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Potential new tool for brain surgeons

One of the primary ways of treating brain cancer is surgically removing the tumors. The risk of this sort of procedure is obvious — it involves cutting away tissue from the brain, potentially severing nerve fibers and causing neurological damage. MRI and CT scans can reveal the extent of tumors, but only prior to surgery. These techniques rely on large instruments that cannot be used in the operating room, and during the operation the brain may relax and move, forcing surgeons to adjust where they are cutting to minimize the damage to the brain tissue. During surgery, doctors make these adjustments by asking their patients to perform certain tasks while electrically stimulating parts of the brain bordering where they plan to cut. The electrical stimulation inhibits brain function in that region, revealing whether losing that tissue would cause permanent damage. Although slow, this is a good way to detect and protect critical areas of the brain.

Now Paul Hoy and his colleagues at the University of Southampton in England are developing a rapid and highly sensitive method for measuring brain function across the entire area during surgery. The method is based on observing blood flow in the brain. Active brain regions have increased blood flow, and this change can be observed by looking at light reflected off the brain because hemoglobin, the protein that ferries oxygen within the bloodstream, will absorb light differently depending on whether it carries oxygen or not. Recently Hoy and his colleagues measured this signal on four people undergoing brain surgery and showed that their results agreed with the electrical stimulation. They hope that the technique will one day provide information quickly for neurosurgeons, and they are now collecting data that will lead to a clinical trial designed to test how effective the technique is.

Science Daily
October 28, 2008

Original web page at Science Daily

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Research suggests doctors should consider kidney-sparing surgery

A study of almost 1,500 kidney cancer patients treated at Memorial Sloan Kettering Cancer Center suggests that surgery to spare as much kidney tissue as possible may improve overall survival in patients who also have reduced kidney function at the time their cancer is diagnosed. The finding is significant because both kidney cancer and decreased kidney function appear to be increasing. In patients who have the combination of kidney cancer and lowered kidney function, doctors should consider tissue-sparing surgery – versus complete removal – whenever it is technically feasible,” said Joseph Pettus, M.D., lead author and now an assistant professor of urology at Wake Forest University School of Medicine. “Currently this option is significantly underused.” Reporting in the Mayo Clinic Proceedings, a peer-reviewed medical journal, researchers found that among patients having surgery for kidney cancer, those who also had severely impaired kidney function were almost three times more likely to die than patients with normal kidney function.

Impaired kidney function can sometimes be related to the cancer itself. But impaired function can also be caused or compounded by a variety of other factors, including diabetes, hypertension and vascular disease. Impaired kidney function itself – even without a diagnosis of cancer – is related to increased risk of death and hospitalization. Surgery to remove a malignant tumor can further impair kidney function because the loss of kidney tissue affects kidney function over time. Researchers at Memorial Sloan Kettering had previously found that patients whose kidneys were completely removed were almost 12 times more likely to develop significantly impaired function in the remaining kidney than patients whose organs were partially removed. The study involved an analysis of data from kidney cancer patients treated during a 10-year period. Pettus conducted the research with colleagues at Sloan Kettering before moving to Wake Forest.

The research was based on the hypothesis that kidney cancer patients with reduced kidney function prior to surgery would have lower survival rates than cancer patients with normal kidney function. The researchers excluded patients whose disease had spread to the lymph nodes or other parts of the body. They found that median beginning levels of kidney function in all patients decreased during the 10-year period by about 10 percent. Compared to those with normal kidney function, patients who began with moderately reduced function were 150 percent more likely to die from any cause. Those with severely reduced function were almost three times (280 percent) more likely to die. Pettus said the findings suggest that obesity and related diseases that affect kidney function may be contributing to the rising death rates from kidney cancer. Overall death rates increased 323 percent among kidney cancer patients between 1983 and 2002 – despite the fact that the disease is being detected earlier. He said that rising rates of kidney cancer – combined with a decline in kidney function – is almost a “perfect storm” scenario which may explain the decrease in survival, even among patients with early stages of kidney cancer.

“These findings underscore the importance of considering baseline kidney function when devising treatment plans for patients with kidney tumors,” said Pettus. He said the findings raise concerns that surgery may result in more medical harm than benefit to treating the cancer. “Our data beg the question of whether patients with moderate to severe kidney disease and small tumors might be better managed through tissue-sparing techniques or a ‘watchful waiting’ approach,” said Pettus. “Completely removing the kidney may result in more harm than good, particularly in elderly patients with small tumors and other medical problems. For these patients, careful surveillance may be a legitimate option with surgery reserved for cases where the tumor increases in size.” Research has shown that for tumors that are 7 cm or less, partial removal of the kidney provides equal cancer control to total removal. However, partial removal accounted for only 7.5 percent of kidney surgeries between 1988 and 2002. And for smaller tumors, only 20 percent were treated with partial removal of the kidney.

Science Daily
October 14, 2008

Original web page at Science Daily

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Johns Hopkins researchers suppress ‘hunger hormone’

Johns Hopkins scientists report success in significantly suppressing levels of the “hunger hormone” ghrelin in pigs using a minimally invasive means of chemically vaporizing the main vessel carrying blood to the top section, or fundus, of the stomach. An estimated 90 percent of the body’s ghrelin originates in the fundus, which can’t make the hormone without a good blood supply. “With gastric artery chemical embolization, called GACE, there’s no major surgery,” says Aravind Arepally, M.D., clinical director of the Center for Bioengineering Innovation and Design and associate professor of radiology and surgery at the John Hopkins University School of Medicine. “In our study in pigs, this procedure produced an effect similar to bariatric surgery by suppressing ghrelin levels and subsequently lowering appetite.” Reporting on the research in the September 16 online edition of Radiology, Arepally and his team note that for more than a decade, efforts to safely and easily suppress grehlin have met with very limited success.

Bariatric surgery – involving the removal, reconstruction or bypass of part of the stomach or bowel – is effective in suppressing appetite and leading to significant weight loss, but carries substantial surgical risks and complications. “Obesity is the biggest biomedical problem in the country, and a minimally invasive alternative would make an enormous difference in choices and outcomes for obese people,” Arepally says. Arepally and colleagues conducted their study over the course of four weeks using 10 healthy, growing pigs; after an overnight fast, the animals were weighed and blood samples were taken to measure baseline ghrelin levels. Pigs were the best option, he says, because of their human-like anatomy and physiology. Using X-ray for guidance, members of the research team threaded a thin tube up through a large blood vessel near the pigs’ groins and then into the gastric arteries supplying blood to the stomachs. There, they administered one-time injections of saline in the left gastric arteries of five control pigs, and in the other five, one-time injections of sodium morrhuate, a chemical that destroys the blood vessels. The team then sampled the pigs’ blood for one month to monitor ghrelin values. The levels of the hormone in GACE-treated pigs were suppressed up to 60 percent from baseline. “Appetite is complicated because it involves both the mind and body,” Arepally says. “Ghrelin fluctuates throughout the day, responding to all kinds of emotional and physiological scenarios. But even if the brain says “produce more ghrelin,” GACE physically prevents the stomach from making the hunger hormone.”

EurekAlert! Medicine
September 30, 2008

Original web page at EurekAlert! Medicine

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Helping tumor cells not to stick so the wound during surgical removal

Sometimes during surgery to remove a tumor, cells become detached from the bulk of the tumor. In a small number of cases, these tumor cells stick to cells at the site of the surgical wound and go on to form a secondary tumor, having an enormous negative impact on the survival and quality of life of the patient. New data, generated by Marc Basson and colleagues, at the John D. Dingell VA Medical Center and Wayne State University, Detroit, using a mouse model of surgery to remove a colon cancer tumor, suggest that perioperative treatment with a drug known as colchicine might decrease the incidence of tumor formation at the site of the surgical wound. When colon cancer tumor cells are exposed to high pressure they exhibit an increased ability to stick to other cells. In the study, to mimic the conditions of surgery, the authors removed colon cancer cells from one mouse, exposed them to high pressure in vitro, and then transplanted them into a second mouse that they monitored for the development of tumors at the site of the surgical wound.

The most important observation made was that if the mice from which the colon cancer cells came from were treated perioperatively with colchicine there was a dramatic decrease in the number of tumors that formed at the site of the surgical wound in the second mouse. As in vitro exposure of tumor cells from breast and head and neck cancers to high pressure also increases their ability to stick to other cells it is possible that these data might have implications in several clinical settings.

Science Daily
September 2, 2008

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Gallbladder removed through uterus without external incisions

In April of last year, surgeons at NewYork-Presbyterian Hospital/Columbia University Medical Center made headlines by removing a women’s gallbladder through her uterus using a flexible endoscope, aided by several external incisions for added visibility. Now, they have performed the same procedure without a single external incision in what surgeons report may be the first surgery of its kind in the United States. Led by Dr. Marc Bessler the procedure is offered as part of an ongoing clinical research trial and could prove to have advantages over traditional endoscopic surgery, including reduced pain, quicker recovery time and absence of visible scarring. Employing this technique, called NOTES (natural-orifice translumenal endoscopic surgery), the endoscope was inserted through a one-inch incision behind the uterus and into her body cavity. Using that scope, the gallbladder was detached and removed through the incision behind the uterus. The area where the gallbladder was removed was then sutured. The three-hour outpatient procedure was performed to treat painful gallstones, which form when bile in the gallbladder hardens into pieces of stone-like material. Removal of the gallbladder is necessary in persistent and painful cases. A small and non-essential organ, the gallbladder stores and releases bile as part of the digestive process.

