Eye exam could detect Alzheimer’s
A simple and inexpensive eye test could detect Alzheimer’s before it develops, scientists have claimed.
Researchers at the University College London (UCL) believe that in the future the new technique could be performed at the opticians.
Having been successfully trialled on rats and mice, tests on humans are planned for later this year.
Published in Cell Death & Disease, the procedure enables retinal and brain cell death to be directly measured in real time. It uses florescent markers which attach themselves to the relevant cells and indicate their stage of death. The retina can then be observed through a customised laser ophthalmoscope, allowing diagnosis of the condition to be made earlier and making it easier to track its progression.
Lead author professor Francesca Cordeiro said: “It’s entirely possible that in the future a visit to a high-street optician to check on your eyesight will also be a check on the state of your brain.”
She then explained: “The death of nerve cells is the key event in all neurodegenerative disorders – but until now it has not been possible to study cell death in real time. This technique means we should be able to directly observe retinal nerve cell death in patients, which has a number of advantages in terms of effective diagnosis. This could be critically important since identification of the early stages could lead to successful reversal if the disease progression with treatment.”
News | Comment (0)Steroid Injections May Slow Diabetes-Related Eye Disease
Researchers led by specialists at the Johns Hopkins Wilmer Eye Institute have found that injecting a corticosteroid, triamcinolone, directly into the eye may slow the progression of proliferative diabetic retinopathy, a complication of diabetes that frequently leads to blindness.
Authors of the study caution, however, that because use of steroids in the eye may increase the risk of glaucoma and cataract, laser photocoagulation remains the treatment of choice until further development of drugs that may reproduce the good effects of steroids, without the damage.
“Steroid treatment worked, but because of safety issues, cannot be recommended routinely at this time,” says Neil M. Bressler, the James P. Gills Professor of Ophthalmology and chief of the Retina Division of the Johns Hopkins Wilmer Eye Institute, chair of the government-sponsored Diabetic Retinopathy Clinical Research Network. “It is a condition that can be treated safely and effectively with lasers.”
The study, published in the December issue of the Archives of Ophthalmology, described and compared one of two treatments on 840 eyes from 693 men and women between July 2004 and May 2006. The subjects, about evenly divided between men and women with an average age of 63, had diabetic retinopathy with macular edema, a swelling of the central portion of the retina that’s caused by leakage of fluid.
Proliferative diabetic retinopathy is marked by the growth of new and unwanted blood vessels on the optic nerve in the back of the eye (which communicates information from the retina to the brain) or another area of the retina, the light-sensitive part of the eye. Despite advances in treating both diabetes and its complications, about 700,000 Americans have proliferative diabetic retinopathy and 63,000 new cases develop each year.
In the study, each patient’s eyes were randomly assigned to receive either a laser treatment (photocoagulation) for diabetic macular edema or an injection (1 or 4 milligrams) of triamcinolone acetonide directly into the eye as often as every four months.
According to Bressler, lead author of the study, there was some evidence that steroids could improve vision outcomes from diabetic macular edema (DME), swelling of the center of the retina, the part of the retina used for reading or driving. Study results showed that steroids were not superior to laser treatments for DME.
“The primary objective of the study was to determine if steroids were superior to laser for DME, and if so, to balance that superiority with steroids’ side effects. A secondary objective was to determine if the steroids affected the progression of diabetic retinopathy,” adds Bressler. “Steroid treatments did reduce the risk of progression of diabetic retinopathy, but, not DME, which can also cause vision loss from proliferative diabetic retinopathy, bleeding in the middle cavity of the eye or scarring of the retina, which can detach the retina from the back wall of the eye.”
The steroid injections were not superior to laser with respect to increasing the chance of improved vision and decreasing the chance of vision loss, the primary objective of a study reported in 2008. “However, there was evidence that steroids can affect the pathways that lead to the development of new blood vessels on the surface of the retina in diabetes, a secondary objective of the study” says Bressler. “Controlling blood glucose levels can help prevent the development of retinopathy and laser treatments can reduce the risk of vision loss, but the identification of other treatments remains important.“
Bressler and colleagues, in the Diabetic Retinopathy Clinical Research (DRCR) Network, discovered that after two years, retinopathy had progressed in 31 percent of 330 eyes treated with laser treatment, 29 percent of 256 eyes treated with 1-milligram doses of triamcinolone acetonide, and 21 percent of 254 eyes treated with 4-milligram doses. The differences appeared to be sustained at three years, even though most eyes in the triamcinolone groups did not receive injections every four months during the second year and less than half received any injections in the third year because there no longer was macular edema, or less commonly, because side effects from the injections precluded applying additional steroids when following the study’s treatment protocol.
