Genetic Link To Age-related Cataracts Uncovered

Researchers from Case Western Reserve University have identified the EphA2 gene, which is associated with the formation of age-related cataract, a leading cause of blindness.



The gene encodes an enzyme that plays a role in the repair of damaged proteins in the eye. Expression of the EphA2 gene decreases with age, which means damaged proteins can clump together and cause the eye lens to become cloudy, resulting in obscured vision, according to the study in the July 31 issue of the journal PLoS Genetics

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BLOOD STEM CELLS PROGRAMED TO BECOME VISION CELLS

Florida researchers were able to program bone marrow stem cells to repair damaged retinas in mice, suggesting a potential treatment for one of the most common causes of vision loss in older people.

The success in repairing a damaged layer of retinal cells in mice implies that blood stem cells taken from bone marrow can be programmed to restore a variety of cells and tissues, including ones involved in cardiovascular disorders such as atherosclerosis and coronary artery disease.

In a paper slated to appear in the September issue of the journal Molecular Therapy, scientists describe how they used a virus carrying a gene that gently pushed cultured adult stem cells from mice toward a fate as retinal cells. Only after the stem cells were reintroduced into the mice did they completely transform into the desired type of vision cells, apparently taking environmental cues from the damaged retinas.

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Ozurdex Implant Approved for Macular Edema

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An injectable eye implant approved by the U.S. Food and Drug Administration Thursday is the first product sanctioned to treat the eye disorder macular edema when it is caused by blockage of the retinal vein.

The Ozurdex eye implant treats macular edema by delivering a high concentration of the corticosteroid dexamethasone.

Macular edema occurs when the eye's macula -- a part of the retina -- swells because of fluid accumulation from leaking or blocked retinal veins. In a news release, device maker Allergan, Inc. said retinal vein occlusion is a significant cause of vision loss and the second most common disease of the retinal veins, behind diabetic retinopathy.

The implant, which is biodegradable, was evaluated in a pair of clinical studies involving about 1,300 people.

The treatment, to be injected in a physician's office, is expected to be available later this year

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ALLERGAN RECEIVES FDA APPROVAL FOR ACUVAIL

The FDA has approved Allergan Inc.'s Acuvail (ketorolac tromethamine ophthalmic solution) 0.45%, an advanced, preservative-free formulation of the NSAID ketorolac indicated for the treatment of pain and inflammation following cataract surgery. According to the company, Acuvail is formulated at pH 6.8, enabling deionized drug delivery on the corneal surface, and contains carboxymethylcellulose, which enables the drug to adhere to the ocular surface and enhances patient comfort. The company expects Acuvail to be available to physicians and patients in the United States in September 2009.

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Ocular Surface Temperature and Lipid Layer Thickness

The aim of this study was to establish the relationship between ocular surface temperature (OST), tear film stability as assessed by noninvasive tear break-up time (NIBUT) and subjective evaluation of the lipid layer thickness in a young, asymptomatic, sample group (n=29). NIBUT and tear lipid layer structure were evaluated through a slit-lamp mounted Tearscope Plus. A self-calibrating infrared thermography camera was used to record two OST values (one immediately post-blink and one immediately pre the subsequent blink).

The most common lipid layer pattern observed was the amorphous pattern (48.3%). Differences between post- and pre-blink OST values were observed. Significant differences of pre-blink OST values were observed between the closed marmoreal group with that from the amorphous and flow groups. There were no differences of NIBUT values between each lipid layer thickness.

A non-significant tendency for higher OST in eyes with increased NIBUT was observed. This study suggests that higher OST values could be associated with thicker tear lipid layer in normal subjects. The lack of significant results in relation with tear film stability may be due to only normal subjects were included.