“This procedure marks the culmination of 15 years of advances that have made surgery less invasive in order to improve safety and reduce recovery time,” says Dr. Bessler, director of laparoscopic surgery and director of the Center for Obesity Surgery at NewYork-Presbyterian Hospital/Columbia University Medical Center and assistant professor of surgery at Columbia University College of Physicians and Surgeons. Beginning in the late 1980s, surgeons pioneered laparoscopic techniques for gallbladder surgery. Instead of the traditional 10-inch abdominal incision necessary for traditional open surgery, surgeons operated by inserting a camera and surgical instruments through a few small incisions. Nine out of 10 gallbladder surgeries are now performed this way. Natural-orifice surgery has been mainly confined to treating conditions within the gastrointestinal tract. However, the NOTES approach now goes a step further with this surgery — into the patient’s abdominal cavity. “Internal incisions, such as in the uterus, are less painful and may allow for quicker recovery than incisions in the abdominal wall,” says Dr. Bessler.

Science Daily
August 19, 2008

Original web page at Science Daily

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Checking more lymph nodes linked to cancer patient survival

Why do patients with gastric or pancreatic cancer live longer when they are treated at cancer centers or high-volume hospitals than patients treated at low-volume or community hospitals? New research from Northwestern University’s Feinberg School of Medicine found that cancer patients have more lymph nodes examined for the spread of their disease if they are treated at hospitals performing more cancer surgeries or those designated as comprehensive cancer centers. Lymph node metastases (indicating the spread of cancer) have been shown to predict patients’ prognosis after cancer tissue is removed from the stomach or pancreas. If too few lymph nodes are examined for malignant cells, a patient’s cancer may be incorrectly classified, which alters the prognosis, treatment decisions and eligibility for clinical trials. “The differences in nodal evaluation may contribute to improved long-term outcomes at cancer centers and high-volume hospitals for patients with gastric and pancreatic cancer,” said Karl Bilimoria, M.D., lead author of the paper and a surgical resident at the Feinberg School.

Current guidelines recommend evaluating at least 15 regional lymph nodes for gastric and pancreatic cancer, according to the study. Researchers reported that patients at a high-volume hospital or a hospital designated as a National Cancer Institute comprehensive cancer center or as part of the National Comprehensive Cancer Network were more likely to have at least 15 lymph nodes evaluated than patients undergoing surgery at community or low-volume hospitals. “Every reasonable attempt should be made to assess the optimal number of lymph nodes to accurately diagnose stage disease in patients with gastric and pancreatic cancer,” said Bilimoria, who also is a research fellow at the American College of Surgeons. “The status of patients’ lymph nodes is a powerful predictor of their outcome.”
Source: Archives of Surgery.

Science Daily
August 5, 2008

Original web page at Science Daily

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Licking your wounds: Scientists isolate compound in human saliva that speeds wound healing

A report by scientists from The Netherlands identifies a compound in human saliva that greatly speeds wound healing. This research may offer hope to people suffering from chronic wounds related to diabetes and other disorders, as well as traumatic injuries and burns. In addition, because the compounds can be mass produced, they have the potential to become as common as antibiotic creams and rubbing alcohol. “We hope our finding is ultimately beneficial for people who suffer from non-healing wounds, such as foot ulcers and diabetic ulcers, as well as for treatment of trauma-induced wounds like burns,” said Menno Oudhoff, first author of the report.

Specifically, scientists found that histatin, a small protein in saliva previously only believed to kill bacteria was responsible for the healing. To come to this conclusion, the researchers used epithelial cells that line the inner cheek, and cultured in dishes until the surfaces were completely covered with cells. Then they made an artificial wound in the cell layer in each dish, by scratching a small piece of the cells away. In one dish, cells were bathed in an isotonic fluid without any additions. In the other dish, cells were bathed in human saliva. After 16 hours the scientists noticed that the saliva treated “wound” was almost completely closed. In the dish with the untreated “wound,” a substantial part of the “wound” was still open. This proved that human saliva contains a factor which accelerates wound closure of oral cells. Because saliva is a complex liquid with many components, the next step was to identify which component was responsible for wound healing. Using various techniques the researchers split the saliva into its individual components, tested each in their wound model, and finally determined that histatin was responsible. “This study not only answers the biological question of why animals lick their wounds,” said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal, “it also explains why wounds in the mouth, like those of a tooth extraction, heal much faster than comparable wounds of the skin and bone. It also directs us to begin looking at saliva as a source for new drugs.”

Science Daily
August 5, 2008

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First successful reverse vasectomy on endangered species performed at the National Zoo

Veterinarians at the Smithsonian’s National Zoo performed the first successful reverse vasectomy on a Przewalski’s horse (E. ferus przewalskii; E. caballus przewalskii—classification debated), pronounced zshah-VAL-skeez. Przewalksi’s horses are a horse species native to China and Mongolia that was declared extinct in the wild in 1970. Currently, there are approximately 1500 of these animals maintained at zoological institutions throughout the world and in several small reintroduced populations in Asia. This is the first procedure of its kind to be performed on an endangered equid species. The genes of Minnesota—the horse who underwent the surgery—are extremely valuable to the captive population of the species, which scientists manage through carefully planned pairings to ensure the most genetically diverse population possible. The horse was vasectomized in 1999 at a previous institution so that he could be kept with female horses without reproducing. He came to the National Zoo in 2006.

While surveying the captive North American population of Przewalski’s horses, scientists realized Minnesota’s genetic value. Based on his ancestry, he is the seventh most genetically valuable horse in the North American breeding program. Zoo scientists were confident that if they could successfully reverse the vasectomy, Minnesota would be able to sire a foal through natural mating. “The major challenge we faced was that this procedure had never been performed on an equid, let alone a critically endangered species,” said Dr. Budhan Pukazhenthi, a reproductive scientist at the National Zoo’s Conservation and Research Center in Front Royal, Va. “We had to develop all new protocols ourselves.” The team sought the expertise of Dr. Sherman Silber, a St. Louis-based urologist who pioneered microsurgery for reverse vasectomies in humans and had been successful in vasectomizing and then subsequently reversing vasectomies in South American bush dogs at the St. Louis Zoo.

“Although our team is very experienced in horse anesthesia and surgery, by using the specialized professional skills of Dr. Silber, we greatly increased the likelihood of success,” said Dr. Luis Padilla, associate veterinarian at the Conservation and Research Center. Silber, working with the Zoo’s team of veterinarians and reproductive scientists, first performed the operation on Minnesota in March 2007. That procedure proved unsuccessful, possibly due to the presence of scar tissue or the fact that the horse was positioned on its side, making it difficult to perform the surgery. Silber was confident that if the horse could be placed on its back, the procedure would be a success. Laying an anesthetized horse on its back for a prolonged period of time can be challenging due to their size and physiology. Veterinarians decided it could be done, but only if the surgery time was kept to a minimum. In October 2007, the team operated on Minnesota again—completing the procedure in an hour. Six months later, the Zoo’s veterinarians and reproductive scientists collected a semen sample from the horse that indicated the procedure had been a success.

“I’ve always dreamed of using my expertise to contribute in some way to wildlife survival,” said Dr. Silber. “It also was exciting to pioneer a new procedure for which humans were the ‘test animal.” National Zoo scientists hope to pair Minnesota with a suitable female later in the coming months. His genes will infuse genetic diversity in a Przewalski’s horse population that is based on genes from only l4 original animals. National Zoo scientists are researching ways to improve fertility and produce more offspring in the aging, captive population. Bolstering the population translates into more horses for future reintroduction programs, essential for a critically endangered species. Currently, National Zoo scientists are working in remote areas of China using radio collars and Geographic Information System technology to map the movements of Przewalski’s horses reintroduced by Chinese colleagues into their former habitat. This breakthrough also has important implications for how endangered species in captivity are managed. The new knowledge could allow males and females of a species to be exhibited together but temporarily prevented from producing offspring if the Species Survival Plan—a cooperative breeding program among zoos—does not recommend them for breeding.

Science Daily
July 8, 2008

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Technique used in human ankle injuries modified to treat dogs’ knees

A common sports injury in human knees is even more common in dogs. Each year, more than one million dogs suffer from cranial cruciate ligament (CCL) deficiency, which is comparable to the anterior cruciate ligament (ACL) injury in humans. The common method of treatment by many veterinary surgeons involves cutting the tibia bone to stabilize the CCL-deficient knee in these dogs. Now, a new minimally invasive technique with less severe complications than previous methods has been developed by a University of Missouri College of Veterinary Medicine researcher. Unlike humans, CCL injuries in dogs typically do not occur because of a single trauma to the knee but are the result of a degenerative process that leads to early and progressive arthritis. For this reason, and the unique biomechanics of the canine knee, techniques used to repair the injury in humans do not work well for dogs. The new technique, known as Tightrope CCL, is modified from a technique used in human ankles and allows placement of a device that stabilizes the CCL-deficient knee through bone tunnels drilled using very small incisions. MU veterinarian James Cook worked with Arthrex Inc. from Naples, Fla., to develop and test the Tightrope device for dogs.

“Other current techniques require major surgery that involve cutting the bone, which can potentially lead to severe complications, such as fracture, implant failure and damage to the joint,” said Cook, professor of veterinary medicine and surgery and the William C. Allen Endowed Professor for Orthopedic Research. “This new technique is minimally invasive, relatively easy to perform and cost effective compared to other techniques. The dogs in the preliminary trial study experienced fewer and less severe complications with outcomes that were equal to or better than those seen with the bone-cutting technique.” Cruciate ligament tears are five times more common in dogs than humans and cost U.S. pet-owners more than $1.3 billion each year. The new technique is not for every dog. Because surgeons must be able to drill tunnels in the bone, dogs must weigh at least 40 pounds for the Tightrope CCL method to be feasible. In addition, dogs that cannot follow a physical rehabilitation protocol after surgery and dogs with limb deformities are not candidates for this technique. The 10- to 12-week rehabilitation period is very important for any surgical technique for CCL deficiency in order to optimize successful return to pain-free function and reduce complications, Cook said. “The times the Tightrope CCL technique has failed are when owners did not give their dogs the full rehabilitation period and let their dogs run, play or traumatize the joint before the knees were ready,” Cook said. “A successful operation is dependent on postoperative care so that the dog can heal well and build muscle for long term function. The Tightrope CCL technique is designed to allow this to happen with less surgery and less risk of a major problem arising, and so far, it has been successful.”

