Common Eye Problems Include Macular Degeneration and Cataracts

Few 40-year-olds' to-do lists include "Be proactive about not going blind," so you might have to play catch-up. Age 40 really is the time to start protecting your eyes against serious diseases such as glaucoma and macular degeneration, neither of which has symptoms in the early stages. (That's in contrast to the loss of close-focus vision that forces 45-year-olds into bifocals but doesn't threaten blindness.) "Patients may go to the drugstore and get these over-the-counter reading glasses and think, 'Hey, I've fixed my eyes,' " says Andrew Iwach, an ophthalmologist who is executive director of the Glaucoma Center of San Francisco. "Yet they may be unaware that they can be silently losing vision."

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The best defense: a comprehensive eye exam that screens for glaucoma, macular degeneration, diabetic retinopathy, and cataracts. (And no, passing your driver's license retest doesn't count.)

Cataracts are the most common age-related eye disease, with more than 17 percent of Americans age 40 and over affected. The main cause, aside from plain old aging, is exposure to ultraviolet B radiation in sunlight. Wearing sunglasses and brimmed hats while outside can reduce exposure and delay the need for surgery to remove a clouded lens. The good news is that cataract surgery has been refined so that the supersmall incisions are self-sealing; new artificial lenses can be folded or rolled and slipped into place.

Glaucoma and macular degeneration are more insidious conditions; by the time you know you're a victim, vision has often been lost forever. In glaucoma, the optic nerve becomes damaged, and vision loss usually starts at the side. Most people with glaucoma have increased pressure inside the eyeball, and although it's unclear how that pressure affects the optic nerve, medications that lower the pressure are effective at slowing damage.

With age-related macular degeneration, the macula, a spot in the center of the retina that provides clear central vision, is damaged by abnormal blood vessel growth or slow loss of light-sensitive cells. High doses of supplements, including vitamins C and E and beta carotene and the mineral zinc, have been found to slow the progression of AMD in several trials. But because some studies have linked high doses of beta carotene and vitamin E to cardiovascular risks, ophthalmologists advise against taking supplements as a preventive measure unless they're doctor-prescribed. It's impossible to get that quantity of antioxidants and zinc in food alone, but some studies have found that people who eat a lot of dark-green leafy vegetables have a lower risk of AMD. Smoking increases the risk of macular degeneration, so there's one more reason to quit.

People with diabetes have added reason to worry: Diabetic retinopathy affects some 40 percent of people with the disease, with 8 percent of all diabetics facing significant vision loss. Keeping your blood sugar levels under control reduces the risk of harm.

By Nancy Shute

Copyright © 2009 U.S.News & World Report LP All rights reserved.

One-third of U.S. seniors have diabetes

Understanding that Diabetes is a leading cause of vision loss in the U.S., the following release is a reminder as to the importance of routine medical checks...

BETHESDA, Md., Jan. 27 (UPI) -- Nearly one-third of U.S. adults age 65 and older have diabetes, while an additional 30 percent have pre-diabetes, researchers said.

"We're facing a diabetes epidemic that shows no signs of abating, judging from the number of individuals with pre-diabetes," lead author Catherine Cowie of the National Institute of Diabetes and Digestive and Kidney Diseases, a part of the National Institutes of Health said in a statement.

"For years, diabetes prevalence estimates have been based mainly on data that included a fasting glucose test but not an oral glucose tolerance test," Cowie said in a statement. "The addition of the oral glucose tolerance test gives us greater confidence that we're seeing the true burden of diabetes and pre-diabetes in a representative sample of the U.S. population."

The oral glucose tolerance test gives more information about blood glucose abnormalities than the fasting blood glucose test, which measures blood glucose after an overnight fast. The fasting blood glucose test is easier and less costly than the oral glucose tolerance test , but the two-hour test is more sensitive in identifying diabetes and pre-diabetes, especially in older people, Cowie explained.

The 2005-2006 National Health and Nutrition Examination Survey is the first national survey in 15 years to include the oral glucose tolerance test.

