According to a study published in the January issue of the Archives of Ophthalmology, high caloric and sodium intake appear to be associated with the progression of diabetic retinopathy (DR) among African American patients with type 1 diabetes.

In a study population of 469 individuals at risk for the progression of DR, researchers found that baseline total caloric intake was significantly associated with a six-year incidence of vision-threatening Diabetic Retinopathy (either proliferative DR or macular edema [ME]) and of severe hard exudates, while high sodium intake at baseline was a significant, independent risk factor for six-year incidence of ME.

Limitations of this study include single measurement of nutrient intake, failure to adjust for multiple comparisons, and lack of generalizability to other populations.

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Researchers question causes of myopia

On its "Morning Edition" program, NPR reports on the search for the causes of myopia. Epidemiologist Susan Vitale, of the National Eye Institute, explained that a study she coauthored in December's Archives of Ophthalmology found about a 66 percent increase in myopia over 30 years.


NPR notes that near-work the things you do close up with your eyes, like reading or watching television, has been suspected as contributing to nearsightedness, but a study by researchers at the College of Optometry at the Ohio State University found that near-work had no influence. They did discover, however, that the amount of outdoor activity a child had an influence the development of myopia.

Now, researchers are studying whether outdoor light somehow changes the way the eye grows

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The New York Times reported that the decline of written language has become a reality for only the blind, as fewer and fewer visually impaired people learn Braille, many preferring instead to rely upon synthetic voice technology and computer-screen-reading software.

In fact, a report released last year by the National Federation of the Blind, an advocacy group with 50,000 members, said that less than 10 percent of the 1.3 million legally blind Americans read Braille. The report found that while approximately half of all blind children learned Braille in the 1950s, today that number is as low as one in 10.

Increased number of blind children born with additional physical or mental handicaps, often the result of premature birth. And a large percentage of these students were partly sighted. There is a wonderful article explaining this so well in the Arizona Republic June 1, 2006 . The reporter interviewed Arielle Silverman President of the Arizona Association of Blind Students.

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Statin use is not associated with risk of developing advanced, age-related macular degeneration (AMD), according to a study published in the Dec. issue of Ophthalmology.

In a study of 744 patients, researchers from the University of Pennsylvania found that among patients who had bilateral large drusen, use of the cholesterol-lowering medications was not associated with a higher or lower risk of progressing to advanced disease.

At baseline, all patients were at risk for advanced AMD but had not yet progressed to that stage.

At the end of the study, 39.8% of the participants reported using statins; about two-thirds starting taking the drugs during the trial.

The investigators theorized, however, that a protective effect may have been obscured because patients who are taking statins for cardiovascular disease are also at high risk for developing AMD.

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AMD treatment with NeoVista system

Wet AMD occurs when abnormal blood vessels behind the retina start to grow under the macula, where they leak blood and fluid, causing scar tissue to form and vision to become impaired. With wet AMD, vision loss may occur faster and be more noticeable than with dry AMD. The longer the abnormal vessels leak or grow, the more detail vision will be lost. The earlier wet AMD is diagnosed, the better the patients' chance of preserving some or much of their central vision.

The first European patients have been treated for wet age-related macular degeneration with NeoVista's Vidion ANV Therapy System, an epimacular brachytherapy device that delivers a single dose of therapeutic radiation, the manufacturer announced in a press release.

Stanislao Rizzo, MD, of S. Chiara Hospital, Pisa, Italy, treated the initial group of patients with the Vidion ANV Therapy System. Unlike previous radiation therapies for wet AMD, NeoVista's innovative device delivers the peak dose of strontium-90 beta ionizing radiation directly to the lesion minimizing exposure to the surrounding tissue. The minimally invasive procedure utilizes a device similar in size to a needle, to deliver a highly targeted dose of radiation directly to the area of the retina affected by wet AMD. Importantly for patients, the systemic radiation exposure is minimal, as the effective dose to the entire body from NeoVista's epimacular brachytherapy device is less then a routine chest x-ray.

The Vidion system is undergoing phase 3 clinical trials for U.S. Food and Drug Administration marketing approval. The device proved safe and effective in preliminary clinical trials, the release said.

