Tag: Soft Tissue Surgery

Mayo Clinic researchers report that freezing kidney tumors through percutaneous cryoablation shows promise for patients who are not good candidates for surgery. Their early findings showing short-term success in more than 90 percent of selected patients are published in this month’s issue of Radiology. The standard treatment for kidney tumors is surgery, providing a high likelihood of a long-term cure. For some patients, surgery is not an option, and Mayo’s urologists and radiologists collaborated to find alternatives for these individuals. If these patients are frail due to age or illness or are not able to have surgery because of other factors, percutaneous cryoablation may be an option. “This procedure appears to be a good option for some patients,” says Thomas Atwell, M.D., Mayo Clinic radiologist and the study’s primary investigator. “It makes their hospital stay and recovery time very short and surgical stress is minimal.” He cautions that this procedure is not ideal for everyone, noting that it is an option for only a relatively small subset of patients.

Percutaneous ablation uses needles to penetrate the skin and deliver directly to the tumor either high-intensity, tissue-destroying heat through radiofrequency ablation, or freezing cold through cryoablation. Mayo Clinic’s radiologists are among the most experienced in the world in performing ablation techniques, and have treated nearly 300 kidney tumors either with radiofrequency ablation or cryoablation. Radiofrequency ablation (RFA) burns away the tumor, while cryoablation freezes it. Mayo Clinic doctors had previous experience with liver tumor cryoablation when they added kidney tumor cryoablation in 2003. Today’s report contains the largest published results for percutaneous cryoablation patients. Mayo researchers report that not only can this technique be an alternative to surgery, but that in some cases, it has benefits over RFA.

Previous experience in percutaneous RFA led the researchers to recognize that it has two important limitations. Tumors larger than 3 centimeters are difficult to treat with RFA, with increased rates of technical failures and tumor recurrence. Also, the area being treated cannot be effectively monitored with computed tomography (CT) or ultrasound. The Mayo study findings show that cryoablation can be used for some larger tumors with simultaneous operation of multiple cryoprobes guided by ultrasound. The ablation margin (the edge of the frozen tissue) can be accurately monitored with CT, to ensure that the total tumor mass is treated. The researchers reviewed the records of the 23 men and 17 women with kidney cancer treated with percutaneous cryoablation at Mayo Clinic between March 12, 2003, and Aug. 4, 2005. They found that this treatment was chosen over RFA for reasons such as larger tumor size, proximity of tumor to ureter or bowel, or a central location on the kidney. Cryoablation was successful in 38 of the 40 patients, with no repeat treatment necessary.

In percutaneous cryoablation, one or more hollow needles are inserted through the skin directly into a tumor. Doctors can observe and guide the insertion by combined use of ultrasound and CT. The needle, or cryoprobe, is filled with argon gas, which results in rapid freezing of the tissue to temperatures of -100° C; and the tissue is then thawed by replacing the argon with helium. The procedure consists of two freezing and thawing cycles, seeking a frozen margin of approximately 5 millimeters beyond the tumor edge to ensure death of the entire tumor. After the cryoprobes are removed, small bandages are placed over the skin puncture sites, and the patient spends one night in the hospital before returning home. Surgeons continue to seek less invasive methods than the traditional radical nephrectomy (removal of cancerous kidney) for the treatment of small tumors, and percutaneous cryoablation is now on the list. With the incidence of kidney cancer steadily increasing over the last 20 years, and the American Cancer Society predicting nearly 52,000 people will be diagnosed this year, with nearly 13,000 dying from it, another option for some patients is good news say the researchers.

Mayo Clinic
April 17, 2007

Original web page at Mayo Clinic

Two common methods for removing kidney stones — surgery and shock wave treatments — are effective and safe, and neither is clearly superior to the other, researchers report in a new systematic review of studies. But these conclusions aren’t based on particularly strong data, the researchers say. “The most important finding from our review is that current practice of managing urerteric stones is based on poor-quality evidence, mostly from small trials with a lot of heterogeneity,” said lead investigator Ghulam Nabi, a lecturer in the Health Services Research Unit of the University of Aberdeen in Scotland. The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic. The reviewers found six trials, involving 833 adults, that compared two minimally invasive kidney stone therapies: uretoscopy and extracorporeal shock wave lithotripsy.