The study, published in Diabetes Care

, also found 13 percent of adults age 20 and older have diabetes, but 40 percent of them have not been diagnosed.

© 2009 United Press International, Inc. All Rights Reserved.

First Embryonic Stem-Cell Trial Gets Approval From the FDA

By RON WINSLOW and ALICIA MUNDY

In a watershed moment for one of the most contentious areas of science and American politics, the U.S. Food and Drug Administration cleared the way for the first-ever human trial of a medical treatment derived from embryonic stem cells.

Geron Corp., a Menlo Park, Calif., biotechnology company, is expected to announce Friday that it received a green light from the agency to mount a study of its stem-cell treatment for spinal cord injuries in up to 10 patients. The announcement caps more than a decade of advances in the company's labs and comes on the cusp of a widely expected shift in U.S. policy toward support of embryonic stem-cell research after years of official opposition.

"This is the dawn of a new era in medical therapeutics," said Thomas B. Okarma, Geron's president and chief executive officer. The hope that stem-cell therapy will repair and regenerate diseased organs and tissue "goes beyond what pills and scalpels can ever do."

Limits on stem-cell research, which prevented federal funding and were imposed by Congress and former President George W. Bush for ethical and religious reasons, have had a chilling effect on both academic and corporate research involving such cells. Proponents of stem-cell research say restrictions have delayed development of promising new treatments, while critics contend that harvesting stem cells from embryos destroys human life.

President Barack Obama said during his campaign that overturning research limits would be a top priority in his administration.

Both Geron and the FDA said the timing of the decision to approve the study was coincidental. "The FDA looks to the science on these types of issues, and we approve [such applications] based on a showing of safety," said Karen Riley, an FDA spokeswoman. "Political considerations have no role in this process."

Approval of the study is far from a guarantee that stem-cell treatments will work or make it to the market, but it is likely to be seen as an indication that opportunities for stem-cell research are poised to open and will fuel enthusiasm among academic and corporate researchers.

Mr. Obama's plans for acting on the current research restrictions haven't been finalized. Shortly after the election, Obama advisers thrilled biotech companies and investors when they suggested that the new president could use his executive authority to undo the Bush administration ban. But in a Jan. 18 interview on CNN, Mr. Obama said he might let Congress take the lead. "I like the idea of the American people's representatives expressing their views on an issue like this," he said.

Regulating stem-cell therapy is new turf for both industry and the FDA, a major reason why it took the agency nearly a year to review Geron's 21,000-page application for the trial, which it filed last March. Approval came in a phone call Wednesday afternoon, Dr. Okarma said.

The study will focus on the safety of the treatment. At an FDA hearing in April, several firms' executives and researchers complained that they were at a loss about what the FDA wanted in terms of clinical trials involving stem cells because the FDA itself wasn't sure.

Embryonic stem cells are the building-block cells that help drive prenatal development. Geron has developed banks of embryonic stem cells and found a way to coax them into differentiating as they do in nature into progenitors of specific cells that make spinal-cord tissue, heart muscle, cartilage and other organs and tissues.

Spinal-cord injury is one of medicine's most debilitating conditions, typically causing paralysis and other issues for which there are few, if any, effective treatments. The Geron study will enroll paralyzed patients who can be treated within 14 days of their injury. Patients will be evaluated for at least one year, after which, if the treatment proves safe, the company hopes to increase the dose and expand the potential candidates for the therapy.

In addition to safety, researchers will look for signs that the treatment is effective.

Printed in The Wall Street Journal, page A12

Write to Ron Winslow at ron.winslow@wsj.com and Alicia Mundy at alicia.mundy@wsj.com

Protease inhibitor found to aid diabetic retinopathy treatment

The study, which was partly funded by the Juvenile Diabetes Research Foundation (JDRF), is published in the February 2009 issue of the journal Hypertension .