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Blood test to identify retinopathy in Type 1 Diabetics

A routine blood test may identify juvenile-onset diabetic patients at heightened risk for proliferative retinopathy.

In a multivariate analysis of data on 426 people followed over 18 years from Pittsburgh Epidemiology of Diabetes Complications Study, researchers found that each increment of 1 g/dL in hemoglobin was associated with a linear 29% increase in risk for retinopathy in men with type 1 diabetes (95% CI 8% to 54%), and a quadratic 10% risk increase in women (95% CI 0% to 20%).

Notably, only diastolic pressure and glycated hemoglobin were predictive of retinopathy in multivariate analysis for both sexes, while systolic pressure predicted retinopathy in women (HR 1.03 per mm Hg), but not in men.

The researchers noted that the difference in the nature of the relationship between hemoglobin and retinopathy risk between sexes -- linear in men, quadratic in women -- may just be a statistical fluke, arising from the small number of men with hemoglobin levels below 13.5 g/dL.

A U-shaped relationship, indicating increased retinopathy risk for both low and high levels of hemoglobin, is likely to apply to both sexes, they said

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Combined drug to treat nasal and ocular allergies

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A study published in the Annals of Allergy, Asthma, and Immunology and presented at an allergy conference, showed that the combination of azelastine (Astelin or Astepro) and fluticasone propionate (Flonase) gave significantly better nasal symptom relief than placebo or either drug alone.
Azelastine is an antihistamine and mast cell stabilizer that is also sold as eye drops for allergic conjunctivitis under another brand name. Fluticasone is a synthetic glucosteroid that is used as an anti-inflammatory.

Investigators enrolled 610 patients with moderate-to-severe allergic rhinitis, randomly assigning them to get either azelastine, fluticasone, the combination nasal spray, or a placebo nasal spray twice a day for two weeks. They discovered that the combination was significantly better than either drug alone or placebo at relieving nasal symptoms, but the two drugs delivered together -- a combination dubbed MP29-02 -- were not significantly better than either drug as monotherapy for ocular symptoms

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Role of dietary fat in AMD

MedPage Today reported that, according to a study published in the Archives of Ophthalmology, " fat-filled diet may put younger women at risk for future age-related macular degeneration (AMD).

After analyzing dietary fat intake measured in 1,787 women, researchers found that women younger than 75 with the highest total fat intake (about 43% of daily calories) had 70% higher odds of intermediate AMD than those in the lowest quintile (21% fat calories).

Notably, photographic assessment for AMD revealed that 4% of the women had intermediate disease -- defined by extensive drusen deposits on the retina or optic nerve head as well as pigmentary abnormalities.

But as in some prior studies, macular degeneration risk rose with omega-6 intake (OR 2.0 for high versus low quintiles, 95% CI 1.1 to 3.5) after adjustment for age, and other fat intakes. The same was true for younger and older women alike. Omega-6 may promote inflammation, "which is thought to contribute to retinal damage that may promote age-related macular degeneration," the researchers said.

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Researchers develop photochromic contact lenses

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MIT's Technology Review reports Jackie Ying, director of the Institute for Bioengineering and Nanotechnology in Singapore as having developed an UV-responsive, or photochromic, lenses that darken when exposed to ultraviolet light, protecting the eyes against the sun's damaging rays, and return to normal in UV's absence.

The lenses contain a novel polymer laced with an intricate network of nano-sized tunnels that can be filled with dyes. Early studies have demonstrated that the technology performs faster than the transition sunglasses on the market today. The investigators hope to have photochromic contact lenses commercially available within a year.

Nanotechnology refers to the manipulation of matter at the molecular level and is measured by a nanometre scale that is between one and 100 nanometres. A sheet of paper is about 100,000 nanometres thick.

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Cataract surgery may not speed progression of AMD

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According to a study published in the Nov. issue of the journal Archives of Ophthalmology, cataract surgery doesn't appear to speed the progression of age-related macular degeneration (AMD).