In ureteroscopy, a surgeon passes a thin viewing instrument into the ducts that carry urine from the kidney. Once a kidney stone is located the urologist typically removes the crystalline mass with forceps or a “basket” instrument. The other treatment, extracorporeal shock wave lithotripsy, uses sound waves to break each kidney stone into small pieces. The pieces later travel through the urinary tract and pass painlessly from the body. The reviewed trials compared several different health outcomes: whether or not the patient was free of kidney stones, the need for additional treatment, therapy complications and length of hospitalization. Results gathered three or four months after treatment suggest that surgery outperformed sound wave therapy to completely clear kidney stones. But, the authors said that the success of the sound wave treatment varied depending on the kind of lithotripter, or shock wave machine that was used. Overall the review concludes that people treated with ureteroscopy achieve a higher stone-free rate, but have a longer hospital stay and more complications, although most problems were minor.

Science Daily
April 3, 2007

Original web page at Science Daily

Physicians have an effective new option for treating atrial fibrillation, a common irregular heart rhythm that can cause stroke. Heart surgeons at Washington University School of Medicine in St. Louis have developed and tested a device that radically shortens and simplifies a complex surgical procedure that has had the best long-term cure rate for persistent atrial fibrillation. The simplified procedure is termed Cox-maze IV, and the surgeons believe it can replace the older “cut and sew” Cox-maze III in which ten precisely placed incisions in the heart muscle created a “maze” to redirect errant electrical impulses. “This technology has made the Cox-maze procedure much easier and quicker to perform,” says Ralph Damiano Jr., M.D., the John Shoenberg Professor of Surgery and chief of cardiac surgery at the School of Medicine and a cardiac surgeon at Barnes-Jewish Hospital. “Instead of reserving the Cox-maze procedure for a select group of patients, we would urge use of this device for virtually all patients who have atrial fibrillation and are scheduled for other cardiac surgery.”

The device is a clamplike instrument that heats heart tissue using radiofrequency energy. By holding areas of the heart within the jaws of the device, surgeons can create lines of ablation, or scar tissue, on the heart muscle. In the older Cox-maze III procedure, the lines of ablation were made by cutting the heart muscle, sewing the incisions back together and letting a scar form. The ablation lines redirect the abnormal electrical currents responsible for atrial fibrillation, an irregular heart rhythm in which the upper heart chambers or atria wriggle like a bag of worms. The Cox-maze procedure was developed at the University in 1987. In their latest clinical study, reported in the February issue of the Journal of Thoracic and Cardiovascular Surgery, University surgeons showed that Cox-maze IV is just as effective as Cox-maze III for curing atrial fibrillation, yet takes one-third the time to perform.

“The older Cox-maze procedure was a very complicated operation, and very few surgeons were willing to do it,” Damiano says. “So we started working on new technology and helped develop an effective ablation device that simplifies the procedure. Not only is Cox-maze IV shorter, but with the new device the procedure is also much safer because there’s a much lower risk of bleeding.” Atrial fibrillation affects more than 2.2 million people in the United States and can cause fatigue, shortness of breath, exercise intolerance and palpitations. Compared to those without atrial fibrillation, those with the disorder are five times more likely to suffer from stroke and have up to a two-fold higher risk of death. For some patients, medications can control the abnormal heart rhythms and the risk of clotting associated with atrial fibrillation, but unlike the Cox-maze procedure, the drugs do not cure the disorder. Damiano says their most recent study of Cox-maze IV is unique because the surgeons carefully matched the age, sex and cardiac conditions of a group of patients who underwent Cox-maze III in the past with patients undergoing Cox-maze IV. “This is the first documentation of the effectiveness of the ablation devices compared to the incisions of the Cox-maze III,” Damiano says. “This operation is very effective, and we now use the Cox-maze IV technique exclusively.”

Science Daily
March 6, 2007

Original web page at Science Daily

In an era when lung cancer remains the most lethal cancer, accounting for more deaths than colon, breast and prostate cancer combined — and surgery, when possible, is the most effective treatment — Mayo Clinic surgeons have proposed a system of lung surgery quality indicators for surgeons and the public as a method to demonstrate best practices for obtaining positive patient outcomes. Mayo Clinic surgeons believe the process is necessary because no other method currently exists to measure the quality of care received by patients undergoing lung surgery. Death rates following surgery are reported. However, because they aren’t adjusted for factors such as patient age and disease severity, they don’t tell the whole story. To overcome this lack of risk adjustment in death rate data, the Mayo Clinic team proposed patient-centered processes that should occur prior to, during and after surgery to assure the likelihood of best surgical outcomes.