Science Daily
July 8, 2008

Original web page at Science Daily

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Modified surgical technique further reduces lung surgery pain

A simple variation in a surgical technique developed at the University of Alabama at Birmingham (UAB) to reduce acute and chronic pain following lung surgery further reduces pain and helps return patients to normal activity quicker than the previous technique, according to a study published in the June issue of the Annals of Thoracic Surgery. Instead of crushing the intercostal muscle and nerve that lies between the ribs during rib spreading when performing a lung resection, UAB Chief of Thoracic Surgery Robert J. Cerfolio, M.D., teases the muscle and nerve away from the rib and then moves it out of the way before spreading the ribs. This leads to less trauma to the muscle and intercostal nerve and dramatically reduces post-operative pain. This new technique is a further modification of a concept that Cerfolio and colleagues reported in 2005. As reported in that paper, the technique divided, then moved, the intercostal muscle and the nerve away from the rib spreader so it was not crushed. In this new modification, the muscle is no longer divided but is allowed to dangle under the rib spreader, further avoiding trauma to the nerve and muscle.

For the 160 patients participating in this study, those who received the modified muscle flap technique reported that pain was reduced both in the hospital and after surgery at weeks three, four, eight and 12. Those who received the modified muscle flap procedure had lower pain scores and required less pain medications than those who did not. They also were more likely to return to normal activities within eight to 12 weeks after the surgery. The study used sophisticated, objective measurements of pain, including multiple pain score surveys, and measurements of patients’ pain medication usage. The original idea for the Cerfolio technique was generated from an earlier study Cerfolio published in the Annals of Thoracic Surgery in 2004. “In the first study, we found a way to avoid injury to the intercostal nerve that lies below the sixth rib during closure by drilling holes in the ribs so the closure stitches would not entrap that nerve,” Cerfolio said. “Then, I got the idea that maybe we could further reduce the pain by avoiding the intercostal nerve and muscle that lie above the sixth rib during opening and came up with the idea of harvesting the intercostal muscle flap prior to chest retraction. As surgeons, we are constantly looking for ways to improve techniques and reduce pain.” To date, a number of surgeons and other clinical staff from all over the world, including, Denmark, The Netherlands, Germany, France and Spain have recently come to UAB to observe Cerfolio perform lung surgery and learn this new technique. Cerfolio is recognized as one of the busiest thoracic surgeons in the world and performs more than 1,200 surgeries each year.

Science Daily
June 24, 2008

Original web page at Science Daily

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Surgeon operates to rescue chimp with rare deformity

An orthopaedic surgeon at the University of Liverpool has performed a groundbreaking operation on a chimp in Cameroon to correct a deformity more commonly seen in dogs. The three year-old chimp called Janet was rescued from the Cameroon pet trade last year and now lives in a chimpanzee reserve supported by the Cameroon Wildlife Aid Fund. Janet was unable to climb and had difficulty walking because a bone in her forearm – the ulna – had stopped growing. It is thought that her condition, known as angular limb deformity, is a congenital problem, but could also have been caused or aggravated by being chained at the wrist by traders. This forced the arm’s radius to grow in a circular manner making her arm severely bent. Vets have seen the deformity in dogs before but never in chimpanzees and were called in to assess Janet’s condition.

Rob Pettitt, orthopaedic surgeon at the University’s Small Animal Teaching Hospital, said: “Surgery to correct the condition in dogs is less complex than the procedure in chimps. In dogs bone tissue stops growing early in life, so once the limb is straightened there is little time for the deformity to recur and interfere with bone development. In chimps and humans however, the areas of growth at the end of long bones can stay open for years, so there is plenty of time for the condition to return. We therefore sought the advice of specialists at Robert Jones and Agnes Hunt orthopaedic hospital at Oswestry – to make sure we protected any growth left in Janet’s limb. “The first step was to remove the far end of the ulna, which had become compacted due to the continued growth of the radius. A 14mm triangular section of bone was then removed from the radius in order to straighten the limb and a bone plate was inserted into the radius to secure the two ends of the bone.”

Selling chimps as pets is illegal but rife on the black market in Cameroon. Adult chimpanzees are slaughtered for their meat and the young chimps are then taken away and sold as pets. Rachel Hogan, manager of the chimpanzee reserve in Cameroon, said: “Janet is recovering well and has now rejoined her group at the reserve. She has been undergoing physiotherapy so that she can learn how to use the limb properly. She is made to grip a ball a few times a day and undo bottle tops to exercise her wrist. The X-rays show the surgery was a complete success.”

Science Daily
May 27, 2008

Original web page at Science Daily

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New surgery improves head and neck cancer treatment

A new surgical procedure for head and neck cancer at the University of Alabama at Birmingham offers improved accuracy for surgeons and reduced post-operative pain for patients. Initial tests have shown the new procedure also shortens recovery times for cancer patients. “This application takes robotic surgery to new places in the body,” said Carroll, a head and neck surgeon within UAB’s Division of Otolaryngology, and one of the first surgeons to begin using the procedure for head and neck cancers. “There is an option for patients to have a more minimally invasive surgery, and one that could effectively remove the cancer while causing fewer side effects,” he said.

Robotic surgery is an alternative to traditional open surgery and a refinement on the concept of laparoscopic surgery, Carroll said. The robot most commonly used in cancer treatment is called the da Vinci, which is sold by Intuitive Surgical. UAB was the first medical center in Alabama and among the first in the United States to begin using the da Vinci for head and neck cancers more than a year ago. Since that time, 40 UAB patients have had the new operation. Offering the new procedure to patients first involved adapting operating techniques and robot-arm positions, and continually refining those adaptations, Carroll said. The da Vinci was originally designed for operating on the lower and middle sections of the body, and the narrow spaces inside the head and neck can be a challenge. The increased surgical accuracy comes from tiny cameras attached to the end of the da Vinci instruments. Carroll said the magnified, 3-D image gives doctors a greater field of vision than conventional open or laparoscopic surgery.

Science Daily
May 13, 2008

Original web page at Science Daily

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Long-term benefit of carotid stenting as alternative to surgery

Carotid artery stenting is an effective option for high risk patients who are not eligible for surgery, according to a long-term study published in this week’s New England Journal of Medicine. Carotid artery disease, which involves clogging of the arteries in the neck that provide blood to the brain, is a significant risk factor for stroke, making these study results important for the estimated 200,000 Americans each year who would otherwise not be candidates for the treatment. The SAPPHIRE trial showed patients undergoing carotid stenting were comparably protected from stroke, heart attack, death, and repeat revascularization procedures as patients who underwent the traditional surgical approach (endarterectomy). SAPPHIRE is the first and longest (three years) randomized study to compare the safety and efficacy of carotid stenting with embolic protection to surgery in high risk patients. High risk patients are considered to be at increased risk for surgery because of prior carotid artery surgery, radiation to the neck, chronic heart failure, lung disease or severe coronary artery disease, among other criteria.

The Society for Cardiovascular Angiography and Interventions (SCAI), the world’s leading society of interventional cardiologists, is encouraged by these positive data. Results are consistent with one-year SAPPHIRE data and echo conclusions from other non-randomized trials supporting the use of carotid stenting, particularly in patients with multiple illnesses. “This is more good news for patients who otherwise might not have treatment options,” said Dr. Bonnie Weiner, president of the Society for Cardiovascular Angiography and Interventions. “Carotid artery stenting is an effective, safe way to help patients avoid debilitating and potentially fatal strokes. We are hopeful that this news will help pave the way for expanded use of this procedure.” Carotid artery stenting is a non-surgical, percutaneous procedure in which a small plastic tube called a catheter is inserted through an artery in the leg and threaded to the blockage in the neck. A thin wire (guidewire), which has a collapsible umbrella-like filter device attached to its end, is advanced passed the blockage. The umbrella is opened and acts as a filter to the blood flowing to the brain, preventing particles from passing to the brain and causing stroke while opening up the blockage and inserting a tiny mesh tube called a stent. The blocked artery is then dilated by inflating a balloon, which pushes the plaque in the artery against its walls and makes way for the stent, which is inserted to prop open the artery. Once the stent is in place, the umbrella filter is removed.

Science Daily
April 29, 2008

Original web page at Science Daily

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Surgeons announce advance in atrial fibrillation surgery

Heart surgeons at Washington University School of Medicine in St. Louis report that by adding a simple 10-20 second step to an operative procedure they achieved a significant improvement in the outcome for the surgical treatment of atrial fibrillation (AF). Reporting in the April issue of the Journal of Thoracic and Cardiovascular Surgery, the surgeons describe an enhancement to the Cox-Maze procedure, a surgical procedure that redirects wayward electrical impulses causing AF by creating precisely placed scars, or ablations, in the heart muscle. The Cox-Maze procedure is highly effective, offering the best long-term cure rate for persistent atrial fibrillation. The surgeons added one ablation to the series of ablations typically made during the Cox-Maze procedure and that short step improved how well patients did after surgery. As a result, they recommend using this extra ablation in all patients undergoing the procedure. “The single additional ablation creates what we call a box lesion,” explains Ralph J. Damiano Jr., M.D., the John Shoenberg Professor of Surgery at the School of Medicine. “The box lesion surrounds and electrically isolates the pulmonary veins and the posterior left atrial wall from the rest of the left atrium. Our study shows excellent success when using the box lesion, and we recommend it for any patient with long-standing atrial fibrillation.”

