Articles filed under 'MEDICAL DISCOVERIES'
In recent years, several large studies have shown that quicker and cheaper “virtual colonoscopy†is a viable alternative to traditional colonoscopy. Although still considered “experimental†and not covered by most insurance for routine screening, the noninvasive X-ray procedure is available for those willing and able to pay the $1,100 cost. Traditional colonoscopy, the “gold standard†for many years, costs roughly $3,000.
Colonoscopy is recommended for persons 50 and over, but most don’t get them unless they are symptomatic. Instead, a sigmoidoscopy may be offered which checks only the lower bowel or intestine by inserting a flexible tube. Perhaps the most unpleasant part of any technique to explore the colon for polyps is drinking laxatives or using enemas to purge the bowel before the procedure.
Colon cancer is the second leading cause of cancer death in the U.S. and is largely avoidable by detecting and removing small polyps before they grow and become cancerous. Each year about 52,000 Americans die of the disease.
The latest study compared two groups of approximately 3,000 persons in each group. One group received traditional colonoscopy and the second one the virtual procedure. Approximately the same number of advanced polyps were found in each group (123 compared to 121).
With virtual colonography, a CT scanner takes a series of X-rays of the colon and creates a computerized 3-D image. A small tube is inserted in the rectum to inflate the colon for better viewing. There is no sedation or recovery time. If polyps are seen, they cannot be removed using this technique. Any significant polyps are then removed the same day using a traditional colonoscopy.
In traditional colonoscopy, a gastroenterologist uses a flexible, thin tube and snakes it through the large intestines. Any polyps spotted are removed in the process. There is a tiny risk of a perforated colon using the traditional procedure, and prompt surgical repair is needed.
The virtual colonoscopy avoids sedation and the risk of colon perforation, but the patient is exposed to radiation. In addition, small, benign polyps cannot be removed. They must be watched and will need to be removed if they grow significantly or become malignant.
If colon cancer screening guidelines are changed as is expected, virtual colonoscopy may be covered by insurance companies in the future. The less invasive procedure may encourage more patients to get checked when they should. Usually, intervals of ten years between examinations are recommended if no polyps are found.
Source:Â MSNBC
October 8th, 2007
A new test for prostate cancer, believed to be much more accurate than the PSA test, is expected to be approved soon. The test, currently undergoing large-scale clinical trials, measures the blood protein EPCA-2. Not only can it detect prostate cancer more effectively than measurement of prostate specific antigens (PSA), it also can determine the aggressiveness of the cancer and whether it has already spread.
In recent studies of 385 men, those with elevated EPCA-2 test results were found to have cancer 94% of the time, compared with 19% of those showing elevated PSA results. Only 3% showed false positive results and about 6% of existing cancers were missed using the new EPCA-2 blood protein markers. These results compare more favorably than the PSA test, which misses about 15% of existing cancers and gives a high level of false positives.
Every year, about 1.6 million men have unnecessary biopsies because of elevated PSA scores, whereas only about 230,000 of them actually are shown to have cancer. The digital rectal exam (DRE) is also not definitive in detecting this common cancer of men.
Prostate cancer is diagnosed in 230,000 new cases annually, and about 27,000 men die of the disease. The current PSA and DRE detection procedures are also deficient in that they cannot distinguish between cancer’s aggressive form, which is frequently fatal, and a slow-growing variety where “watchful waiting†may be the best strategy.
The new test could revolutionize the treatment of prostate cancer. It could save many lives and spare men with the slow-growing form of cancer from having unnecessary treatments in the future. Its manufacturer Onconome Inc., a Seattle Biomedical company, is developing the EPCA-2 test and expects the FDA to approve it by early next year.
Source:Â San Francisco Chronicle; Sunday, April 26, 2007; reporter Susan Brink of the Los Angeles Times
May 10th, 2007
The artificial hip is indeed a medical miracle, but the joint replacement surgery usually lasts only 20 years or so. Each year about 300,000 Americans undergo hip joint replacement surgery. As younger patients avail themselves of this type of hip surgery, the problem of “outliving†the joint replacement must be faced.
Middle-aged or younger people with hips damaged by disease or injury are often cautioned to put the surgery off as long as possible. In the meantime, many are plagued with pain and disability.