Investigators examined 71 eyes of patients with non-neovascular AMD before, and at one week and one year after they had cataract surgery. They discovered progression to neovascular AMD occurred in 4.6 percent of the eyes between one week and one year after cataract surgery, compared with three percent for cataract-free eyes.

Medscape reported that an accompanying editorial by Barbara E. K. Klein, MD, MPH pointed out that several reports have shown an association between cataract surgery and AMD since the late 1980s, and that the diversity of findings in no small part begins with differences in study design.

Nevertheless, discussing these inconsistencies will help patients and their doctors make a more informed decision about the risks for progression to early AMD and development of late AMD after cataract surgery

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HbA1c better predictor retinopathy than FPG in US population

According to a study published in Diabetes Care, glycated hemoglobin (HbA1c) is a better predictor of retinopathy prevalence in the general population than fasting plasma glucose (FPG). Diabetes is a disease that occurs when the pancreas does not secrete enough insulin or the body is unable to process it properly. Insulin is the hormone that regulates the level of sugar (glucose) in the blood. Diabetes can affect children and adults. Patients with diabetes are more likely to develop eye problems such as cataract or glaucoma., but the main threat to vision is its effect on the retina.

Researchers analyzed data from 1,066 people, including values for HbA1c, FPG, and 45 degree color digital retinal images. After using area under the receiver operator curve analysis...the team found that HbA1c was a significantly stronger discriminator of retinopathy than FPG.

While diabetic retinopathy, or more specifically its associated threshold FPG value of 7.0 mmol/l, has been used in diagnostic criteria for type 2 diabetes by the American Diabetes Association, this study confirms...that HbA1c levels could be a superior measure for predicting retinopathy risk to FPG and may be more appropriate for use in diagnosing type 2 diabetes, the authors said.

Cheng et al conclude: “While the HbA1c and FPG levels of 5.5% and 5.8 mmol/l provide start points at which retinopathy prevalence increases most precipitously, HbA1c appears to discriminate between the presence and absence of retinopathy at least as well as FPG and offers some advantages over FPG.”

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A novel, "dual optic" accommodating intraocular lens improved intermediate distance vision and contrast sensitivity under low light conditions compared with some multifocal lenses, researchers said.

The findings, reported in two studies from the same research group here at the American Academy of Ophthalmology meeting, suggest that the new generation of lens will hold functional advantages for patients undergoing cataract surgery.

First generation monofocal lenses were often used to create "bifocal" vision, with the lens in one eye set for distance vision and the other set for near objects. To overcome the poor depth perception this created, the next generation of multifocal lenses allowed both eyes simultaneously to focus on far or near objects for "more natural vision with depth perception.

Andrea Galvis, MD, of the Fundación Valle del Lili in Cali, Colombia compared three of these "premium" intraocular lenses with an experimental lens (Synchrony) designed with a dual optic to theoretically provide a more accommodative amplitude. The study included patients given the same lens in both eyes during different "eras" of lens implantation. For a functional, real life performance test of contrast sensitivity, patients were given a reading speed test under low-light conditions.

The difference was significant for Tecnis and Synchrony compared with ReZoom and ReSTOR at P<0.001.>

Synchrony had the highest contrast sensitivity of all the lenses.

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Vegetable intake during pregnancy may prevent diabetes in unborn child

USA Today reports that, according to experts, an increasing number of children are being diagnosed with both type 1 and type 2 diabetes. According to Ed Kraus, an associate professor at Chicago Kent Law School who works with the American Diabetes Association (ADA), many schools are...falling short in coping with these students, particularly since 30% of schools have a part-time nurse, and 25% have no nurse.

Now, the ADA has a Safe at School Campaign to help families and schools create support plans, useful because everyone from cafeteria workers and bus drivers to gym teachers and the principal should know about a child's medical condition and what to do in case of an emergency, endocrinologist Frederick Schwenk, MD, says.

Diabetes risk in children may be linked to mothers' vegetable intake during pregnancy. HealthDay reported that, according to a study published online in the journal Pediatric Diabetes, children born to mothers who ate plenty of vegetables during pregnancy are less likely to have type 1 diabetes.