In the published study, led by Edward P. Feener, Ph.D., an Investigator in the Section on Vascular Cell Biology at the Joslin Diabetes Center and Associate Professor of Medicine at Harvard Medical School, continuous systemic administration of ASP-440 proved effective in decreasing hypertension-induced increased retinal vascular permeability in rodents, by as much as 70%. Increased retinal vascular permeability is a characteristic finding in diabetic retinopathy and a primary cause of diabetic macular edema, a leading cause of visual impairment associated with diabetes. Hypertension is a known risk factor for the development of retinopathy. ASP-440 was also found to be effective in lowering the elevated blood pressure in these animals.

"These findings represent a pivotal step towards understanding the importance of plasma kallikrein as a target in diabetic eye disease and how its inhibition may support the development of a safe and effective therapy for diabetic retinopathy," said Barbara Araneo, Director of Complications Research for the Juvenile Diabetes Research Foundation. "While further studies are needed to determine the therapeutic potential of ASP-440, the research underscores the relevance of the kallikrein system in diabetic microvascular disease."

In previous JDRF-funded research, Joslin researchers identified plasma kallikrein as a potential therapeutic target in people with diabetic retinopathy. "This recent study suggests new opportunities to inhibit plasma kallikrein and reduce retinal blood vessel leakage," said Dr. Feener. "While these results are encouraging, more work is needed to understand plasma kallikrein's role in other retinal functions, as well as other diabetic complications, which can occur concurrently with diabetic retinopathy."

"We are very encouraged by the pharmacological activity demonstrated by ASP-440 in this model of hypertensive retinal vascular permeability," said Tamie Chilcote, Ph.D., Vice-President, Lead Discovery, for ActiveSite Pharmaceuticals. "We look forward to further studies in collaboration with Dr. Feener to better establish the therapeutic potential of this and other plasma kallikrein inhibitors for treatment of retinopathy."

Diabetic Retinopathy

Diabetic retinopathy is the most common and most serious eye-related complication of diabetes. It is a progressive disease that causes retinal swelling and destroys small blood vessels in the retina, eventually leading to vision problems. In its most advanced forms, known as "diabetic macular edema" and "proliferative retinopathy," it can cause moderate to severe vision loss and blindness. Nearly all people with type 1 diabetes show some symptoms of diabetic retinopathy usually after about 20 years of living with diabetes. Approximately 20 to 30 percent of patients develop the advanced form. Those with type 2 diabetes are also at risk.

Over time, the disease progresses to its advanced or proliferative stage, and fragile new blood vessels grow along the retina. However, these fragile vessels can hemorrhage easily, and blood may leak into the retina and the clear, gel-like vitreous that fills inside of the eye. Unless quickly treated, this can result in spots, floaters, flashes, blurred vision, vision loss, and even temporary blindness. In later phases of the disease, continued abnormal vessel growth and the formation of scar tissue may cause serious problems such as retinal detachment and glaucoma, both of which can cause permanent blindness. Diabetic macular edema, which involves swelling in the retina that transiently or permanently impairs vision, can occur at any stage of diabetic retinopathy. Treatment to prevent or reverse this condition remains a major unmet clinical need.

http://www.jdrf.org/

Version 2.0 Copyright © 2009 News-Medical.Net

Stem cell eye surgery to be tried

A new surgical treatment offering hope to patients with corneal blindness is to be trialled in Scotland.

Doctors in Edinburgh and Glasgow will work together using an innovative technique involving adult stem cells.

About 20 patients will take part in the initial tests, using cells cultivated before being transplanted onto the surface of the cornea.

Millions of people worldwide suffer from corneal blindness, 80% of whom are elderly.

Stem cells are a source of great scientific interest as a result of their ability to renew and multiply indefinitely, potentially regenerating entire organs from only a few cells.

Unlike the more controversial embryonic stem cell research, the technique takes stem cells from dead adult donors.

The trial is being led by Prof Bal Dhillon at the Princess Alexandra Eye Pavilion in Edinburgh, working with the Gartnavel General Hospital in Glasgow.

Prof Dhillon said: "This study is the first of its kind anywhere in the world and it is exciting to be involved in such groundbreaking work.