Bressler says the study suggests that corticosteroids interfere with the creation of new blood vessels by reducing the production of compounds that spur their growth and cautions that steroids are also associated with other eye diseases. “Researchers now need to find ways of using the steroid effect on these blood vessels for treatment, but, not at the expense of causing glaucoma and the side effects of cataract formation or worsening of cataracts which could lead to the need for a patient to undergo cataract surgery.”
Other investigators who authored the study for the Diabetic Retinopathy Clinical Research Network include Allison R. Edwards, M.S., Roy W. Beck, M.D., Ph.D., Christina J. Flaxel, M.D., Adam R. Glassman, M.S., Michael S. Ip, M.D., Craig Kollman, Ph.D., Baruch D. Kuppermann, M.D., and Thomas W. Stone, M.D.
The study was supported through a cooperative agreement from the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health, part of the Department of Health and Human Services. Allergan Inc. provided the preservative-free triamcinolone acetonide and topical antibiotics as requested by the DRCR Network and unrestricted funds to the DRCR Network. Following the Network’s Industry Collaboration Guidelines to maintain academic integrity, the DRCR Network had complete control over the design of the protocol, ownership of the data and all editorial content of presentation and publications related to the protocol.
News | Comment (0)Omega-3s Help Stave off Age-Related Vision Loss
Want to keep your eyesight sharp as you age? Eating lots of fish packed with healthy omega-3 fatty acids could help, new research suggests.
Among 1,837 people who had early signs of age-related macular degeneration (AMD), those with the highest consumption of omega-3 fatty acids were 30 percent less likely to progress to the advanced form of the disease over a 12-year period than those with the lowest omega-3 intake, researchers found.
Dr. John Paul SanGiovanni of the National Eye Institute at the National Institutes of Health in Bethesda, Maryland, and his colleagues report their findings in the December issue of the American Journal of Clinical Nutrition.
AMD is a deterioration of the retina that is the leading cause of vision loss among older US adults.
About 1.75 million Americans and 3.35 million Europeans have AMD severe enough to impair their vision, according to the researchers.
While there are some drug treatments for the disease, they add, these medications have limited effectiveness, are expensive, and can lead to serious complications. Because inflammation is likely to be involved in AMD progression, and omega-3 fatty acids have anti-inflammatory effects, they add, these nutrients have the potential to help slow the progress of disease.
To investigate, SanGiovanni and his colleagues analyzed data from the Age-Related Eye Disease Study, a clinical trial run by the National Institutes of Health to investigate nutrition-based approaches to preventing and treating AMD. All of the study participants were free of advanced AMD in at least one eye, but did have some degree of earlier stage disease.
Over the course of 12 years, about 20 percent of people in the current study developed “dry” AMD, in which the tissue at the center of the retina disappears. Another 32 percent developed “wet” AMD, or neovascular AMD, in which abnormal blood vessels grow in the macula.
People who consumed the largest amounts of the two main dietary types of omega-3 fatty acids — docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) — were about 30 percent less likely to develop either wet or dry AMD than people with the lowest intake, the researchers found.
Those who consumed the most DHA and EPA got about 11 percent of their calories from omega-3s, compared to about 1 percent for people with the lowest intake.
“Our results, if confirmed by other studies and extended by clinical trials, may guide the development of low-cost, easily implemented, and widely accepted interventions to prevent the progression to advanced AMD,” SanGiovanni and his team conclude.
News | Comment (0)Stem Cells May Hold Hope for Eye Disease
New research has found that a certain kind of stem cell from human umbilical cords helped restore transparency to the cloudy corneas of laboratory mice, raising the prospect that they could do the same for people.
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Currently, a limited supply of donated human corneas is available to help people with severe corneal and eye diseases.