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NASA Study of Cataract in Astronauts

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The NASA Study of Cataract in Astronauts (NASCA) is a 5-year longitudinal study of the effect of space radiation exposure on the severity/progression of nuclear, cortical and posterior subcapsular (PSC) lens opacities. Participants include 171 consenting astronauts who flew at least one mission in space and a comparison group made up of three components: (a) 53 astronauts who had not flown in space, (b) 95 military aircrew personnel and (c) 99 non-aircrew ground-based comparison subjects. Continuous measures of nuclear, cortical and PSC lens opacities were derived from Nidek EAS 1000 digitized images. Age, demographics, general health, nutritional intake and solar ocular exposure were measured at baseline. Astronauts who flew at least one mission were matched to comparison subjects using propensity scores based on demographic characteristics and medical history stratified by gender and smoking (ever/never).

The cross-sectional data for matched subjects were analyzed by fitting customized non-normal regression models to examine the effect of space radiation on each measure of opacity. The variability and median of cortical cataracts were significantly higher for exposed astronauts than for non-exposed astronauts and comparison subjects with similar ages. Galactic cosmic space radiation (GCR) may be linked to increased PSC area and the number of PSC centers. Within the astronaut group, PSC size was greater in subjects with higher space radiation doses. No association was found between space radiation and nuclear cataracts.

Cross-sectional data analysis revealed a small deleterious effect of space radiation for cortical cataracts and possibly for PSC cataracts. These results suggest increased cataract risks at smaller radiation doses than have been reported previously.

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Increase in ocular melanoma rates to use of tanning booths.

NBC Nightly News reported about the tanning bed industry. "While the risk of skin cancer is well known, [a] dire warning...compared the effects to cigarette smoking and arsenic. Chief medical editor Nancy Snyderman, MD, explained that according to the World Health Organization, an exponential increase in skin cancer can be linked to the use of indoor sun and tanning booths. For people who start using the booths before the age of 30, their risk goes up 75 percent."
        The Tampa Tribune reports that the declaration by the WHO's International Agency for Research on Cancer (IARC) that tanning booths emitting ultraviolet radiation are carcinogenic simply echoes what dermatologists say they've suspected for years. The declaration, published in the August issue of The Lancet Oncology, ranked tanning beds right up there with tobacco smoke and mustard gas. Dermatologist Neil Alan Fenske, MD, of the University of South Florida, pointed out that for some time, tanning beds that use ultraviolet rays were suspected of causing skin cancer. He stated that the members of the American Academy of Dermatology have been fighting this battle for a number of years, adding that patients who have received abundant amounts of light via tanning beds have developed extraordinary numbers of skin cancers.
        The Detroit Free Press reports that IARC made its announcement after finding enough evidence in people and mice that UVA and UVB rays damage skin-cell DNA, sometimes in cancer-blocking genes. The damage may result in three types of skin cancer: the less dangerous basal and squamous cell skin cancers and melanoma, explained dermatologist Darius Mehregan, MD, of Wayne State University. The Free Press notes that the American Academy of Dermatology had no comment on the international decree, and calls to the Indoor Tanning Association were not immediately returned.
        According to MedPage Today , citing evidence from case-control studies and a meta-analysis, the IARC monograph working group 'raised the classification of the use of UV-emitting tanning devices to Group 1, 'carcinogenic to humans.' In addition, the working group also cited case-control studies showing 'consistent evidence of an association between the use of UV-emitting tanning devices and ocular melanoma.' In fact, the IARC reclassified all forms of ultraviolet radiation as a single carcinogenic entity. Historically, mutations caused by exposure solar radiation had been attributed to UVB, but the same mutation was identified in UVA-induced skin tumors in mice. In its update, the IARC moved UV radiation as a whole into the highest-risk category, eliminating distinctions between UVA, UVB, and UVC.
        The Philadelphia Inquirer quoted John Overstreet, executive director of the Indoor Tanning Association, as saying, Because tanning beds produce the same UV light as the sun, overexposure and abuse of our product -- just like overexposure to sunlight -- is associated with an increased risk for some types of skin cancer.
        USA Today faults industry promotion of questionable health benefits of tanning. USA Today editorializes, Despite mounting evidence linking tanning beds and cancer, the Indoor Tanning Association, which represents the industry, has shamelessly promoted questionable health benefits instead. In fact, its most recent campaign has been to convince people that tanning beds are beneficial because they are a source of Vitamin D. A few years ago, the tanning industry encouraged now-disproven claims that the mainly UVA ultra-violet rays emitted by sun beds do not do the same damage as the sun's. In 2008, its director termed assertions of a link between tanning beds and melanoma 'irresponsible.' USA Today argues, It's the industry that appears irresponsible, much as Big Tobacco once was as it tried to refute science. The paper calls for better education about tanning dangers, along with stronger warnings and action against misleading health claims.