AF is the most common irregular heart rhythm and affects more than 2 million people in the United States. During atrial fibrillation, the upper chambers (atria) of the heart beat rapidly and quiver instead of contracting, drastically reducing the amount of blood they pump. AF can cause fatigue, shortness of breath, exercise intolerance, heart palpitations and stroke. The area of the heart near the pulmonary veins is a common source of the irregular electrical impulses that can cause AF. Without the box lesion, in some patients this area could still support electrical signals that disrupt the regular contractions of the heart’s upper chambers. Led by Damiano, also chief of cardiac surgery at the School of Medicine and a cardiac surgeon at Barnes-Jewish Hospital, the Washington University surgeons revolutionized AF treatment in 2002 by helping develop a radiofrequency clamp that creates the ablation lines needed to reroute electrical impulses in the heart. The clamp directs radiofrequency energy into the heart muscle and creates a full-thickness scar.

The radiofrequency clamp procedure is quicker and easier than the original “cut and sew” Cox-Maze procedure, which was developed by James Cox, M.D., at Washington University in 1987. The original procedure relied on a complex series of 10 incisions in the heart muscle, creating a “maze” to channel errant electrical impulses where they should go. In the newer version, called Cox-Maze IV, most of these incisions were replaced by radiofrequency ablations, reducing the operation from an average of 90 minutes to about 30 minutes. The current study involved two groups of patients with AF. One group underwent radiofrequency ablation-assisted Cox-Maze IV procedures without a box lesion and the other with a box lesion. The box lesion group had a 48 percent lower occurrence of atrial flutter and fibrillation in the first weeks after surgery. These patients also had shorter hospital stays (nine days on average) than patients who had the standard Cox-Maze IV procedure (average stay of 11 days).

Three months after surgery, 95 percent of patients who had the box lesion had no signs of AF, while only 85 percent of the patients who had the standard Cox-Maze IV procedure were free from AF. By six and 12 months postsurgery, all of the patients in the box lesion group were free from AF compared to 90 percent of the other group, although that difference was not statistically significant. “We also saw that the use of antiarrhythmic drugs was lower after three and six months in those who received a box lesion,” Damiano says. “These drugs can have serious side effects, and if patients can stop using them they often feel better. Overall, the use of the box lesion set was associated with shorter hospitalization, fewer medications and reduced recurrence of atrial fibrillation. We were very pleased with these results.” Compared to those without atrial fibrillation, people 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 usually do not cure the disorder.

Science Daily
April 29, 2008

Original web page at Science Daily

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Bones mend faster without marrow

A new study in rats suggests that the technique could kick-start rapid self-healing in weakened or fractured bones, if followed up with injections of a bone growth hormone. Agnes Vignery’s team at Yale University anaesthetised a group of rats and drilled into the left thigh-bone of each animal before syringing out the bone marrow. Some of the rats received daily doses of parathyroid hormone (PTH), a clinically approved drug that encourages the growth of new bone. After two weeks, X-rays of the rats showed that new bone had begun to form in the bone marrow cavity. In most rats, the new bone was short-lived – by the third week, marrow began to reappear and any new bone cells were reabsorbed to make room. But in the rats treated with PTH, new bone continued to grow in the cavity into the third week and the marrow did not return. Vignery’s team also discovered that the de-marrowed thighbones of the PTH-treated rats were stronger than their other legs, and the legs of rats not given PTH (Tissue Engineering, DOI: 10.1089/ten.2007.0261). The study suggests that bone marrow usually inhibits the formation of new bone, says Vignery, and that simply removing the marrow and using drugs to encourage new bone growth could help treat weakened or broken bones.

“At first glance this appears counter-intuitive,” says Brendon Noble at the University of Edinburgh, UK, since bone marrow generates the stem cells that would usually help repair bones. However, periosteum cells in the membrane that lines the outside of bones also have regenerative powers. “Perhaps they are sufficient to take on the role,” Noble says. Bone marrow is also needed to produce new blood cells, but Vignery says that removing it from damaged bones shouldn’t affect a person’s health, so long as marrow remains in other bones. Warren Levy of Unigene Laboratories, in Fairfield, New Jersey, which provided Vignery’s team with PTH for the study, believes the procedure could radically change the way patients are treated, particularly those with hip fractures. Such fractures often require major surgery, which is expensive and can be life-threatening in elderly patients. “Instead, if an X-ray reveals a fracture, you could go in with a needle right there in the doctor’s suite and do without surgery,” Levy says. The patient would then be sent home with a prescription for PTH, and new bone would grow in the marrow cavity, repairing the fracture from the inside. Peter Kay of the University of Manchester, UK, agrees that the technique sounds promising. “This sort of minimally invasive technique to replace surgery sounds controversial, but if you can strengthen rat’s bones maybe there is potential.” Levy says further animal tests are needed, but they hope to test the technique in humans before the end of the year.

Eurekalert! Medicine
April 15, 2008

Original web page at Eurekalert! Medicine

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Diabetes may be disorder of upper intestine: Surgery may correct it

Growing evidence shows that surgery may effectively cure Type 2 diabetes — an approach that not only may change the way the disease is treated, but that introduces a new way of thinking about diabetes. A new article — published in a special supplement to the February issue of Diabetes Care by a leading expert in the emerging field of diabetes surgery — points to the small bowel as the possible site of critical mechanisms for the development of diabetes. The study’s author, Dr. Francesco Rubino of NewYork-Presbyterian Hospital/Weill Cornell Medical Center, presents scientific evidence on the mechanisms of diabetes control after surgery. Clinical studies have shown that procedures that simply restrict the stomach’s size (i.e., gastric banding) improve diabetes only by inducing massive weight loss. By studying diabetes in animals, Dr. Rubino was the first to provide scientific evidence that gastrointestinal bypass operations involving rerouting the gastrointestinal tract (i.e., gastric bypass) can cause diabetes remission independently of any weight loss, and even in subjects that are not obese.

“By answering the question of how diabetes surgery works, we may be answering the question of how diabetes itself works,” says Dr. Rubino, who is a professor in the Department of Surgery at Weill Cornell Medical College and chief of gastrointestinal metabolic surgery at NewYork-Presbyterian/Weill Cornell. Dr. Rubino’s prior research has shown that the primary mechanisms by which gastrointestinal bypass procedures control diabetes specifically rely on the bypass of the upper small intestine — the duodenum and jejunum. This is a key finding that may point to the origins of diabetes. “When we bypass the duodenum and jejunum, we are bypassing what may be the source of the problem,” says Dr. Rubino, who is heading up NewYork-Presbyterian/Weill Cornell’s Diabetes Surgery Center. In fact, it has become increasingly evident that the gastrointestinal tract plays an important role in energy regulation, and that many gut hormones are involved in the regulation of sugar metabolism. “It should not surprise anyone that surgically altering the bowel’s anatomy affects the mechanisms that regulate blood sugar levels, eventually influencing diabetes,” Dr. Rubino says.

While other gastrointestinal operations may cure diabetes as an effect of changes that improve blood sugar levels, Dr. Rubino’s research findings in animals show that procedures based on a bypass of the upper intestine may work instead by reversing abnormalities of blood glucose regulation. In fact, bypass of the upper small intestine does not improve the ability of the body to regulate blood sugar levels. “When performed in subjects who are not diabetic, the bypass of the upper intestine may even impair the mechanisms that regulate blood levels of glucose,” says Dr. Rubino. In striking contrast, when nutrients’ passage is diverted from the upper intestine of diabetic patients, diabetes resolves. This, he explains, implies that the upper intestine of diabetic patients may be the site where an abnormal signal is produced, causing, or at least favoring, the development of the disease. How exactly the upper intestine is dysfunctional remains to be seen. Dr. Rubino proposes an original explanation known in the scientific community as the “anti-incretin theory.”

Incretins are gastrointestinal hormones, produced in response to the transit of nutrients, that boost insulin production. Because an excess of insulin can determine hypoglycemia (extremely low levels of blood sugar) — a life-threatening condition — Dr. Rubino speculates that the body has a counter-regulatory mechanism (or “anti-incretin” mechanism), activated by the same passage of nutrients through the upper intestine. The latter mechanism would act to decrease both the secretion and the action of insulin. “In healthy patients, a correct balance between incretin and anti-incretin factors maintains normal excursions of sugar levels in the bloodstream,” he explains. “In some individuals, the duodenum and jejunum may be producing too much of this anti-incretin, thereby reducing insulin secretion and blocking the action of insulin, ultimately resulting in Type 2 diabetes.” Indeed, in Type 2 diabetes, cells are resistant to the action of insulin (“insulin resistance”), while the pancreas is unable to produce enough insulin to overcome the resistance.

After gastrointestinal bypass procedures, the exclusion of the upper small intestine from the transit of nutrients may offset the abnormal production of anti-incretin, thereby resulting in remission of diabetes. In order to better understand these mechanisms, and help make the potential benefits of diabetes surgery more widely available, Dr. Rubino calls for prioritizing research in diabetes surgery. “Further research on the exact molecular mechanisms of diabetes, surgical control of diabetes and the role played by the bowel in the disease may bring us closer to the cause of diabetes.” Today, most patients with diabetes are not offered a surgical option, and bariatric surgery is recommended only for those with severe obesity (a body mass index, or BMI, of greater than 35kg). “It has become clear, however, that BMI cut-offs can no longer be used to determine who is an ideal candidate for surgical treatment of diabetes,” says Dr. Rubino. “There is, in fact, growing evidence that diabetes surgery can be effective even for patients who are only slightly obese or just overweight. Clinical trials in this field are therefore a priority as they allow us to compare diabetes surgery to other treatment options in the attempt to understand when the benefits of surgery outweigh its risks. Clinical guidelines for diabetes surgery will certainly be different from those for bariatric surgery, and should not be based only on BMI levels,” he notes.