"I probably see two or three new cases of corneal disease every month. On a larger scale, it's a significant problem."

The trial will hope to emulate the success of a similar study in the US in September last year.

In trials at the University of Pennsylvania, subjects with inherited blindness experienced dramatic improvements in vision after a corrective gene was injected into the eye.

Copyright 2009, BBC

Saliva Test Could Monitor Type 2 Diabetes

TUESDAY, Jan. 20 (HealthDay News) -- Scientists say they are on the verge of developing a saliva test for monitoring type 2 diabetes, which might someday replace invasive blood tests.

For the first time, researchers from Oregon and India have identified proteins in saliva that appear more frequently in people with diabetes than in non-diabetics. Using these proteins, they are working to develop a test to monitor and perhaps diagnose the condition.

However, Dr. Umesh Masharani, an associate clinical professor of medicine at the University of California, San Francisco, doesn't think this approach is going to replace current blood tests any time soon.

"I think this is an interesting and novel approach," Masharani said. "I do not think this approach will be used in the diagnosis or treatment of diabetes any time in the near future. It is interesting, I think, for research studies in diabetes."

The report was published in the Jan. 2 issue of the Journal of Proteome Research.

For the study, Paturi V. Rao, from the departments of Endocrinology and Metabolism and Medicine at Nizam's Institute of Medical Sciences University in Hyderabad, India, and colleagues analyzed saliva samples from people with and without type 2 diabetes. Their goal was to find proteins associated with the blood sugar disease.

The researchers found 65 proteins that occurred twice as frequently in the people with diabetes than in those without the condition.

Using these proteins, Rao's team hopes to develop a noninvasive test for diabetes screening, detection and monitoring.

Rao's group thinks the pain involved with current diabetes monitoring causes many diabetics to be lax in monitoring their condition. A noninvasive test could make it easier and less painful for patients to keep track of their blood sugar levels.

"As recent studies have shown that early and multi-factorial intervention in diabetes prevents cardiovascular complications and mortality, advances in understanding molecular aspects of preclinical diabetes will further facilitate accurate diagnosis and early intervention," the authors wrote.

Diabetes expert Dr. Charles F. Burant, a professor of internal medicine at the University of Michigan, isn't convinced that a test using proteins in saliva is needed.

"I think it has minimal clinical impact," Burant said. "To be a valid biomarker, a test has to be sensitive and specific. We don't know the value of either for any of the proteins at the present time."

The biggest question is why this is needed, Burant noted. "Diabetes and prediabetes have a valid biomarker -- glucose -- that is the measure of the disease state. Thus, this is interesting biochemistry and raises questions why these changes occur, but the clinical utility is unclear."

More information

For more about type 2 diabetes, visit the American Diabetes Association.

SOURCES: Umesh Masharani, M.D., associate clinical professor, medicine, University of California, San Francisco; Charles F. Burant, M.D., Ph.D., professor, internal medicine, University of Michigan, Ann Arbor; Jan. 2, 2009, Journal of Proteome Research

Last Updated: Jan. 20, 2009

Copyright © 2009 ScoutNews, LLC. All rights reserved.

Paintballs can cause 'devastating' eye injuries.

CTV.ca News Staff

Paintball looks like a great indoor activity for kids in winter, but the American Journal of Ophthalmology is warning that the sport can cause severe and "visually devastating" eye injuries, especially when used in unsupervised settings.

Players gather in teams to shoot the opposition with paint pellets that fly up to speeds of 300 km per hour. The challenge however, is not in shooting the pellets, but dodging them.

Many paintball facilities require customers to wear protective eye goggles. Most of the injuries studied by medical professionals involve injuries at home or in unsupervised and unofficial settings.

"Eye injuries secondary to high-velocity paintballs can cause tremendous damage to vital ocular structures often requiring extensive surgical intervention," Dr. Kyle J. Alliman of Bascom Palmer Eye Institute said in a news release. "Unfortunately, visual loss is often permanent."