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River blindness can be stopped by drugs: WHO

River blindness may be eradicated through long-term ivermectin use.



New studies, published Tuesday in the journal PLoS Neglected Tropical Diseases, suggest river blindness can be wiped out with a long enough course of ivermectin. The World Health Organization (WHO) said the studies demonstrated that treatment with the drug ivermectin stopped further infections and transmission of the disease in three areas of Africa in Mali and Senegal.

The drug ivermectin, developed in 1987 by Merck, kills the larvae of the parasite that causes the disease, but not the adult worms, so scientists thought treatments were needed every six months or year to keep it under control. Researchers found, however, that after 15 to 17 years of regular treatment, only a few infections remained after treatment was stopped in...three test areas, leading them to conclude that river blindness can be wiped out with a long enough course of ivermectin. AFP notes that main funding for the studies came from the Bill & Melinda Gates Foundation.

BBC News reports that currently, at least 37 million people are infected with the disease, which causes sufferers to lose their sight and also to develop painful skin complaints. River blindness is endemic in many parts of Africa, primarily in poor, rural communities. The disease is caused by a parasite that is transmitted to people through the bite of the black fly. The worms spread through the body and when they eventually die, our immune system reacts fiercely. That reaction destroys living tissue -- especially the eye. While doctors have known for years that drugs can control the disease, they now believe it can be eliminated.

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Half a brain girl recovers vision

According to research published in the Proceedings of the National Academy of Sciences, researchers from the UK's University of Glasgow say they have solved the mystery of how a girl with half a brain has near perfect vision in one eye.

The 10-year-old girl was born missing the right side of her brain, whose job it is to map the left field of vision. Magnetic resonance imaging scans showed that the girl's brain rewired itself during development when she was still  in utero. In spite of having some seizures as a toddler, which were successfully treated, and slight weakness on her left side, the girl has had a normal medical history, attending school and taking part in regular activities. Amazingly, her left and right field vision is almost perfect in one eye.

Dr Lars Muckli, of the university's Centre for Cognitive Neuroimaging, said: "The brain has amazing plasticity but we were quite astonished to see just how well the single hemisphere of the brain in this girl has adapted to compensate for the missing half.

"Despite lacking one hemisphere, the girl has normal psychological function and is perfectly capable of living a normal and fulfilling life. She is witty, charming and intelligent."

Scans revealed that retinal nerve fibers carrying visual information from the back of the eye which should have gone to the right hemisphere of the brain diverted to the left.

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Intra-oral device helps blinded Marine to discern shapes.

Washington Post reports that a special 'lollipop,' a device that uses the tongue to stimulate the visual cortex and send sensory information to the brain, is helping Marine Cpl. Mike Jernigan, who lost both of his eyes in a roadside bomb attack in Iraq, to discern shapes.

The intra-oral device, or IOD...is an inch-square grid with 625 small round metal pieces that is connected by a wire to a small camera mounted on a pair of sunglasses and to a hand-held controller about the size of a BlackBerry. Images are sent by the camera to the IOD, which transmits a low-voltage pulse to Jernigan's tongue. With training, Jernigan has learned to translate that pulse into pictures.

Optometrist Amy Nau, OD, who is researching the effectiveness of the device at the University of Pittsburgh, explained, It's kind of like Braille that you use with your fingers. Dr. Nau added, Instead of symbols, it's a picture, and instead of your fingertips, it's your tongue. The IOD, called the BrainPort vision device...is manufactured by Wicab.