“The lesson we have learned with diabetes surgery is that diabetes is not always a chronic and relentless disease, where the only possible treatment goal is just the control of hyperglycemia and minimization of the risk of complications. Gastrointestinal surgery offers the possibility of complete disease remission. This is a major shift in the way we consider treatment goals for diabetes. It is unprecedented in the history of the disease,” adds Dr. Rubino. Type 2 diabetes, which accounts for 90 to 95 percent of all cases of diabetes, is a growing epidemic that afflicts more than 200 million people worldwide. At a time when diabetes is growing epidemically worldwide, Dr. Rubino says that finding new treatment strategies is a race against time. “At this point, missing the opportunity that surgery offers is not an option.” In addition to having performed landmark studies in the field of diabetes surgery, Dr. Rubino was the principal organizer of an influential Diabetes Surgery Summit, held in Rome in March 2007. This international consensus conference helped establish the field, making international recommendations for the use of surgery and creating an International Diabetes Surgery Task Force. Dr. Rubino serves as a founding member.

Science Daily
March 17, 2008

Original web page at Science Daily

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Polluted prey causes wild birds to change their tune

Considerable attention has been paid to the effects of endocrine disrupting chemicals in aquatic environments, but rather less attention has been given to routes of contamination on land. A new study by researchers at Cardiff University, reveals that wild birds foraging on invertebrates contaminated with environmental pollutants, show marked changes in both brain and behaviour: male birds exposed to this pollution develop more complex songs, which are actually preferred by the females, even though these same males usually show reduced immune function compared to controls. Catherine Buchanan and her colleagues studied male European starlings (Sturnus vulgaris) foraging at a sewage treatment works in the south-west UK and analysed the earthworms that constitute their prey. The researchers found that those birds exposed to environmentally-relevant levels of synthetic and natural estrogen mimics developed longer and more complex songs compared to males in a control group.

Specifically, birds dosed with the complete spectrum of endocrine disrupting chemicals found in the invertebrates spent longer singing, sang more often and produced more complex songs, a sexually selected trait important in attracting females for reproduction even though birds dosed at these ecologically relevant levels also showed reduced immune function. The study also addresses the mechanism for this effect, as the researchers found that the high vocal centre (HVC), the area of the brain that controls male song complexity, is significantly enlarged in the contaminated birds. Estrogen causes masculinisation of the songbird brain and the HVC is enriched with estrogen receptors. Neural development is thus susceptible to exposure to chemicals which mimic estrogen, or to enhanced estrogen levels. The results also confirm the plasticity of the adult songbird brain. Finally, the scientists found that female starlings prefer the song of males exposed to the mixture of endocrine disrupting chemicals, suggesting the potential for population level effects on reproductive success.

Science Daily
March 17, 2008

Original web page at Science Daily

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Cyst removed from baby gorilla by medical surgeons

A surgical team of two neurosurgeons and a neonatologist from Seattle’s Children’s Hospital and Regional Medical Center of Seattle joined Woodland Park Zoo’s Animal Health staff yesterday to perform surgery on a two-and-a-half-month-old, female western lowland gorilla. The specialized medical team was mobilized to remove a growth overlying the spine of the 9-pound gorilla. The surgery was performed at the zoo’s state-of-the-art veterinary hospital using a state-of-the-art neuro spinal instrument set donated by New Jersey-based Integra LifeSciences Corporation (NASDAQ: IART). The surgery followed a consultation and MRI diagnostics, donated last month by Dr. Rob Liddell of Radiology Consultants of Washington. The mass and MRI diagnostics closely resemble a congenital condition found in human infants. “This gorilla operation was an amazing ‘Star Trek’-type of experience for the team from Children’s Hospital and University of Washington,” said Dr. Richard Ellenbogen, neurosurgeon from Children’s Hospital and Regional Medical Center. “Drs. Craig Jackson, Sam Browd, and I were proud to help with an endangered species such as the baby gorilla suffering from a congenital spinal abnormality. The operation was a great success from our perspective, and we are hoping for a full recovery.”

“ Surgery confirmed that the mass extended down to the spine but did not invade the spinal column,” explained the zoo’s Interim Director of Animal Health Dr. Kelly Helmick. The cause of the mass is pending results of biopsy diagnostics. Following the one-hour procedure and recovery from anesthesia, the baby gorilla was returned to her mother at the gorilla exhibit. Staff will keep her under close observation and continue antibiotic treatment. “The successful outcome of the surgery is due, in large part, to our dedicated gorilla keepers, who successfully trained the mother to help us give her infant liquid antibiotics,” explained Helmick. “This important pre-surgical care helped stem the infection and inflammation and decrease the surgical time.” The surgery, MRI diagnostics, and consultation by an obstetrician were all donated to the zoo. “We are extremely grateful to the entire medical team for volunteering their time and specialized skills for our young conservation ambassador,” added Helmick.

The field of zoo and wildlife medicine is a rapidly evolving science. Detecting medical concerns and applying cutting-edge treatment, when possible, is a strategy for ensuring quality health care for the zoo’s collection of more than a thousand animals. In addition to our excellent team here of full-time veterinarians, veterinary technicians and hospital keepers, “we collaborate with a network of more than 70 ‘human’ medical doctors, consulting veterinarians, and health care professionals who donate their time and expertise to help us provide quality care for our animals,” explained Helmick. “As an accredited member of the Association of Zoos & Aquariums (AZA), we are committed to providing the best possible veterinary care to each and every animal at the zoo.” The zoo currently houses 12 gorillas in two separate groups in the award-winning Tropical Rain Forest. The infant gorilla, which remains unnamed, was born October 20 at Woodland Park Zoo. She represents the twelfth successful gorilla birth for the zoo and the third offspring between 38-year-old Amanda and the father, 29-year-old Vip. According to Martin Ramirez, a curator at Woodland Park, the mother continues to show excellent maternal care. “Amanda is a very attentive mother. She and her infant continue to bond appropriately.” The zoo plans on inviting the community later this spring to help name the baby gorilla.

Science Daily
January 22, 2008

Original web page at Science Daily

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Fetal surgeon shows for first time that laser procedure may treat vasa previa

A University of South Florida fetal surgeon at Tampa General Hospital successfully treated in utero a rare but potentially devastating condition in which placental blood vessels block the birth canal and can rupture during labor, leaving the baby without vital blood and oxygen. If undiagnosed, the condition known as vasa previa is frequently deadly for newborns. The case was reported by Ruben Quintero, MD, professor and director of the Division of Maternal-Fetal Medicine at USF Health, in the December 2007 issue of the Journal of Maternal-Fetal and Neonatal Medicine. Dr. Quintero used a laser to seal off the abnormally positioned fetal blood vessels connecting the two parts of a bilobed placenta. The procedure essentially removed the unprotected vessels crossing the cervical entrance to the birth canal beneath the baby, so that the vessels would not tear or break and cause rapid fetal hemorrhage.

“This is the first time laser therapy has been used to correct vasa previa,” said Dr. Quintero, a pioneer in the field of minimally-invasive fetal surgery. “Patients have described this prenatal condition as a ticking time bomb waiting to go off. A patient with vasa previa lives with the constant worry that if her water breaks at any time, she may lose the pregnancy.” “Dr. Quintero has long been recognized for his excellence in innovation in fetal intervention. His successful in utero laser treatment of vasa previa is potentially a very important breakthrough because it may avert fetal hemorrhage,” said Frank Chervenak, MD, chairman of the Department of Obstetrics and Gynecology, NewYork-Presbyterian Hospital/Weill Cornell Medical Center. “This report must be followed by scientifically and ethically rigorous clinical investigation before being offered to patients as the standard of care.” Dr. Quintero is an expert at pinpointing abnormal placental vessels with an endoscope inserted through the abdominal wall and into the uterus. Using a selective endoscopic technique he developed, he had already performed hundreds of laser ablations of malfunctioning placental blood vessels to treat twin-to-twin transfusion syndrome. Vasa previa occurs in about 1 in every 2,000 to 5,000 pregnancies. Despite advances in medical technology, the condition often goes undetected until it is too late and then an emergency caesarian section and aggressive resuscitation is required to save the baby. Vasa previa has a high death rate if it’s not caught before labor, because many babies lose most or all of their blood supply within a few minutes when their mother’s water breaks. A color Doppler ultrasound showing blood flow in the womb can help detect vasa previa, but unless a woman is identified as having a high-risk pregnancy, she typically does not get this more sophisticated test during pregnancy.

The 37-year-old patient described in the published report had an abnormal placenta with one smaller and one larger lobe linked by two exposed fetal vessels. Normally the blood vessels feeding the fetus are embedded in the placenta or umbilical cord, but in this case the vessels linked the two lobes. This would not necessarily be life-threatening if the unsupported vessels were positioned in other areas of the uterus — but these vessels were caught between the fetus and the opening to the birth canal (cervix). Such exposed vessels are prone to tearing when the patient’s amniotic membranes rupture, or they may be compressed between the baby and the walls of the birth canal during birth, cutting off oxygen to the baby. There is no uniform standard of care for vasa previa. When the condition is diagnosed, physicians often manage it by recommending bed rest, hospitalizing the patient beginning at 7 months of pregnancy and scheduling an elective cesarean delivery before labor. However, Dr. Quintero suggests, the risk of fetal death might be substantially minimized if the unprotected vessels were ablated in utero. Laser treatment might eliminate prolonged hospitalization and the obligatory C-section, and allow the pregnancy to progress to term with a vaginal delivery, he said.

The patient described in Dr. Quintero’s paper was counseled about management alternatives and elected to undergo laser surgery to seal the abnormal fetal vessels. The procedure was performed at Tampa General Hospital at about 23 weeks of pregnancy without complications, Dr. Quintero reported. However, the patient subsequently required a cesarean delivery at 27 weeks for ruptured membranes, which may have been prompted by the breech position of the fetus. After a stay in the neonatal intensive care unit, the infant was discharged and is thriving today at 9 months old. “This case is a first step requiring more study to determine the effectiveness of the procedure and its risks,” Dr. Quintero said. “But it demonstrates that, if an accurate diagnosis is made, something proactive may be done to treat vasa previa.