Alliman and colleagues at the institute, in Miami, analyzed the characteristics and outcomes of 36 patients treated for paintball injuries between 1998 and 2005. The patients were mainly young men, average age 21 years.

The injuries were often quite severe:

• rupture of the eyeball in 28 per cent of patients
• detached retina in 19 per cent
• surgery was required in 81 per cent of patients
• removal of the eye (enucleation) in 22 per cent

Even when the eye was saved, many patients had permanent visual loss, the study found. Overall, near-normal vision (20/40 or better) was restored in only 36 per cent of eyes.

All of the patients were injured when using paintballs in a "non-recreational, uncontrolled setting," according to Alliman. None of the injuries occurred in formal, sponsored event. In all but one of the 36 cases, the patient was not wearing any type of eye protection when the injury occurred.

This study, published Thursday in the American Journal of Ophthalmology, follows a recommendation last year from the Montreal Children's Hospital that paintball arenas to refuse entry to children under the age of 16.

A study published in the Canadian Medical Association Journal in the late 1980s found 17 people out of 44 injured by paintball pellets became legally blind. Thirteen became visually impaired and only 14 regained normal vision.

They also found that most of the injuries happen at home and not at arenas where goggles are mandatory.

A later study published by U.S. journal, Pediatrics, estimated that more than 40 per cent of paintball injuries happened to children.

Research suggests cell-phone use does not appear to increase risk of uveal melanoma.

For those of you who have wondered...

By Caroline Wilbert
WebMD Health News

Reviewed by Louise Chang, MD

Jan. 13, 2009 -- Talking on your cell phone does not increase your chances of getting melanoma of the eye, according to a new study.

The findings override an earlier report that linked the use of mobile phones with this type of cancer, according to researchers. The latest study is published in the Jan. 13 online issue of the Journal of the National Cancer Institute.

Andreas Stang, MD, of the Martin-Luther-University of Halle-Wittenberg in Germany, and colleagues, examined the association between phone use and risk of uveal melanoma in 459 patients with uveal melanoma compared to people without uveal melanoma.

Past research has shown there is no link between exposure to radio waves, including those on a cell phone, and DNA changes that can lead to cancer, according to background information cited by the study. However, studies addressing the possible link between use of cell phones and cancer continue to be performed.

This most recent study overrides an earlier study by the researchers involving only 118 participants with uveal melanoma. For that study, the exposure was only assessed if it was in the workplace. The findings at the time seemed to suggest a greater risk of uveal melanoma in people who used cell phones more often at work.

"In conclusion, we observed no overall increased risk of uveal melanoma among regular mobile phone users or users of radio sets in Germany, where digital mobile phone technology was introduced in the early 1990s," the researchers write.

© 2009 WebMD, LLC. All rights reserved.

Researchers identify protein that may prolong lives of retinal cells

THURSDAY, Jan. 8 (HealthDay News) -- Researchers working with mice have identified a protein that appears to prolong the lives of retinal cells in both healthy and diseased eyes.

The discovery could one day lead to treatments that would prevent blindness among people genetically predisposed to develop retinal disease, the scientists said.

The protein, known as histone deacetylase 4 (HDAC4), is naturally produced by both mice and humans and is typically involved in the regulation of bone and muscle development.

Reducing the amount of HDAC4 to below-normal levels appears to lead to premature photoreceptor cell death in healthy eyes, the study revealed. In contrast, increasing quantities of this protein to above-normal levels appears to protect the lifespan of these critical vision cells -- both in healthy mouse eyes and in those mice suffering from a genetic flaw, also present in humans, that gives rise to degenerative retinal disease.

The finding -- if replicated in people -- could ultimately lead to new interventions to prevent such disease-driven blindness, or even to the development of methods to restore lost sight to diseased retinas.

"There are some inherited genetic defects that lead to the death of the two types of photoreceptor cells in the eye that capture light, first directly killing the rod cells and then the cone cells which depend on rod cell survival," explained study author Bo Chen, a postdoctoral research fellow with the Howard Hughes Medical Institute at Harvard Medical School in Boston. "So, this mutation eventually leads to complete blindness."