“There are certain processes that we can measure and report that clearly indicate whether a patient has received high-quality care around the time of their lung operation,” explains Stephen Cassivi, M.D., Mayo Clinic thoracic surgeon. Dr. Cassivi presented a list of proposed patient-centered quality indicators for lung surgery at the 43rd Annual Meeting of the Society of Thoracic Surgeons this week in San Diego. “Knowing this data can help the patient decide about the care they are about to receive and where to go to receive that care — and equally important, this knowledge can help chest surgery programs improve their quality of care by concentrating on identified weaknesses,” says Dr. Cassivi. “Creating standards through measures of process will allow for directed quality improvement initiatives across all surgical centers.” To find the clearest and most meaningful measures to evaluate lung surgery quality, the Mayo Clinic team analyzed the care of 606 lung surgery patients who underwent 628 lung surgeries at Mayo Clinic during one year. The patients’ average age was 65.8 years and ranged from 2 to 93 years. From the analysis, the following list emerged for processes that should occur prior to surgery because of their potential contribution to positive patient outcomes: Pulmonary function testing; electrocardiogram; smoking history documented; smoking cessation therapy offered to those patients still smoking prior to surgery; appropriate preoperative staging of cancer.

In addition, the Mayo Clinic team identified post-lung surgery practices that improve patient outcome. These include: use of incentive spirometry — a simple breathing exercise meant to increase lung capacity and prevent postoperative pneumonia; timely response to heart rhythm disturbances; defined measures to prevent venous clots (deep vein thrombosis); documented timely attention to pain control for patients’ comfort; and follow-up care planning with the patient prior to discharge from the hospital. “All of these measures are patient-centered and relevant to the clinical improvement of the patient undergoing lung surgery, and they can be easily documented and assessed,” Dr. Cassivi says. The Mayo Clinic thoracic surgery team suggests that surgeons and hospitals adopt them as standard protocol.

Mayo Clinic will work to formalize its proposal with the Society of Thoracic Surgeons. Adopting these quality process measures as standards and compiling data regarding adherence to these standards could be accomplished using the Society of Thoracic Surgeons national general thoracic surgery database. Says Dr. Cassivi: “Our Mayo Clinic experience shows that if the whole general thoracic surgery team — from surgeons, to nurses, nurse educators, physician assistants, physical therapists — uses these process measures as indicators of a high quality of care, areas for improvement can be identified and improved in a timely fashion. If all practices used these indicators, the huge variability in care of lung surgery patients could be reduced and overall quality increased.”

Mayo Clinic
February 20, 2007

Original web page at Mayo Clinic

An increase among women electing to have caesarean sections in recent years has been due in large part to a concern that giving birth vaginally will lead to a fallen bladder and uterus in later life, and the issue has been hotly debated in the medical community. New research from the University of Michigan Health System establishes one of the strongest connections yet discovered between muscle damage that can occur during vaginal deliveries and pelvic organ prolapse, a condition that causes the uterus, bladder or bowel to fall down later in a woman’s life. This is a very common problem and requires surgery in more than 200,000 women each year. Rates were particularly high when forceps had been used to assist the delivery. Even so, the researchers caution against using these findings as support for more elective C-sections because that would result in numerous women having an operation they do not need. Rather, they say, the study results should be used to help determine how to prevent these injuries in the first place.

The study — appearing in the February issue of the journal Obstetrics & Gynecology — found major defects of the levator ani, an important muscle that supports the bladder and uterus, among 55 percent of women with prolapse and just 16 percent of women who don’t have prolapse. “Our findings are an important step forward in the search to identify what causes pelvic organ prolapse and subsequent difficulties with other problems, such as incontinence,” says lead author John O. L. DeLancey, M.D., the Norman F. Miller Professor of Obstetrics and Gynecology at the U-M Medical School and director of pelvic floor research. “The next step is for researchers to look at ways of preventing and treating these injuries of the levator ani muscle in order to reduce the rate of pelvic organ prolapse later in life,” he says.