The new research examined human umbilical cord mesenchymal stem cells. When transplanted into the corneal stroma of the mouse eyes, they survived for more than three months without much sign of graft rejection, researcher Winston Kao of the University of Cincinnati School of Medicine, said in a news release from the American Society for Cell Biology.
Transplantation of human organs involves a certain degree of risk because the body tries to reject things it considers foreign. In the study, that happened to another kind of stem cell — human umbilical hematopoietic stem cells — that was transplanted into the mouse eyes.
However, according to Kao, stem-cell transplants hold promise as a treatment for some eye diseases. He said it’s easy to isolate the cells and let them reproduce before storage, and the supply of stem cells is virtually unlimited.
The findings were to be presented Dec. 8 at the American Society for Cell Biology’s annual meeting in San Diego.
News | Comment (0)Some Help in a Transition and a Recovery From Eye Surgery
There are moments in the telling of his story, particularly when he tries to describe the excruciating pain he suffered as a result of eye surgery gone awry, that Raul Mejia must stop and gather himself before going on.
“I don’t want to even remember this situation because, in reality, it was a very difficult moment in my life,” he said during a recent interview. “I ask forgiveness from God, but I really wanted to die.”
Mr. Mejia, 60, immigrated to the United States from the Dominican Republic in 1974 seeking, as so many other immigrants have done, a better life. His wife, who was pregnant with their first son, stayed behind in Santo Domingo, surviving with the help of remittances from his paychecks from his work in building maintenance and security and auto parts sales.
Mr. Mejia eventually secured American citizenship and, in 1985, brought his wife and boy to the United States. Two years later, they had their second boy, and Mr. Mejia found steady work as a limousine driver, a job he held until he developed eye problems.
The couple separated in 2002. Mr. Mejia moved into a furnished room in the basement of a single-family home in Corona, Queens; his ex-wife remained in the family’s apartment in Flushing. Though depressed, he was determined to press ahead and help achieve a good, secure life for himself and his children.
His plan had another setback on July 26, 2008, when he started experiencing double vision. He consulted with a doctor who told him there was a problem with an intraocular lens that had been implanted in his right eye during cataract surgery in 2000. On July 31, he underwent replacement lens surgery at a Manhattan hospital.
“The doctor said it would take 20 to 25 minutes,” Mr. Mejia recalled. But complications arose, and the surgery took four hours. He says the doctors never told him what had happened.
Mr. Mejia was discharged, but for the next two weeks he suffered extreme pain. “It was like a saw cutting my eye,” he said, wincing at the memory. “It was the worst time of my life.” Despite daily visits to the hospital and consultations with at least 15 doctors, the pain did not ebb and its cause was never fully diagnosed, he said.
The lingering problems also meant he could not return to work.
Finally, Mr. Mejia sought the opinion of a doctor at a private eye clinic in Flushing, who took one look at his eye and declared an emergency: The cornea was damaged and pieces of an intraocular lens were embedded in different parts of the eye — “as if a glass had broken,” Mr. Mejia said.
In the ensuing five months, he underwent four more operations, including a transplant to replace the cornea damaged by the lens fragments. As he describes one process — a cleaning beneath the cornea, to remove any pieces of the broken lens — he closes his eyes and takes a deep breath: The thought alone seems to sicken him.
He followed a regimen of medication and doctor’s appointments. His vision in his troubled eye steadily improved and the pain began to fade, though he was still not able to return to work.
He sought the help of the Federation of Protestant Welfare Agencies, one of the seven beneficiary agencies of The New York Times Neediest Cases Fund, which helped him secure a Section 8 voucher in January 2009, enabling him to move from his $300-per-month basement bedroom to a new apartment. He found a studio in a low-income residential building in Elmhurst, Queens, and received a grant from the Bridge Fund of New York City to cover the $2,106 in moving costs and security deposit.
Relatives, friends and charities donated furniture. A grant of $1,259 from Neediest Cases Fund allowed him to buy a queen-size bed, nightstands, a bureau, a chest of drawers and a mirror.
He is currently receiving $781 per month in Social Security and disability benefits and $200 per month in food stamps, he said; his portion of the studio’s monthly rent is $94.
“Now I can see little by little,” he said.
Mr. Mejia does not know when, or even if, he will be able to return to his limousine job. For now, he said, he is hoping that his ordeal is nearing an end.
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