"But what we found," Chen noted, "is that we could actually promote the survival of these genetically affected photoreceptors by introducing more of this particular protein, even though the photoreceptors themselves continue to remain genetically defective."

Chen and his colleagues report their findings in the Jan. 9 issue of Science.

The findings are based solely on a series of neural cell experiments, focused on the retinal health of live mice, that were designed to assess the impact of both under-expression and overexpression of the HDAC4 protein.

Subsequent lab work led the researchers to determine that in sufficient quantities the protein indeed displays a protective effect against eye cell death and thereby has an "essential role in neuronal survival," they wrote.

Yet despite expressing enthusiasm for his current work, Chen emphasized the ongoing nature of the effort.

"Even though the genetics are the same in mice and humans, at this stage it's really very experimental," he stressed. "And much more work needs to be done before we know this will be efficacious in humans."

Nevertheless, Dr. Robert Cykiert, a clinical associate professor of ophthalmology at New York University Langone Medical Center in New York City, described the current work as an "impressive" effort.

"Clearly a lot of people go blind from retinal diseases," he said, noting that glaucoma and macular degeneration are two serious conditions that result from retinal cell death. "And this protein they worked with appears to be what we call neuro-protective, in that it has protective benefits on both the photoreceptor layer that gets damaged in macular degeneration as well as on the ganglion cell layer which is damaged by glaucoma. So this finding could actually turn out to be a major accomplishment, affecting a lot of patients down the road."

However, Rando Allikmets, an associate professor of ophthalmology, pathology and cell biology at Columbia University in New York City, took Chen's cue in cautioning that the true measure of the current work awaits human clinical trials.

"It's a very good study, an interesting observation and a very encouraging finding that will definitely lead to an investigation of this pathway for possible therapeutic targets," he said. "But the problem is that they have identified a protein involved with very basic functions -- including muscle development and bone growth -- so it's very difficult to predict if what they did in mice can be done in humans at all and, even if it can, if it will work in the same way."

Cykiert agreed.

"Of course, it's a mouse study," he acknowledged. "So you certainly don't know if what they've found will be reproduced in patients. And in any case, it would take 10 years to develop any drugs from this that might benefit people. So, yes, it's just a first step."

More information

For more on the causes of blindness, visit the World Health Organization.

SOURCES: Bo Chen, Ph.D., postdoctoral research fellow, Howard Hughes Medical Institute, Harvard Medical School, Boston; Robert Cykiert, M.D., ophthalmologist and clinical associate professor, ophthalmology, New York University Langone Medical Center, New York City; Rando Allikmets, Ph.D., associate professor, ophthalmology, pathology and cell biology, Columbia University, New York City; Jan. 9, 2009, Science

Last Updated: Jan. 08, 2009

Copyright © 2009 ScoutNews, LLC. All rights reserved.

Coping with Decreasing Vision

ROCHESTER, Ill., Jan. 6 (UPI) -- A U.S. health newsletter suggests there are ways to help compensate for fading vision.

If eyesight fades over time because of aging or an eye disease, the Mayo Clinic Health Letter suggests:

-- Reducing differences in brightness. Equalize indoor and outdoor light sources by leaving some house lights on during bright sunny days.

-- Reducing glare by covering shiny surfaces, such as a polished table, with a cloth. Dark-colored place mats can help at mealtime. Use furnishings with a flat or matte finish.

-- Lighting up dark spots. Install lighting in dark areas, such as inside closets. Keep a pocket flashlight handy for dark areas.

-- Using bright, direct lighting. Position an adjustable lamp about 4 to 8 inches from reading material or a close-up task. Keep the lamp slightly to one side to reduce glare. If possible, position the light over the shoulder on the side of the better-seeing eye.

-- Taking advantage of natural light by positioning windows to the side or behind tasks.

-- Using a dark background when reading to reduce glare. A piece of dark construction paper can cover areas of text not being read.

© 2009 United Press International, Inc. All Rights Reserved.