Pelvic organ prolapse can mean the falling of the bladder, uterus, vagina or lower bowel. One of the most common effects of the condition is urinary incontinence — that is, the inability to control the release of urine. Many women with prolapse experience a protrusion or bulging in the vaginal area. The condition is common; one of nine women has surgery to correct prolapse and other pelvic floor disorders in her lifetime.The U-M researchers studied 151 women with prolapse and compared them with 135 women who do not have prolapse. Magnetic resonance imaging was used to determine the extent of damage to the levator ani muscles. The women’s vaginal closure force at rest and while contracting her pelvic muscle also was measured.

Women with prolapse were found to have a much higher rate of major levator ani damage than women without prolapse (55 percent compared with 16 percent). When they asked women to contract their muscles, the muscles were 40 percent weaker in women with prolapse. In addition, about 52 percent of the women in the study with prolapse recalled having forceps used during childbirth, nearly twice the amount (about 27 percent) of women in the study who do not have prolapse who remembered that forceps were used. Thirty-one percent of women with prolapse reported a family history of the condition, compared with 13 percent of the women without prolapse.

Science Daily
February 20, 2007

Original web page at Science Daily

According to a review of the latest clinical trials, coronary artery bypass surgery performed on a beating heart, without the aid of a heart-lung machine, is a safe option that leads to fewer negative side effects for bypass patients. This review is featured in Journal of Cardiac Surgery. “Previously, it was more common for doctors to perform artery bypass surgery on the heart by stopping the heart and passing the blood through a heart-lung machine,” says author Dr. Shahzad Raja. “However, this process frequently leads to ‘whole body inflammation,’ which includes complications such as brain swelling, heart arrhythmia and infections.” According to Raja, performing the surgery on the beating heart, while more technically challenging for the surgeon, keeps these side effects low and allows for a quicker recovery.

“If the surgeons are skilled enough to perform the surgery without stopping the heart, it can be offered to high-risk patients who would not be likely to survive the side effects of the traditional stopped-heart method,” says Raja. “For this reason, quality training needs to be provided for those surgeons who wish to offer this option to their patients.”

Science Daily Health & Medicine
February 20, 2007

Original web page at Science Daily Health & Medicine

A Mayo Clinic surgical team has found that using a 3-Tesla MRI in surgical decision making provides a new level of capability to predict surgical outcomes that improves patient care by minimizing the potential for unsuccessful tumor-removal surgeries. The Mayo Clinic report appeared in the December issue of the Journal of Neurosurgery www.thejns-net.org/jns/issues/current/toc.html. In their report, Mayo physicians describe a case study of five patients. Four had neurofibromatosis, a condition with a predisposition to nerve-related tumors. All patients suffered from growths called “sciatic notch dumbbell-shaped” tumors. The tumors were benign, but resulted in neurologic dysfunction and disabling pain. “In the past, if surgeons couldn’t tell prior to surgery where the exact location of the large tumor was in relation to the sciatic nerve, it meant they couldn’t predict in which cases surgery could be performed safely,” explains Robert Spinner, M.D., the lead neurosurgeon on the Mayo Clinic team.

The team used an advanced magnetic resonance imaging (MRI) system performed on a 3-Tesla magnet to help identify suitable candidates for a difficult tumor-removal surgery. A Tesla is a unit of magnet strength. A 3-Tesla is one of the strongest commercially available. A standardized surgical approach for safe and complete removal of sciatic notch dumbbell-shaped tumors has been problematic for at least three reasons. These tumors are: relatively rare and therefore hard to study; anatomically difficult to reach and remove without injuring the main sciatic nerve; difficult to visualize before surgery with enough detail to distinguish tumor boundaries from nerve.

The current Mayo Clinic report begins to change this situation by documenting a new multidisciplinary approach for obtaining the desired favorable surgical outcomes. Surgeons need an accurate picture of how and whether they can remove a tumor while protecting a nerve. Otherwise, patients may be exposed to the risks of surgery without achieving surgical benefits if the tumor is inoperable because complete removal would damage a nerve. “Our experience demonstrates the advantages of predictive imaging at the outset,” says Dr. Spinner. “With an integrated team of surgeons from three specialties, and an experienced radiologist specializing in advanced peripheral nerve imaging using the 3-Tesla MRI, we have devised an approach that minimizes unsuccessful tumor-removal surgeries.”