Science Daily
January 22, 2008

Original web page at Science Daily

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Knee operations can lead to other injuries

Operating on an anterior cruciate ligament injury can lead to other damage to the knee and to changes that remain a full year after the first injury. If an operation is to be carried out, the patient may have to rest his/her knee longer than would have been necessary without an operation. “If operated young soccer players return to play after just a few months, the risk of osteoarthritis development in the knee will increase in the long term” says researcher Richard Frobell. He addresses ACL injuries in a new thesis from Lund University in Sweden. Richard Frobell studied cruciate ligament injuries with a magnetic resonance camera (MR), a technique that is not usually applied in these contexts. The camera images show that the ligament injury in the knee joint as such is only part of the problem. Most of the patients also had, besides meniscus injuries, fractures and bone marrow lesions, that is, damage to the porous bone and bleeding in the bone marrow.

“This is new to the research society. A common belief is to treat these injuries as largely affecting the cruciate ligament only, something that could be reconstructed using a muscle tendon, and the patient would be fine,” says Richard Frobell. But operating can in fact make the knee worse. The MR study shows that knees that were operated on evinced still swollen joints, bone marrow damage, and cartilage changes one year after the original injury more often than knees that had not been operated on. “Some athletes return very early to sports despite the fact that they have these types of complaints. Returning to sports early is often considered as a sign of a successful operation. But the risk of these people developing osteoarthritis in the future may have increased,” says Richard Frobell. Arthritis researchers have long been aware of the link between knee injuries and arthritis. The fact that injured players nevertheless go back to soccer is due to the fact that arthritis research has not been able to make an impact on sports medicine: to some extent they inhabit two separate medical worlds.

Richard Frobell also claims that knees with damaged anterior cruciate ligaments should not be operated on in early stages. “Unless there is clear evidence that an operation is necessary, it’s better to wait and see what structured rehabilitation can achieve. This is what we usually do in southern Sweden, with good results. Elsewhere there seems to be an exaggerated believe in surgical treatment, but this believe is not based on science,” he says. The dissertation also shows that as many as every second anterior cruciate ligament injury remains undetected. MR technology, which can help reveal undiagnosed injuries, is not commonly used by emergency wards at orthopedic clinics, and the damage is not shown in a regular x-ray. “If the right questions are not asked, the swollen knee is not detected, and if the knee is not aspirated to verify bleeding in the joint, these patients will all too often be dismissed as having a simple knee sprain,” says Richard Frobell. He feels that every patient with a possible cruciate ligament injury should be referred to an experienced diagnostician, so that injuries will not be missed and grow worse.

Science Daily
January 8, 2008

Original web page at Science Daily

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New mechanical insights into wound healing and scar tissue formation

New research illuminates the mechanical factors that play a critical role in the differentiation and function of fibroblasts, connective tissue cells that play a role in wound healing and scar tissue formation. When we are injured, the body launches a complex rescue operation. Specialized cells called fibroblasts lurking just beneath the surface of the skin jump into action, enter the provisional wound matrix (the clot) and start secreting collagen to close the wound as fast as possible. This matrix is initially soft and loaded with growth factors. The fibroblasts “crawl” around the matrix, pulling and reorganizing the fibers. The matrix grows stiffer, and at a certain point, the fibroblasts stop migrating and, like Popeye, change into powerful contractile cells, anchoring themselves to the matrix and pulling the edges of the wound together.

This research reveals for the first time that a mechanical mechanism is crucial for this switch from migrating to contractile cells. To make this change, the fibroblasts need to get at their “spinach” — the growth factor sitting in the matrix which, once liberated, stimulates the production of smooth-muscle proteins. Previously, researchers postulated that the fibroblasts did this by digesting the matrix. But EPFL scientist Boris Hinz, doctoral student Pierre-Jean Wipff and their colleagues have discovered that the cells unlock the growth factor via a purely mechanical process. With experiments using novel cell culture substrates of varying rigidity, they found that at a certain point, the matrix is sufficiently rigid that cell-exerted force allows the growth factor to pop out, like candy from a wrapper. Once the growth factor is available, the fibroblast expresses the contractile proteins, sticks more firmly to the matrix and starts to contract, pulling the matrix tightly together. In the process it liberates yet more growth factor that in turn stimulates other fibroblasts to become contractile. The mechanical nature of the switch ensures that the contraction only develops when the matrix is “ready.”

Although this process will heal a wound quickly, if left unchecked, it can also lead to a buildup of fibrous tissue. Following trauma to vital organs such as the heart, lung, liver and kidney, overzealous fibroblasts can continue to build fibrous strands, leading to scar tissue buildup that can impair the organ’s function. This condition, called “fibrosis”, can be fatal. Fibroblasts are also the culprits in problems caused by implants — if the implant is too smooth, it never becomes properly incorporated into the connective tissue. But if it is too rough, scar tissue develops around it and it won’t function properly. Occasionally, following plastic surgery, unsightly excessive scar tissue can develop in the skin as well. The process can also cause problems in mesenchymal stem cell cultures — if the culture’s substrate is stiff, considerable efforts have to be made to prevent the stem cells from turning prematurely into fibroblasts instead of the desired cell type. Controlling the rigidity of the cell culture is therefore critical.

This new understanding of the mechanical nature of fibroblast activation could be used to reduce or prevent fibrosis from occurring, says Hinz, without inhibiting the growth factor, which serves many other vital functions in the body. There are several possibilities: “You could interfere with the way the cells grab onto the growth factor complex, you could interfere with their attachment points on the matrix, and you could interfere with their contractile forces so that the matrix never gets stiff enough to liberate the growth factor,” he suggests.

Science Daily
January 8, 2008

Original web page at Science Daily

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Cryoablation continues to show good results for kidney cancer patients

A review of 62 Mayo Clinic patients who underwent cryoablation to treat cancerous kidney tumors shows that the patients are cancer free for up to two and a half years after having had the procedure. Also called cryotherapy or cryosurgery, cryoablation is a procedure in which extreme cold is applied to the tumor using a cryoprobe, a hollow needle-like device filled with argon gas. The gas rapidly freezes the targeted tumor. As this study and others continue to show, cryoablation appears to be an effective treatment for cancerous kidney tumors. But researchers caution that at this time, it be used only for patients who are not candidates for surgery, because follow-up studies are needed before the procedure can be widely applied, states Thomas Atwell, M.D., a Mayo Clinic radiologist and the study’s primary investigator. “This procedure appears to be a good option for some patients,” he says. The general criteria for cryoablation includes the size and appearance of the tumor and the number of lesions in the kidney.

In this study, 89 of 91 tumors were effectively treated in a single treatment session. Patients had tumors that ranged in size from 1.5 centimeters (cm) to 7.3 cm. The average size was 3.4 cm. Follow-up evaluations ranging from three months to two and a half years were available for 62 patients — all whom remain cancer free at last report. The standard treatment for kidney tumors is surgery, which is highly effective. For patients who undergo surgery, the hospital stay and recovery period are longer as compared to patients treated with cryoablation. Patients who undergo cryoablation will have a small incision where the cryoprobe is inserted. The mark is covered with a bandage and recovery usually amounts to one day in hospital, as compared to several days for patients who undergo surgery.

Mayo Clinic
December 11, 2007

Original web page at Mayo Clinic

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Engineers developing new cements to heal spinal fractures

New research could offer hope for victims of the most devastating spinal injuries – typically those caused in car crashes. Biological cements to repair ‘burst fractures’ of the spine are being developed and tested in a major new collaborative project between the University of Leeds and Queen’s University Belfast. The team will be working to develop and examine the effects of novel cement materials for the treatment of burst fractures. Bone cements, similar to those used in joint replacement surgery, are already being used to strengthen damaged vertebrae of patients with diseases such as osteoporosis, in a procedure known as vertebroplasty, but ‘burst fractures’ to the spine, injuries often sustained in major impact accidents and falls, are much more difficult to treat. They account for over 1,000 emergency NHS admissions each year and often require highly complex, invasive surgery and a long stay in hospital.

“This type of fracture causes the vertebra to burst apart and in severe cases fragments of bone can be pushed into the spinal cord,” says Dr Ruth Wilcox of Leeds’ Institute of Medical and Biological Engineering. “Surgeons may be able to join bone fragments together and stabilize the spine with the use of metal screws and rods, but patients with these injuries are often in a really bad way, so the less invasive the treatment, the better.” The project team at Queen’s has expertise in developing and testing synthetic biomaterials for the repair of bone defects. “These materials can be delivered to the fracture site by injection and mimic the chemical composition of bone itself,” says Dr Fraser Buchanan, from the University’s School of Mechanical and Aerospace Engineering. At Leeds the team has expertise in computational modelling of the spine and will be able to provide Queen’s with data to assist in the development of novel biomaterials and to simulate how they will perform in patients. Statistically, burst fractures are seen more in younger people, and not enough is currently known about the long term consequences of using existing cements for the treatment of this type of injury. There is evidence to show that some patients with osteoporosis, who tend to be older, can develop fractures in the vertebrae adjacent to those treated with vertebroplasty.

“We think this may be because current cements are stiffer than the bone itself causing an imbalance in the way the spine bears weight. This may increase loading on the neighbouring vertebrae, which can lead to further damage” says Dr Wilcox. “Clearly we need to develop biomaterials that more closely match the properties of real bone. This project offers the perfect opportunity to use the range of complimentary skills of this grouping to predict the effects of newly developed cements and even incorporate biological agents to assist the body’s own healing process,” added Dr Buchanan. To be able to use bone cements for burst fractures would be a major leap forward. It would be simpler, quicker and much less invasive for the patient, reducing both recovery times and NHS costs.