Now, an alternative surgical procedure may make the waiting game a thing of the past. Because extracting and replacing a worn-out or defective artificial hip is difficult, more surgeons are turning to hip resurfacing. Surgeons using this procedure preserve enough of the healthy bone to allow for a future total hip implant when benefits of hip resurfacing wear out.
In the past decade, tens of thousand of patients worldwide have undergone hip resurfacing. Many U.S. “medical tourists†had the procedure done overseas, where doctors are experienced in the technique and costs are lower. Popular destinations are Britain, Belgium or India, where costs may be half what they are in the U.S.
Hip resurfacing surgery is no easier for the patient or physician than hip replacement, and the incision is usually larger than with a total joint replacement. Complete healing can take six months or longer. The advantage is that the patient will still be eligible for a total hip replacement using an entirely new artificial joint rather than having a revision of the old one.
Hip resurfacing and total hip replacements both involve implanting a metal cup in the pelvic socket. The difference is mainly the way each procedure treats the top of the femur, the long thigh bone that fits into the socket. In resurfacing, the femur is shaved to a rounded shape and covered with a metal cap, with a spike that is cemented into a small hole drilled into the center of the femur.
With total hip replacement, surgeons saw off the entire head of the femur and replace it with a larger, hemispherical device that is anchored with a much longer spike and driven deeper into the femur. This procedure leaves too little strong bone to allow for follow-up with an entirely new total hip replacement if this joint wears out.
Hip resurfacing is not minor surgery. It requires a highly skilled surgeon, and the operation usually takes a bit longer than the three or four hours of total hip replacement. In addition, patients lose more blood, although transfusions are rarely needed.
With either procedure, problems can occur, but they are unlikely. Complications that are possible with either surgery include infections or fractures. Since hip resurfacing is so new, we are unlikely to know how durable the resurfaced hips are until the 20-year mark is reached in the earliest patients.
Doctors advise patients, especially younger ones, not to even think about either procedure unless they are in pain every day. Most people won’t want to take on the risks of either type of surgery, and the complications that could arise, just to improve their golf game or to be able to resume jogging.
Source:Â New York Times
April 16th, 2007
Researchers in Germany have used a technique called diffusion tensor imaging (DTI) in a study that examined brains of healthy volunteers and those with chronic back pain. They discovered that the brain in patients with chronic back pain had a more complex, active microstructure in regions associated with pain-processing, emotion and stress response.
The study findings were presented at the annual meeting of the Radiological Society of North America, held in Chicago recently. Researchers indicated that DTI demonstrates chronic pain is real and could help treatment research. Patients who suffer back pain sometimes have difficulty convincing their physicians, relatives, and insurance carriers of their genuine distress. Spinal MRI images do not always clearly demonstrate the source of pain.
According to the lead researcher, a radiologist in Munich, Germany, the objective and reproducible correlates in brain imaging should change the way chronic pain is perceived. It need no longer be a subjective experience. For pain diagnosis and treatment, the consequences could be huge. As a result, clinicians may direct therapeutic attention from the spine to the brain.
What is unclear is whether the brain in certain individuals is predisposed to developing chronic pain, whether ongoing pain causes hyperactivity and change in the brain’s organization or a combination of both.
Physicians who treat patients with chronic back pain have long known that chronic pain can begin with a serious injury. Even after healing has occurred, the brain continues to send pain signals for these individuals. The new imaging technology DTI will be able to validate their theory that the nervous system has been “rewired.â€
This study adds to the growing body of research showing that chronic pain is associated with physical changes in the brain. Chronic is defined as lasting more than six months.
In some cases, back pain plagues individuals for many years after their initial injuries.
This study helps the medical community to understand how the central nervous system is involved in back pain. More research is needed to determine what the brain’s physical changes mean and how to most effectively treat the pain.
Source:Â BBC News
February 20th, 2007
Women with very dense breast tissue are five times more likely to get breast cancer than those whose breasts contain more fatty tissue, according to a recent study. Doctors should discuss this particular risk factor with their patients who have mammograms.
Fat appears dark on mammograms, but dense tissue is light like tumors, thus more easily hiding cancers. Not only are breast cancers more likely to be hidden by white on white, they also appear more frequently in dense breasts.