With the 3-Tesla MRI images, Mayo Clinic surgeons from three specialties — neurosurgery, colorectal and orthopedic surgery — obtained sufficiently detailed pictures of the tumor and nerve relationship before surgery in all five cases to accurately predict which patients would benefit from surgery. In three cases the tumor was predicted to be distinct from the main sciatic nerve, and the tumor was safely removed. All three patients experienced relief from pain and had no recurrent growth one year after surgery. In the other two cases, the tumor was predicted to be so entwined in the nerve that surgery would have damaged the nerve. Those patients did not undergo surgery. Dr. Spinner said the team will continue to refine the approach to improve the care that these patients receive. “This new technology allows a multidisciplinary approach to be performed safely in these rare tumors that were once considered unresectable,” he says. “In addition, the same techniques that we have developed have tremendous applications to many patients who have peripheral nerve tumors in more common locations.”

Mayo Clinic
January 23, 2007

Original web page at Mayo Clinic

Drawing on advances in robotics and computer technology, Johns Hopkins University researchers are designing new high-tech medical tools to equip the operating room of the future. These systems and instruments could someday help doctors treat patients more safely and effectively and allow them to perform surgical tasks that are nearly impossible today. The tools include a snakelike robot that could enable surgeons, operating in the narrow throat region, to make incisions and tie sutures with greater dexterity and precision. Another robot, the steady-hand, may curb a surgeon’s natural tremor and allow the doctor to inject drugs into tiny blood vessels in the eye, dissolving clots that can damage vision. Working closely with physicians from the Johns Hopkins School of Medicine, the center’s engineers and computer scientists are building robotic assistants intended to enhance a surgeon’s skills. They are devising detailed visual displays to guide a doctor before and during a difficult medical procedure and planning digital workstations that would give the physician instant access to an enormous amount of medical information about the patient.

Because most of the new medical tools are linked to computers, their work can easily be recorded. Later, these records would be checked against data describing how well a patient responded to the treatment. From this review, doctors could learn which techniques and procedures were most effective. “We could produce the equivalent of a flight-data recorder for the operating room,” said Russell H. Taylor, a professor of computer science and director of the center. The emphasis is on futuristic technology, but “we’re not trying to replace or automate surgeons,” Taylor insists. “We want to work in partnership with surgeons to help them do their work more effectively. Human hands are remarkable, but they have limitations. There are times when it would be useful to have a ‘third hand,’ and we can provide that. Sometimes a surgeon’s fingers are too large to work in a small confined space within the body. We can help by building tools that act like inhumanly small and highly dexterous hands.”

One promising example is the team’s snakelike robot. Currently, a doctor performing throat surgery must insert and manually manipulate long inflexible tools and a camera into this narrow passageway. The snakelike robot would provide an alternative. It could enter the throat with two thin rods tipped with tentacle like tools capable of moving with six degrees of freedom. If directed, the tools can bend easily into an S-curve. During surgery, a doctor would sit at a robotic workstation and peer into eyepieces that display a three-dimensional view of the operating site. The doctor would then manoeuvre the controls to guide the movement of the robot. The prototype is made of nonmagnetic metals so that it can be used safely near magnetic imaging equipment. The tools’ movements are nimble because sophisticated software can make up to 100 adjustments per second.

The steady-hand system, also devised by a Johns Hopkins team, was built to help with another challenging task: microsurgery. At this scale, even the best surgeons display some tremor in their hands. Yet the slightest uncontrolled movements can be troublesome during surgery on microscopic structures, such as tiny blood vessels in the eye. To address this problem, the steady-hand robot can grasp a needle and move it carefully in tandem with the surgeon in a technique called cooperative manipulation. In tests of the device, the researchers have successfully injected a liquid into a chicken embryo’s blood vessels, resembling structures in the human eye. “The steady-hand could allow a surgeon to make very precise and accurate micro-movements without tremor,” Taylor said. Before they are used on human patients, both the snakelike robot and the steady-hand system will require perhaps five more years of lab testing and prototype advancement. Still, Taylor believes both have a good chance of eventually joining more traditional tools in hospital operating rooms. “What makes this work particularly rewarding,” he said, “is that we have the opportunity to do cutting-edge engineering that can help people in a very direct way.”