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Glaucoma biggest cause of blindness in New Zealand

Glaucoma NZ chairwoman Helen Danesh-Meyer has highlighted the biggest cause of blindness in New Zealand. It is estimated that 68,000 people have glaucoma in New Zealand. The Dominion Post has an excellent article highlighting this issue.

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Glaucoma surgeries up while Medicare reimbursement down

According to a study published in the July issue of the Archives of Ophthalmology, the number of glaucoma surgeries is on the rise, but Medicare reimbursement for the procedures has been decreasing.

For the study, researchers from Exponent, Alcon Research, and the Bloomberg School of Public Health analyzed Part B Medicare data for 100,000 beneficiaries from 1997 to 2006. The team found that from 1997 to 2001, there was an overall decrease in both the number of procedures and the amount of annual payments, but there was an increase in the number of procedures in the following years, reaching a total of 414,980 in 2006. The investigators attributed the increase to advancements in technology and a change in calculating the global period for reimbursement purposes.

The authors also noted that payments for trabeculectomies decreased over time, while annual payments for newer procedures, such as cyclophotocoagulation and shunt-related procedures, have increased.

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A new paradigm for understanding glaucoma has emerged

Glaucoma isn't simply an eye disease, experts now say, but rather a degenerative nerve disorder, not unlike Alzheimer's or Parkinson's disease.

While researchers still recognize high pressure within the eye as a leading risk factor for glaucoma, it is becoming clear that the condition begins with injury to the optic nerve as it exits the back of the eye. The damage then spreads, moving from one nerve cell to adjoining nerve cells.

Neeru Gupta, MD, PhD, of the University of Toronto, explained, In glaucoma, we've shown that when your retinal ganglion cells are sick, the long axons that project from the eye into the brain are also affected, resulting in changes that we can detect in the vision center of the brain. This phenomenon, called transynaptic damage, occurs in Alzheimer's and Parkinson's disease, as well.

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About 200,000 new cases of advanced, age-related macular degeneration (AMD) are identified each year in the United States, many older Americans with more severe or "wet" forms of AMD endured inevitable, gradual loss of central vision.
Lucentis in clinical trials has been shown to stop and, in many cases, reverse at least some vision loss in most people with advanced AMD. Another drug closely related to Lucentis, known as Avastin (bevacizumab), also has been shown to be a highly effective and far cheaper alternative for lower-income individuals with advanced AMD.
The problem is that Avastin is FDA-approved only for treatment of colon and other cancers, but not for macular degeneration. As an alternative, many eye doctors have been using Avastin as an "off-label" treatment.
Pharmaceutical companies are driven by financial intersts, while physicians with patient care. Here is an excellent article that summarizes it.

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Does your employer care about your vision

Charlotte, NC has seen many things change over the course of the last years financial crisis. Both financial institutions Bank of America and Wachovia (now, Wells Fargo) have seen major shifts in how they do business.

From my perspective as an optometrist, the most notable has been the change in vision insurance plans especially for BofA. They moved from VSP considered a better partner to private practice optometrist to Eyemed (who also run the chain Lenscrafters).

The question that's raised is: how much shall companies bear for the employees eye care?.

It surely is no secret that if your vision is impaired, it affects practically every sphere of your life. Yet, we find that one place most organizations cut back is in vision and related service. It enrages me to see some plans that restrict eye exams to 24 months! Especially when they are kids! I spend considerable amount of time explaining to parents the need for annual eye exams.
Recently, a study of the eye care policies of the UK's top 250 companies revealed considerable confusion among employers over their responsibilities for the eye care of their employees. The results also showed that 59 per cent of the UK's leading 250 companies believe that they are only required to make a contribution towards the cost of glasses, while a further 20 per cent believed contributions are entirely voluntary.

I hope there is an independent study of the top 250 companies in the US, where the Human Resource officers are surveyed about their responsibilities to employees vision.

