoscope with the equally slender harmonic scalpel.

“The harmonic scalpel allows us to safely secure blood vessels in small spaces without needing to tie the vessels,” Dr. Terris says. “You reach up and ligate vessels through endoscope guidance.” Slender instruments also enable surgeons to push aside muscles rather than cut through them. Video monitoring equipment attached to the endoscope magnifies the anatomy about 20 times so surgeons actually can see better than they can through the typical glasses with integrated magnification that enlarge the image about two and one-half times.

In addition to an improved cosmetic result, minimally invasive approaches reduce surgical trauma and recovery time with most patients going home within a few hours of surgery. “We don’t even use stitches on the skin,” Dr. Terris says of the endoscopic approach. “We use a little bit of medical-grade glue.” He notes as the incision gets smaller, surgery time typically gets slightly longer and the surgery team gets larger, including someone to operate the camera with the endoscopic approach.

Science Daily Health & Medicine
March 28, 2006

Original web page at Science Daily Health & Medicine

In the largest published study of its kind, with 1,100 patient cases reviewed, a minimally invasive surgical procedure for lung cancer has been shown to be as effective as open surgery with a low risk of complications and high survival rates when performed by experienced thoracic surgeons. But even though the benefits of the technique have been documented over the past decade — shorter recovery times and hospitalizations, reduced pain, and improved quality of life, for example — it is currently used in only about five percent of the 40,000 lobectomies performed each year in the United States.

An article describing the study appears in the February 2006 issue of The Annals of Thoracic Surgery. It is a follow-up article to one published in the same journal in 1998 that reported on results of video-assisted thoracoscopic surgery (VATS) in 298 patients. Thoracic surgeon Robert McKenna Jr., M.D., surgical director of the Center for Chest Diseases and medical director of Thoracic Surgery and Trauma at Cedars-Sinai, is the principal investigator and senior author. Instead of making an eight- to 10-inch incision, as is done in a typical thoracotomy, VATS requires only four small incisions through which instruments and a thoracoscope are placed. A camera lens at the tip of the scope feeds high-resolution images to a video monitor, providing the surgeon with a detailed, magnified view of the surgical site. A segment, lobe or entire lung can be removed, depending on the patient’s condition and the extent of the cancer.

“At Cedars-Sinai, we now perform 90 percent of our lobectomies by VATS,” said McKenna. “This is the highest percentage of major pulmonary resections done by VATS anywhere in the world. Our data show that it can be safe and our long-term follow-up shows that it results in standard cancer survival. Whether you get access through a big hole or a little hole doesn’t matter. What matters is survival, and survival is the standard survival that you expect for patients after a lobectomy done for cancer.”

Although the size of the incisions may not affect survival, the authors cite a number of recent studies indicating that the minimally invasive approach does result in reduced postoperative pain, better postoperative pulmonary function, and a higher level of patient quality of life. Still, some surgeons have expressed concern about the risk of blood loss with the VATS procedure, as well as the surgeon’s ability to deal with any bleeding that should occur, but studies have actually shown the VATS procedure to result in less blood loss, and according to the Annals article, only seven of the 1,100 cases were converted to an open surgery to control bleeding.

McKenna, whose thoracic surgery group may be the most active in the western United States, suggests that one reason the VATS technique has yet to become the standard of practice is that it can be technically challenging for surgeons who are not accustomed to performing videoscopic procedures and those who do not specialize in chest and lung surgery. A thoracic surgeon since 1982, McKenna is a pioneer in the videoscopic technology and technique. Well known for his research and involvement in National Institutes of Health-funded studies, he has performed and written about VATS procedures since 1992.

“Surgeons who do not have the volume of cases to do pulmonary procedures consistently and regularly will have difficulty developing the skills and routine to do lung surgery this way,” he said. “But we are seeing an increase in the number of institutions and surgeons who are adopting this approach, and thoracic surgeons from around the world come here to learn how to do their lung operations this way.” Of the 1,100 patients included in the study, 595 were women, 505 were men. The average age was 71 years, with 160 patients being 80 years of age or older. The mortality rate was less than one percent, fewer than five percent of patients needed to go to the intensive care unit, and the median length of hospital stay was three days. All operations were performed between February 1992 and December 2004.

“About 20 percent of our patients go home from the hospital on either the first or second day following lobectomy for lung cancer,” McKenna said. “The VATS procedure is not a pain-free surgery. It does hurt; but it does hurt considerably less than standard open procedures. Most patients will be tired and sore for a month or two but VATS tremendously shifts the recovery rate and reduces the pain compared to the standard operation. We have had two patients who played tennis five and six days after having lobectomies this way and two patients who played golf seven days after having lobectomies this way.”

Science Daily
February 28, 2006

Original web page at Science Daily

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