Science Daily
January 9, 2007

Original web page at Science Daily

New research by Queensland University of Technology is helping scientists better understand how bone cells work and may one day lead to the development of technology that can speed up the time it takes to heal fractured and broken bones. Recent graduate Dr Gwynne Hannay has built a gadget capable of promoting bone cell formation in the laboratory. Dr Hannay said his device replicated the mechanical and electrical stimulants which occurred naturally in the body to repair fractured and broken bones. “This device is about trying to grow bone tissue in the same environment our body grows bones. I have taken bone cells and put them in the physical environment they would experience in the body, and then varied the stimulants to extract a beneficial environment for tissue growth,” he said.

Dr Hannay’s research has advanced the understanding of how bone cells can be stimulated to heal factures and has for the first time combined the artificial reproduction of both mechanical and electrical stimulants.”Previous research has looked at both of these stimulants individually, but not together, neglecting the fact that both are occurring in normal healthy bone during fracture healing” He said by combining the two stimulants, a synergistic effect was produced. “That means when you apply both the mechanical and electrical stimulants together a result greater than the sum of the two stimulants applied individually is achieved. It creates a greater output,” he said. Dr Hannay said that unfortunately when bones fractured or broke, especially in older people, the healing process could stall.

“We find bones can get half way through the healing process but won’t heal properly and with an aging population this is a growing problem for orthopaedic surgeons to accommodate and one that is not easily solved with current methodologies,” he said. “In the future we might be able to make a device utilising these combined stimulants that could be attached to the body and help heal the bone.” Additionally, normal fractures that would otherwise heal successfully could be accelerated with the use of these stimulants. Dr Hannay said normal fractures in young, healthy people took approximately six to eight weeks to heal. “It might be possible to significantly reduce the healing time. That would be the goal.”

Science Daily
December 19, 2006

Original web page at Science Daily

A single dose of antibiotics prior to surgery appears to prevent infections occurring at the surgical site as effectively as a 24-hour dosing regimen, and with reduced antibiotic costs, according to an article in the November issue of Archives of Surgery, one of the JAMA/Archives journals. Infections remain an important complication of surgical procedures despite increased knowledge about prevention and technological advances in modern surgery, according to background information in the article. Prophylactic antibiotics–preventive antibiotics given before surgery–have been shown to decrease the occurrence of infection at the site of the surgery. However, due to rising health care costs and concerns about antimicrobial resistance, hospitals have been under pressure to use fewer antibiotics. Most guidelines for the use of prophylactic antibiotics recommend using only one dose prior to surgery; however, surgeons might not comply with this recommendation, sometimes giving patients more than one dose or using broad-spectrum (targeting many types of bacteria) rather than the recommended narrow-spectrum drugs.

Silvia Nunes Szente Fonseca, M.D., M.P.H., Hospital São Francisco, Ribeirão Preto, São Paolo, Brazil, and colleagues studied infection rates before and after the implementation of a one-dose prophylactic antibiotic protocol at a local hospital. “We previously described the successful implementation of an antibiotic prophylaxis program in our hospital, discontinuing prophylactic antibiotic usage after 24 hours and correcting the timing of the first dosage,” the authors write. “We decided to reduce all antibiotic prophylaxis to one dose because this measure could safely promote savings for our institution.” Under the new protocol, for most procedures, patients are given one 1-gram dose of the antibiotic cephazolin at the same time anesthesia is administered. The protocol was approved by surgeons prior to implementation; education was provided to surgical and medical staff. To assess the effectiveness of this approach, the researchers examined infection rates and costs for 6,140 consecutive patients who had surgery between February 2002 and October 2002 and 6,159 consecutive patients who had surgery between December 2002 and August 2003, following the implementation of the one-dose protocol.

The correct protocol was followed in 6,123 (99 percent) of the surgeries performed after the new guidelines were implemented. Surgical site infections occurred in 127 (2 percent) of surgeries performed under the 24-hour protocol and 133 (2.1 percent) performed under the one-dose protocol. The number of vials of cephazolin purchased decreased from 1,259 in the first time period to 467 in the second, a 63 percent decline that represented a monthly cost savings of $1,980 for this drug alone. The cooperation and encouragement of hospital administration and clinical staff, as well as educational efforts, contributed to the success of the new protocol, the authors write. “We were able to demonstrate that one-dose prophylaxis is feasible,” they conclude. “In this era of restricted hospital budgets and increased bacterial resistance, one-dose prophylaxis may provide a way to improve performance by lowering costs.”