Science Daily
November 12, 2007

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Stem cells in degenerating spinal discs discovered, potential for repair

Orthopedic researchers at Jefferson Medical College have for the first time found stem cells in the intervertebral discs of the human spine, suggesting that such cells might someday be used to help repair degenerating discs and remedy lower back and neck pain. Reporting November 1, 2007 in the journal Spine, a team led by Makarand Risbud, Ph.D., and Irving Shapiro, Ph.D., at Jefferson Medical College of Thomas Jefferson University in Philadelphia, have found stem cells in both degenerated adult human discs and in discs of animals. Many people suffer from lower back pain, and treatment ranges from painkillers such as acetominophen to medical procedures, such as fusing vertebrae. The combined annual costs for treatment of back pain and disc disease is approximately $100 billion a year and a major cause of lost work in the United States. According to Dr. Shapiro, as the discs in the spine degenerate, cells are lost and the ability to produce water-binding molecules called proteoglycans is decreased. The water absorbs forces on the spine, essentially serving as shock absorbers. Losing proteoglycans can result in damage to the disc, and sometimes, pain.

“It would be wonderful if we could get the cells in the intervertebral disc to regenerate or increase the amount of proteoglycans that they synthesize,” he says. “That way we could regenerate the shock-absorbing capabilities of the spine.” Dr. Risbud, an assistant professor of Orthopedic Surgery, and Dr. Shapiro, who is professor of Orthopedic Surgery, both at Jefferson Medical College, and their co-workers asked if it was possible to regenerate proteoglycans using adult stem cells. Federal regulations prevent them from using embryonic stem cells. Dr. Risbud built the study around the observation that while the tissue that he could isolate from the disc was no longer binding water, the tissue still might contain dormant stem cells. He thought that while these cells were no longer functioning to repair the damaged disc, under appropriate conditions, they could be activated.

To explore that possibility, he isolated cells from discarded disc tissue that still had the capacity to proliferate. Dr. Risbud notes that under certain conditions, the cells could be encouraged to form bone. In other conditions, the cells would form cartilage or even fat. The tests proved that these cells were indeed dormant disc stem cells. “If we are able to stimulate the ‘silent’ cells in the patient, then it may be possible to repair the ravages of degenerative disc disease without undergoing invasive surgical procedures that may limit the motion of the spine,” he says. According to Dr. Risbud, in earlier work, the researchers found that local conditions in the disc can promote adult stem cells of the bone marrow to acquire characteristics of disc cells. Within the disc, the local conditions are unique in that the oxygen levels are low. These conditions cause the expression of many specialized molecules, including the water-binding proteoglycans. Some of the researchers’ current experiments focus on the use of adult stem cells to repair the degenerate intervertebral disc.

Shapiro notes that other researchers have taken bone marrow stem cells and have made new bone, cartilage and fat tissue. “Our next step is to activate these disc stem cells and get them to repopulate the disc and make proteoglycans and restore the water-binding. The scientists theorize that because the stem cells exist in the degenerate disk, there may be molecules that are blocking stem cell activity. “Something is inhibiting the disc repair process,” says Dr. Shapiro. Drs. Shapiro and Risbud agree that “new studies are needed to discover the nature of such inhibitory molecules” and to find ways to block their activities, promoting natural healing.

Science Daily
November 12, 2007

Original web page at Science Daily

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Gastric bypass surgery may cause post-op nutrient deficiencies

Two studies by a group of researchers at Washington Hospital Center highlight potential postoperative nutritional deficiencies among patients who undergo gastric bypass surgery to treat obesity. Research presented at the 72nd Annual Scientific Meeting of the American College of Gastroenterology by Dr. Frederick Finelli and Dr. Timothy Koch suggests that a potentially serious condition can emerge after gastric bypass surgery known as small intestinal bacterial overgrowth that has an impact on absorption of vitamins, minerals and micronutrients such as calcium and zinc. According to the Washington Hospital Center team, this is a serious issue with widespread implications as approximately 150,000 patients this year will have gastric bypass surgery, and there exists wide variation in surgical techniques. According to Dr. Koch, “patients may develop bacterial overgrowth that interferes with their ability to absorb nutrients, even if they are taking supplements as directed after surgery. Only a gastroenterologist can evaluate these potentially serious small intestinal disorders.”

Dr. Koch and his colleagues hypothesized that by altering the gut ecology, gastric bypass surgery could induce calcium deficiency. Surgical changes to the stomach to create the “gastric pouch” in the Roux-en-Y procedure impact the number of acid producing cells in the stomach lining. Furthermore, many gastric bypass patients are given acid suppressing drugs after their surgery. Researchers suspect that the reduction in acid, known as achlorhydria, contributes to the overgrowth of bacteria in the small intestine. According to Dr. Koch, competition between bacteria and the human host for ingested nutrients leads to malabsorption and potentially serious complications due to micronutrient deficiency. In the studies presented at the ACG, Dr. Koch’s team found that in a retrospective review of gastric bypass patients, almost all of the 43 patients who had hydrogen breath testing for small intestinal bacterial overgrowth (“SIBO”) had abnormal findings. Researchers also measured levels of calcium and found that those with SIBO had lower calcium levels. Researchers warn that calcium malabsorption may increase the risk for developing osteopenia (low bone mineral density), osteoporosis (a progressive bone loss that may increase the risk of fractures), or osteomalacia (softening of the bones due to defective bone mineralization.)

In a second study, Dr. Koch and his colleagues reviewed that same group of patients to examine the relationship between SIBO and zinc deficiencies, and found a positive correlation. In the case of zinc absorption, the physiological evidence supports zinc absorption in the jejunum by a trancellular route involving a zinc-specific transporter, Zip4. In the Roux-en-Y procedure, surgeons make the stomach smaller by creating a small pouch at the top of the stomach using surgical staples or a plastic band. The smaller stomach is connected directly to the middle portion of the small intestine (jejunum), bypassing the rest of the stomach and the upper portion of the small intestine (duodenum). Dr. Koch explained that the wide variation in surgical techniques for gastric bypass means that patients should be aware of the risk of problems absorbing nutrients, and should consult with a gastrointestinal specialist.

Science Daily
October 30, 2007

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FDA approves knee-injury device for humans

A new knee-surgery device investigated by University of Missouri-Columbia researchers that will help to repair meniscus tears, which were previously defined as irreparable, has been approved by the FDA for use in humans. Previous treatment options forced surgeons to completely remove the damaged portion of the meniscus. Typically the removal of the meniscus leads to painful, debilitating arthritis in the knee. Herb Schwartz, president and CEO of Schwartz Biomedical, LLC, and James Cook, MU professor of veterinary medicine and surgery and William C. Allen Endowed Scholar for Orthopedic Research in MU’s College of Veterinary Medicine, developed the BioDuct Meniscal Fixation Device. Schwartz and Cook believe that patients with meniscus tears will now be able to have their meniscus saved along with long-term knee function. “In the past, when faced with meniscus injuries, surgeons were often forced to completely remove the torn meniscal cartilage, leaving a deficient knee that was doomed to develop arthritis,” Cook said. “With the BioDuct Meniscal Fixation Device, surgeons will be able to repair torn menisci and induce healing. People with meniscus injuries now have a better future ahead.”

The meniscus, a padding tissue that provides shock absorption and joint stability in the knee, is crucial for normal knee function. Surgeries for meniscus tears are common with approximately one million occurring in the United States each year. When meniscus function is deficient, bone rubs on bone and arthritis is likely to develop and progress. Because two-thirds of the meniscus is avascular (lacks a blood supply), a tear in that region will not repair itself. This new device will transport blood and cells from the vascular portion of the knee to the avascular portion of the meniscus. Supplied with blood and cells for healing, the previously untreatable meniscal tear now has the potential for allowing the knee joint to be saved. Cook’s research team performed the BioDuct surgery on 25 dogs that had worst-case scenario meniscal tears. With the BioDuct Meniscal Fixation Device, the meniscus in the dogs’ knees had complete or partial repair after a few weeks in all cases. “Currently, there are no other devices that can provide improved fixation over time,” Schwartz said. “Therefore, the BioDuct device is set apart from the rest of the field.”

In his research, Cook found that the device will significantly improve healing of avascular meniscal tears both biologically and biomechanically, which should lessen the long-term effects of meniscus injuries, including osteoarthritis. Cook’s recent findings were published in the American Journal of Sports Medicine. “The BioDuct device could impact the industry by improving repairs of the meniscus to such an extent that fewer patients develop arthritis that results from removing the meniscal tissue,” Schwartz said. “Thus, with fewer patients developing arthritis, the result could be fewer total joint replacements or at least delaying the need for a total joint replacement.”

Science Daily
October 16, 2007

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Certain tonsil removal technique associated with reduced postoperative pain, bleeding

Patients who have a tonsillectomy using an “intracapsular” technique–which removes at least 90 percent of tonsil tissue, but spares the tonsil capsule–appear to have less postoperative heavy bleeding and pain compared with those who undergo traditional tonsil removal surgery, according to a report in the September issue of Archives of Otolaryngology–Head & Neck Surgery. Tonsillectomy (removal of the tonsils) with or without removal of the adenoids (tissue at the back of the throat) is one of the most commonly performed surgeries in the United States, according to background information in the article. “The technique for performing tonsillectomy, dissection of all tonsillar tissue free of the underlying pharyngeal constrictor muscle, has not changed significantly in more than 60 years,” the authors write.