Density is a true risk factor, along with other strong predictors such as the woman’s age and whether she carries BRCA1 and 2 gene mutations. Yet, this condition is rarely taken into consideration or discussed between doctor and patient.
This new study — involving 1,112 women whose medical records were examined at cancer centers in Toronto and Vancouver, Canada — is published in a January 2007 issue of the New England Journal of Medicine. Women taking part who had at least 75% dense breasts showed five times more likelihood of developing cancer over the time frame studied than women with less than 10% density. It confirms previous studies that pointed to the masking effect and a separate biological risk.
In this particular study, cancers were 18 times more likely to be found in women with the densest breasts within the first year after their mammograms. These cancers were judged to have been present earlier but masked by the difficulty in diagnosing their condition.
Breast density involves the presence of more connective, duct-lining and milk-gland tissue than fat tissue. It is impossible for a woman to judge the density herself. It must be routinely evaluated with a mammogram.
This most important factor to note is that extremely dense breaks are “an incredible risk factor†that probably accounts for a large percentage of breast cancers being found. Woman whose mammograms indicate dense breast tissue should be followed up rapidly with more sensitive technologies such as digital mammograms, sonograms or magnetic resonance image (MRI).
Some medical experts believe that women with this significant risk factor may be one day be cautioned to make lifestyle changes and even be prescribed medications for cancer prevention. If genes that promote density can be identified, they could serve as targets for cancer drugs.
Source:Â Associated Press; CNN HealthÂ
January 20th, 2007
A simple blood test measuring the amount of a protein called NT-proBNP was recently shown to be highly predictive of cardiovascular events in patients with established coronary heart disease.
In a study of almost 1,000 heart patients believed to have stable heart disease, those with the highest blood levels of the protein were eight times more likely to have a heart attack, stroke or heart failure during the 3.7-year study than those with the lowest levels of NT-proBNP.
Among the study participants, patients with highest NT-proBNP level had the strongest association with heart failure. Eighty cases of heart failure were reported during the study, compared with only three cases among patients with the lowest protein levels. There were four times as many heart attacks and four times as many strokes in study patients with the highest NT-proBNP levels, compared to those with lower protein measurements.
The test is already in use in hospital emergency departments to assist ER doctors in identifying heart failure in patients presenting with shortness of breath and other established symptoms. In addition to echocardiograms, stress tests, and other protein biomarkers, the new blood test may be able help physicians to pinpoint heart patients with the highest risks.
Looking at other risk factors such as sex, age, smoking, and elevated cholesterol levels, this new maker provides additional information that other tests don’t reveal. It is still unclear, however, whether the test is valuable for predicting risk in asymptomatic heart patients thought to have stabilized their heart disease.
Also unknown is whether the test could prove useful for identifying heart disease risk in the general public. At this point, it is best utilized with patients with established heart disease. Its role in disease management is still not clear. Those with elevated NT-proBNP can be treated very aggressively, but most patients with serious heart conditions are already being treated in that manner.
More study is needed to determine the value of the NT-proBNP test, the subject of the study at the University of California, San Francisco and the San Francisco VA Medical Center.
Source:Â WebMD
January 11th, 2007
Doctors may fail to ask their older patients about sleep difficulties, or it they are mentioned, neglect to enter them in the person’s medical chart. A study involving 1,500 participants aged 60 or older from 11 primary care sites backs up this premise. While 69% mentioned at least one sleep complaint, their concerns in this area were recorded only 19% of the time by their physician.
Independent social workers interviewed study participants (seniors) after their doctors’ visits and learned that the majority had difficulty falling asleep, staying asleep or being able to sleep. Doctors may believe sleep difficulties to be a normal part of aging, and patients may neglect to mention the problem at their medical examination.
Several studies have shown that not getting enough sleep can lower a person’s metabolic function, be associated with cardiovascular problems, breast cancer in women and increased sensitivity to pain. Insufficient sleep may also result in depression, or depression can cause sleep difficulties. Which comes first is unknown.
Sleep disorders are easily treated by newer prescription medications or by teaching “sleep hygiene†techniques. Meditation, exercise, and modifying the evening activity before bedtime can also help produce sounder sleep. Treating sleep disorders effectively results in improved health and quality of life.