Science Daily Health & Medicine
December 19, 2006

Original web page at Health & Medicine

For many patients with urinary stone disease, treatment with a calcium-channel blocker or an alpha blocker can greatly improve their likelihood of passing their urinary stones, which may help these patients avoid surgery, according to an analysis by the University of Michigan Health System. Urinary stone disease is highly prevalent, afflicting 13 percent of men and 7 percent of women in the United States. While many urinary stones are treated today with minimally invasive techniques, there is growing evidence to suggest that medications can be an effective treatment. Calcium-channel blockers and alpha blockers are used commonly for management of high blood pressure and enlarged prostates. In this study, published in the Lancet, researchers identified and analyzed numerous studies and found that both medications were a successful alternative for treatment of an acute urinary stone episode.

“Surgery is still a necessary treatment for many patients with urinary stones,” says senior author Brent K. Hollenbeck, M.D., assistant professor of urology at the U-M Medical School and Comprehensive Cancer Center. “However, for many people, a more conservative approach beginning with a trial of a calcium-channel blocker or an alpha blocker is proving to be efficacious.” Researchers looked at articles about this issue and ultimately analyzed nine trials that included 693 patients. The trials examined the use of calcium-channel blockers or alpha blockers to assist with the passage of urinary stones. In all, they found that patients treated with one of the medications had a 65 percent greater chance of passing the stones spontaneously than patients not given these drugs. “This suggests that treatment with these medications is an important first step for patients with an acute urinary stone episode,” says lead author John M. Hollingsworth, M.D., fifth-year surgery resident with the Department of Urology at the U-M Medical School. Hollingsworth also notes that the cost of medical treatment for urinary stones would be far lower than with surgery.

Science Daily
October 24, 2006

Original web page at Science Daily

French doctors carried out the world’s first ever operation on a human in zero gravity on Wednesday, using a specially adapted aircraft to simulate conditions in space. During a 3-hour flight from Bordeaux in southwest France, the team of surgeons and anaesthetists successfully removed a benign tumour from the forearm of a 46-year-old volunteer. The experiment was part of a programme backed by the European Space Agency (ESA) to develop techniques for performing robotic surgery aboard the International Space Station or at a future Moon base. “We weren’t trying to perform technical feats but to carry out a feasibility test,” said team leader Dominique Martin after the flight. “Now we know that a human being can be operated on in space without too many difficulties.”

The custom-designed Airbus 300 aircraft – dubbed Zero-G – performed a series of parabolic swoops, creating about 20 seconds of weightlessness at the top of each curve. The process was repeated 32 times. Strapped inside a custom-made operating block, three surgeons and two anaesthetists worked during these brief bursts, using magnets to hold their instruments in place around the patient’s stretcher. The patient, Philippe Sanchot, told reporters the operation was “really no big deal”, although he said he was lifted “two or three centimetres” off the operating table each time zero gravity kicked in. “There were no surprises because we had rehearsed this over and over.” Martin said the experiment had confirmed that their equipment was suitable for use on board the International Space Station. “Operating in space is not going to pose a problem – except perhaps for vascular surgery,” he said. “We deliberately chose an operation that could be interrupted and where there was no large-scale bleeding, because it only involved surface tissues.” “If we’d had two hours of zero gravity at a stretch, we could have removed an appendix,” Martin said.

A similar experiment was carried out in October 2003 but the operation then was to mend a 0.5-millimetre-wide artery in a rat’s tail. The next phase of the programme is to carry out a remote-controlled operation using a robot whose commands are sent from the ground via satellite. This experiment should take place within a year, Martin said. Anaesthetist Laurent de Coninck said that zero-gravity surgery offered huge promise for space exploration, although at first it would be limited to treating simple injuries. World space agencies hope that by 2020 a permanently inhabited base can be established on the Moon to conduct research, exploit lunar resources and learn to live off the lunar land. Such a base would also test technologies for voyages to Mars.

New Scientist
October 10, 2006

Original web page at New Scientist

U.S. scientists say they’ve found a gene called SUMO1, that, when underexpressed, can cause cleft lip and palate — one of the most common birth defects. Since the SUMO1 gene encodes a small protein that’s attached to the protein products of at least three previously discovered “clefting” genes, in essence linking them into or near a shared regulatory pathway and now hotspot for clefting. “The big challenge for research on cleft lip and palate is to move from studying individual genes to defining individual protein networks,” said Dr. Richard Maas, a scientist at Brigham and Women’s Hospital and Harvard University Medical School and senior author of the paper. “By protein network, I mean a nexus of proteins that interact in a highly regulated way,” he added. “It’s at this dynamic, real-time level that science will begin to see the big picture and tease out more of the needed insights to understand and hopefully eventually prevent cleft lip and palate in newborns.” The study appears in the current issue of the journal Science.