“The most common serious complication of tonsillectomy is delayed hemorrhage (severe bleeding), which occurs in 2 percent to 4 percent of all patients. In addition, an expected sequela (consequence) of the procedure is pain, which typically lasts from seven to 10 days and can be moderate to severe in intensity.” Richard Schmidt, M.D., and colleagues at the Alfred I. duPont Hospital for Children, Wilmington, Del., analyzed the medical records of 2,944 patients who underwent tonsillectomy with or without adenoidectomy between 2002 and 2005. For 1,731 patients, surgeons used a newer technique known as intracapsular tonsillectomy, which involves using an instrument known as a microdebrider to remove 90 percent of the tonsil tissue and preserving a layer of tonsil (the capsule) over the throat muscles. A total of 1,212 underwent traditional tonsillectomy, in which all tonsil tissue is cut and removed.

Among those in the traditional tonsillectomy group, 3.4 percent had delayed (more than 24 hours after surgery) hemorrhage and 2.1 percent required treatment in the operating room for bleeding, compared with 1.1 percent and 0.5 percent among those in the intracapsular tonsillectomy group. Three percent of those undergoing intracapsular tonsillectomy and 5.4 percent of those undergoing traditional tonsillectomy required emergency room treatment for pain or dehydration, which often occurs after tonsil surgery when pain restricts fluid intake. Eleven patients (0.64 percent) who had intracapsular tonsillectomies and none of those who had traditional tonsillectomies needed revision tonsillectomies. “The ideal tonsillectomy would have minimal or no risks and be completely effective,” the authors write. “Although the risks for intracapsular tonsillectomy are lower than those for traditional tonsillectomy, the procedure is not always effective. Eleven patients required revision tonsillectomy in the intracapsular tonsillectomy group compared with none in the traditional tonsillectomy group. However, an additional surgical procedure (including control of hemorrhage in the operating room) may be more likely with traditional tonsillectomy than with intracapsular tonsillectomy.”

Science Daily
October 2, 2007

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Natural aorta grafts have few side effects for infection-prone patients

A vascular surgery technique pioneered at UT Southwestern Medical Center, in which veins are removed from the thigh to repair the aorta does not create blood-flow problems and painful side effects in a majority of patients, researchers report. Vascular disease is a major contributor to life-threatening conditions such as aneurysms or blockages of the aorta. Inserting synthetic grafts to repair damaged aortas, the largest artery in the body, is typically the first line of treatment. Some patients, however, are prone to infections in these grafts, which typically requires removal of the infected grafts, a surgery that leaves the patient with no blood flow to the legs. Searching for a solution to this dilemma, surgeons at UT Southwestern, led by Dr. Patrick Clagett, chairman of vascular surgery, developed a technique in the early 1990s that uses veins from a patient’s own leg to fix and repair infected grafts.

Dr. Clagett and his colleagues recently reviewed the results of those grafts and found that patients had few side effects and fared well in the long-term after receiving grafts from their own bodies. He reports his findings in the September issue of the Journal of Vascular Surgery. Most patients with synthetic aortic grafts experience favorable outcomes, but for the small percentage of patients who develop chronic infections within the graft that do not respond to antibiotics, they are at risk of losing their legs or dying. “Since the veins of the leg return blood flow to the heart, there was concern that harvesting the deep veins from the thigh to repair synthetic aortic grafts could lead to problems with pooling of blood in the leg,” said Dr. Greg Modrall, associate professor of surgery at UT Southwestern and the lead author of the study. “Using the deep vein as an arterial graft, which was popularized by the senior author of this study, Dr. Clagett, has revolutionized the way we approach graft infections, and we were pleased to see few long-term side effects for patients who have received these grafts.” In addition, the researchers found that natural grafts are not nearly as prone to infection and later failure due to blockage of the graft.

The study examined 180 patients who underwent arterial reconstructions using deep-vein grafting at UT Southwestern. Of those surveyed, 85 percent reported no venous complications flow in the leg. A minority of patients (7.5 percent) reported mild swelling in the leg, and the remaining 7.5 percent reported moderate, but manageable, symptoms. “These results are astounding, particularly when one considers that most of the patients were facing life- or limb-threatening problems when they arrived at our institution,” Dr. Modrall said. In addition to a detailed interview, researchers performed a physical examination, ultrasound testing and venous physiological testing on each limb after deep-vein harvest. Few differences were noted between the legs that had been operated upon and those that had not. “Venous complications in the legs, known as venous insufficiency, can include swelling, skin discoloration and open wounds. We were reassured to find that even mild venous complications are quite unusual after removing the deep veins of the legs to treat these difficult graft infections,” Dr. Modrall said. “Our hope here is to reassure surgeons who face these complex cases that deep-leg-vein grafts are an acceptable — even preferable — alternative to replacing a synthetic graft with another synthetic graft.”

Science Daily
October 2, 2007

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Surgical technique helps to reanimate paralyzed faces

A surgical technique known as temporalis tendon transfer, in conjunction with intense physical therapy before and after surgery, may help reanimate the features of those with facial paralysis, according to a report in the July/August issue of Archives of Facial Plastic Surgery, one of the JAMA/Archives journals. “The rehabilitation of facial paralysis is one of the greatest challenges faced by reconstructive surgeons today,” the authors write as background information in the article. “It is an unfortunate fact that there is no ideal procedure that leads to the return of fully normal facial function. Furthermore, every case of facial paralysis is different in the cause of the paralysis, the degree and location of the paralysis and the resulting condition of the facial musculature and surrounding soft tissue envelope.” Many patients have excessive movement in some areas of the face and no movement in others; as a result, surgeons treating this condition must be able to perform multiple types of procedures and understand the underlying neurologic dysfunction.

Patrick J. Byrne, M.D., and colleagues at The Johns Hopkins University School of Medicine, Baltimore, report the results of seven facial paralysis patients treated with temporalis tendon transfer. This technique typically involves an incision beginning at the ear and ending 3 to 4 centimeters into the hairline at the temple. The temporalis muscle, a fan-shaped muscle on the side of the head, is cut at the point that it connects to the jawbone and released from the tissue surrounding it. Then, it is stretched to the point where the muscles of the mouth join together. The tendon that previously connected the temporalis muscle to the jawbone is cut free and then stretched horizontally for 3 to 4 centimeters; it is sutured to the surrounding muscles and deep skin tissue. Physical therapy to retrain facial muscles begins before the surgery and continues beginning seven days after the procedure.

At a minimum of four months after the surgery, “patient satisfaction was very high,” the authors write. “Of a possible 10 points, patients reported mean [average] satisfaction with appearance of 8.4, with feeding of 8.1, with speech of 8.7 and with smile function of 7.1.” Photographs taken of the patients were graded by 21 physicians in the Johns Hopkins Department of Otolaryngology–Head and Neck Surgery. “Four patients were physician-graded as excellent to superb. The other three patients were rated as having good postoperative results.” Movement in each patient’s mouth muscles was assessed by measuring the position of the muscles at rest and again when the patient contracted just the temporalis muscle. Movement was identified in all patients following the procedure, with measurements ranging from 1.6 millimeters to 8.5 millimeters and an average of 4.2 millimeters.

“Temporalis tendon transfer is a relatively easy procedure to perform that has distinct advantages compared with other forms of facial reanimation and provides very good results,” the authors conclude. These advantages include its immediate effect, the ease with which the tendon is harvested and transferred and the predictability of the outcomes. “This procedure results in improved form and function, may often be performed in a minimally invasive manner and eliminates the facial asymmetry typically produced by temporalis transfer,” a similar procedure in which only the temporalis muscle is moved.

Science Daily
September 4, 2007

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High-definition laparoscopic cameras have clear advantages in telesurgery

As a surgeon performs a minimally invasive procedure at Cedars-Sinai Medical Center in Los Angeles, surgeons observing in Boston or Mexico City or London will notice a remarkable improvement in clarity, compared to the view they would have had in the past. Cedars-Sinai has placed the most advanced high-definition cameras in two of its state-of-the-art operating rooms that are equipped to transmit images and audio in real time around the world for educational purposes. The miniaturized cameras are mounted at the ends of laparoscopes, instruments that enable surgeons to maneuver and operate inside a patient’s body through very small incisions. “Our surgeons are often invited to teach at international conferences, and the best way to teach, of course, is to be virtually there from the operating room,” said Edward H. Phillips, M.D., executive vice chairman of Cedars-Sinai’s Department of Surgery and chief of General Surgery. Cedars-Sinai is home to several pioneers in minimally invasive techniques, and the cameras are unlike any others in the Los Angeles area.

The high-definition cameras, manufactured by Karl Storz, one of the most respected producers of precision instruments and equipment, offer several benefits for surgeons performing operations and those viewing a procedure at another location. “Hemoglobin from blood absorbs light, and the present analog systems do not compensate well for this decrease in illumination. Also, red color saturation is less in high definition. The end result is that high definition enables the surgeon to see better when there is blood in the surgical field, which makes surgery safer,” said Phillips, who holds the Karl Storz Endowed Chair in Minimally Invasive Surgery in Honor of George Berci, M.D., one of the developers of minimally invasive techniques and technology. With the new cameras, surgeons can view the surgical field even when using a smaller diameter scope, which translates into smaller incisions and reduced pain. High definition also provides a wide-angle view, which allows surgeons to more quickly see instruments moving in and out of the surgical field, and depth of field is improved.

“You’re looking at a two-dimensional monitor but the visual clues that we use to judge depth of field, such as shadow and parallax — where a closer item appears bigger than one farther away — can be seen more clearly. We have shown in the surgical training lab that certain functions, such as tying knots and suturing, are improved because of the enhanced depth of field. There is less of what we call “sword fighting,” or moving around instruments before getting to the target,” Phillips said. Widely known for his expertise in minimally invasive procedures, Phillips and his colleagues recently completed a study on the use of high-definition cameras in laparoscopy and expect to publish their results in the near future. The operating rooms housing the new cameras are designed to provide X-rays and other images, data, and the most sophisticated technology at the surgeon’s fingertips.

Science Daily Health & Medicine
September 4, 2007

Original web page at Science Daily Health & Medicine