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Laser treatment may help reverse effects of dry AMD

A ground-breaking laser treatment may help reverse the effects of age-related macular degeneration (AMD). In early proof-of-concept trials involving about 50 people, the laser technique, which was developed by pioneering eye expert Professor John Marshall of King's College London, appeared to return the back of the eye to its youthful state.

In the technique, a painless 'short pulse' laser boosts the release of the enzymes to clean away natural waste materials, but without damaging the cells that enable vision. The researchers now plan further studies in patients already suffering from AMD in one eye with the aim of saving the sight in their better eye for as long as possible.

Professor Marshall said that he hoped the treatment would be available within two to five years. There is currently no treatment for the most common form of AMD -- known as 'dry' AMD -- which the new laser technique could prevent.

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Recent estimates by the World Health Organization (WHO) calculate at least 171 million people worldwide suffer from diabetes and expect this figure to more than double, to reach 366 million, by 2030

According to Sanofi-Aventis SA, its long-acting Lantus [insulin glargine] drug didn't increase the risk of blindness for diabetics compared to an older type of insulin in a five-year study of more than 1,000 patients. In addition, there was...no 'observable trend' showing a difference in the risk of serious side effects including cancer, the drugmaker said in a statement.

"This 5-year study is the longest randomized controlled study with insulin glargine versus NPH human insulin," said lead investigator Julio Rosenstock, MD, Director of the Dallas Diabetes and Endocrine Center at Medical City and also Clinical Professor of Medicine, University of Texas Southwestern Medical Schoo.

The study results were published in the online edition of the Diabetologia medical journal.

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Lucentis met late-stage trial goal in patients with macular edema due to BRVO

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Genentech, Inc. announced that its macular degeneration drug Lucentis [ranibizumab] met its goal in a late stage trial, improving the vision of patients with macular edema due to branch retinal vein occlusion.

Currently, Lucentis is approved to treat neurovascular, or 'wet,' age-related macular degeneration. Genentech is now trying to get the drug approved for macular edema due to branch retinal vein occlusion, a condition in which the macula, or central part of the retina, swells because fluid leaks or builds up.

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Light-sensing worms provide a new tool for the study of vision

A team from the University in Michigan, led by Shawn Xu, has discovered that tiny worms can sense light.

They discovered that the chemical reactions used by the C. elegans ( a 1mm sized worm which is one of the most commonly used model animals in genetic research) are rather similar to the ones in humans. This discovery means that from now on the worm can be used for the research of building blocks of human vision, as well as how disrupting the phototransduction pathway can lead to eye disease.

This discovery may lead to further breakthroughs in the research of vision, helping researchers understand the basis of human vision diseases and promote the understanding of the evolutionary development of eyes in various species.

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Experiment seeks to head off Type 1 diabetes

Researchers at Children's Hospital of Pittsburgh are hoping to control type 1 diabetes by curbing the rogue immune cells that cause it, before patients become completely dependent on daily insulin injections tosurvive.

About 3 million Americans have Type 1 diabetes, where the body mistakenly attacks and destroys cells in the pancreas that produce insulin, the hormone crucial to converting blood sugar to energy.

This novel vaccine -- made from patients' own blood blocks the '911 call' that dendritic cells send to direct T cells to the pancreas. Just altering three communication molecules on their surface basically confuses and paralyzes the T cells. In mice and monkeys, the reprogrammed cells ended the vicious cycle of a pancreas attack that in turn attracts more T cells to attack again.

In human trials, the team has used donated blood to filter out immature dendritic cells and then reprogram them. Animal experiments have shown that after the cells have been re-injected just inside the skin over the pancreas...the cells somehow find their way back to that organ to start working.

Two competing teams - MacroGenics Inc. and Eli Lilly, and Tolerx Inc. and GlaxoSmithKline - have advanced tests under way

Currently, 15 adult diabetics [are] being injected to make sure there are no unexpected side effects before researchers test if reprogrammed cells might really protect children's pancreas cells

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