Science Daily
October 10, 2006

Original web page at Science Daily

The use of anti-inflammatory drugs following hip replacement surgery could do more harm than good, according to a new study co-coordinated by The George Institute for International Health in association with orthopedic centres throughout Australian and New Zealand. The results of the study designed to determine the long-term benefits and risks of anti-inflammatory drugs in patients undergoing hip replacement surgery were published today in the British Medical Journal. The study specifically measured the effects of a short post-operative course of anti-inflammatories on the development of ‘ectopic’ bone formation related pain and disability, six to twelve months after surgery.

“Ectopic bone is abnormal bone that can form in the soft tissues around the operated hip. This occurs in more than one third of all patients in the months after hip replacement surgery,” explained, Dr Marlene Fransen Head, Musculoskeletal Program at The George Institute and Principal Investigator of this study. Many surgeons prescribe anti-inflammatory drugs in the immediate post-operative period to avoid this outcome, or simply as part of a pain management strategy. While the researchers found the use of post-operative ibuprofen, a common anti-inflammatory drug, did indeed greatly reduce the risk of ectopic bone formation, patients reported no greater reductions in hip pain or physical disability six to twelve months after surgery, compared with those not taking the drug. However, they also found evidence suggesting there may be an increased risk of major bleeding events in those taking the drug.

“For this reason, our study shows that recommending a routine course of an anti-inflammatory drug following hip replacement surgery, is not justified,” Chronic osteoarthritis of the hip is common among Australians aged 60 years or older and total hip replacement surgery is a well-established and highly effective treatment. Whilst joint replacement surgery greatly reduces chronic hip pain and improves physical function in most, residual symptoms are common. Over 900 patients from 20 orthopedic surgery centres across Australia and New Zealand participated in this study, half of whom were allocated to receive ibuprofen, a common anti-inflammatory drug, for 14 days commencing immediately after surgery. “These results provide further evidence that guidelines for routine clinical care in surgery must be based on clinically important outcomes. Without such evidence, the widespread use of routine anti-inflammatory-based treatment after major orthopaedic surgery may well result in harm rather than benefit,” Dr Fransen added.

Science Daily
September 26, 2006

Original web page at Science Daily

If you are scheduled for reconstructive orthopaedic surgery, or need a new heart valve, you might want to check where the tissue you are given has come from. For the second time this year, a firm supplying body parts for surgery has been shut down by the US Food and Drug Administration, and more safety scandals are expected to emerge from this booming industry. The latest scare surrounds Donor Referral Services, based in Raleigh, North Carolina, which harvested body parts, including bone, tendons and heart valves, from corpses in funeral homes. FDA inspectors found numerous safety breaches, including a failure to follow procedures intended to prevent bacterial contamination, and errors in the medical histories of the donors. The FDA is still investigating, and will not comment on how many patients received tainted tissues.

This incident follows a scandal surrounding Biomedical Tissue Services of Fort Lee, New Jersey, which closed in February after similar safety breaches. Company staff were called “bodysnatchers” in media reports, after harvesting tissues from donors without proper consent, and four men now face criminal charges. Retrieving, processing and distributing body parts is a massive industry, with annual revenues in the US exceeding $1 billion. Yet the safety regulations breached by the two firms did not come into effect until May last year. “We’re now peeling the onion and finding where it’s rotten,” says Areta Kupchyk, a lawyer who helped write the regulations while at the FDA.

The European Union has also started regulating the tissue industry. Since April this year, organisations handling human tissues for use in surgery must be licensed and are subject to inspection. So far, no major problems have emerged with European operators. The US scandals may have a global reach nonetheless. Australian patients were among those given tissues harvested by Biomedical Tissue Services. Also, Don Keenan, a lawyer in Atlanta, Georgia, is representing patients in Germany and Austria who claim they were infected by other tissues exported from the US.

New Scientist
September 12, 2006

Original web page at New Scientist

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

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

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

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