Excessive daytime sleepiness is often the best predictor of poor physical and mental health. Physicians would do well to ask a patient ,â€Do you feel sleepy during the day?â€
This question will open the door to pursuing further questioning about a patient’s quality of sleep.
This most recent study from the Feinberg School of Medicine at Northwestern University is published in the American Journal of Geriatric Psychiatry.
Source:Â Medical News TODAYÂ Â
January 11th, 2007
Low back pain sufferers can look forward to a potential cure for their damaged disks and resulting pain. A research team at the University of Manchester, England, hopes that the new, patented treatment can be available within three years.
The therapy, developed by Dr. Stephen Richardson, would use injected adult stem cells taken from the patient’s own bone marrow. These mesenchymal stem cells (MSCs) have the ability to differentiate into many different cell types. The extracted stem cells are then embedded in a gel-like material where they are grown in a culture. The gel-like substance is similar to natural collagen already used to treat cartilage defects.
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Dr. Richardson has been successful in turning MSCs into cells that make up the nucleus pulposus (NP) to provide cushioning between vertebrae. Because the stem cells are harvested from the patient’s own body, there is no chance of rejection by the immune system.
The British medical team reintroduces the cultured material into the damaged spinal disks through a tiny incision and using an arthroscope. The patient should be able to return home the same day after the procedure or the following day.
With treatments currently available to treat debilitating low back pain, success may be limited, and the cause of the pain is not completely addressed. This new procedure is expected to correct the root cause of the pain and give welcome relief from symptoms.
Pre-clinical trials will begin next year, after which full patient trials will take place. Although still in the early stages of development, the treatment appears very promising based on initial results.
Source:Â BBC News
December 2nd, 2006
In early studies, an experimental device resembling a tiny pacemaker has been shown to control blood pressure more effectively than medications. For 10 to 15% of patients with high blood pressure, medications are not helpful.
High blood pressure consists of a reading of 140/90 mm Hg or higher. Also called hypertension, high blood pressure is a major risk factor for heart disease or stroke.
The new “pacemaker-type†device is currently being studied by the chief of vascular surgery at the University Hospital in Berne, Switzerland, in patients who do not respond to available medications.
Surgeons place electrodes outside the carotid artery and implant an internal pulse generator into the chest wall. Using electrical current to stimulate the carotid sinus, messages are sent to receptors in the brain. Preliminary results have shown remarkable results in a swift drop of blood pressure.
The first 16 patients experienced an average drop of 29 millimeters of mercury after receiving the new device. In patients taking drugs, reducing their blood pressure by
9 millimeters is considered an outstanding result. Researchers call the device, developed by Minneapolis-based CVRx, “very promising.â€
Source: Oakland Tribune    November 2006
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November 24th, 2006
An inexpensive new test uses computer technology to gauge the risk of sudden cardiac death. The test of the heart’s electrical system in individuals with history of heart damage helps doctors decide who needs an implanted cardioverter defibrillator (ICD).
When a person with an ICD experiences dangerously abnormal cardiac rhythm, the device delivers an electrical jolt that shocks the heart back to normal rhythm. Sudden cardiac death kills about 325,000 adults in the U.S. each year – primarily persons who do not have the implanted device.
Until now, cardiac screening of large populations for risk of sudden cardiac death has been expensive and impractical. This new technology could make such screenings more affordable and feasible.
A study involving 500 patients with some heart damage using the more invasive electrophysiological screenings as well as the new, computerized technology came to a close recently. The new testing techniques proved to be just as accurate, according to a professor of medicine at the American Heart Association’s annual meeting.
In the older test, a catheter is inserted through a small incision in the vein and threaded to the heart to measure electrical activity. The new test, called the microvolt T wave alternans (MTWA), measures the electrical discharge of a person’s T-waves from one beat to the next. This individualized risk information allows doctors to determine which patients might benefit from an implanted ICD.
The predictive accuracy of both tests is comparable. The main difference is that the latest test is simple, noninvasive and cheap, while the other is invasive, expensive and risky. In complicated cases, some doctors use both tests. When both technologies confirm the need for an ICD, the surgery is performed.
Physicians hope that in the future, the newer technology may be able to replace electrophysiological screening altogether. At this point, two tests are still better than one.
Source:Â WebMD
November 22nd, 2006
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