This is the first study to show a link between vegetable intake during pregnancy and the risk of the child subsequently developing type 1 diabetes, but more studies of various kinds will be needed before we can say anything definitive,” says study author and clinical nutritionist Hilde Brekke from the Sahlgrenska Academy

Swedish researchers studied 6,000 five-year-olds and found that three percent either had fully developed type 1 diabetes or had elevated levels of antibodies that indicate a risk of developing the disease. The investigators found that the risk was twice as high in children whose mothers rarely ate vegetables during pregnancy, and was lowest among children whose mothers ate vegetables every day of their pregnancy.

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Femtosecond-pulse lasers appear promising for cataract surgery

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Femtosecond-pulse lasers similar to those used for LASIK may take over manual incision and phacoemulsification in cataract surgery.

Researchers from the Bascom Palmer Eye Institute said that femtosecond laser incisions achieved perfect diameter accuracy in 100% of cases, while only 10% of surgeons' manual cuts were within 0.25 mm error. Investigators compared 60 manual and 60 LenSx femtosecond laser cataract surgeries done at the same center, and found that laser capsulotomy size, shape, and reproducibility were all statistically significantly better than manual capsulotomy.

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The Wall Street Journal "Health Blog" reported that the Centers for Medicare & Medicaid Services (CMS) appears late yesterday to have changed its mind about reimbursement for small amounts of Avastin [bevacizumab], which physicians use to treat patients with age-related macular degeneration (AMD).

Avastin, which is similar to Lucentis [ranibizumab], is used off-label to manage AMD, but unlike Lucentis, which costs approximately $2,000 per injection, Avastin costs only about $30 per injection, making it considerably cheaper. Late yesterday, however, CMS announced without explanation that as of Jan. 1, it will reverse its Oct. 1 decision to reimburse Avastin at approximately $7 per dose, and will return to its previous higher reimbursement for the drug.

MedPage Today explained that even after CMS lowered its reimbursement for Avastin on Oct. 1, "reimbursement for Lucentis...remained unchanged at a whopping $2,039," thereby creating "a disincentive for using a drug that has been estimated to save Medicare $1.5 billion each year in treating macular degeneration alone.

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MedPage Today reported that, according to a study presented at an ophthalmology meeting, "intravitreal injections of vascular endothelial growth factor (VEGF) inhibitors can cause persistent hypertension in the eye after only one treatment," a complication affecting 3.45 percent of patients given bevacizumab (Avastin) or ranibizumab (Lucentis) for age-related macular degeneration (AMD).
After "retrospectively" looking at 116 wet AMD patients treated with either VEGF inhibitor at their tertiary referral center from 2006 through 2008, researchers found that four patients developed persistent ocular hypertension. However, the ocular hypertension usually responds to antiglaucoma medication, though it returns if the drops are discontinued, the investigators said.

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Field Defects early indication of Alzheimer's

Alzheimer’s disease is a brain disorder named for German physician Alois Alzheimer, who first described it in 1906. We know it
Is a progressive and fatal brain disease
Is the most common form of dementia
Has no current cure.
A standard eye exam technique can throw light on early detection of this condition. And that test is Visual Field.
One-sided defects, (also referred to as right or left partial homonymous hemianopsia) on visual field testing were a giveaway in 80% of cases with the visual variant of Alzheimer's disease, according to Pierre-Francois Kaeser, MD, and Francois-Xavier Borruat, MD, both of the Jules-Gonin Eye Hospital in Lausanne, Switzerland.

Although we know that there is no specific cure, the sooner patients are referred to a neurologist the better, since early diagnosis and treatment may result in a better end prognosis.

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Gene therapy may improve vision in Leber's congenital amaurosis

The CBS Evening News reported that there is good news for the more than 10 million Americans who suffer from some type of vision disorder. In an experimental gene therapy trial at the Children's Hospital of Philadelphia, researchers used DNA from a DNA bank to create a functioning gene that was missing in 12 patients who were legally blind. The gene was then injected into the eye with a thin needle, which created a missing protein inside the faulty retina, helping to restore vision.

The Los Angeles Times reported that the finding, published in the Lancet, suggests it may be possible to produce similar improvements in a much larger number of patients with retinitis pigmentosa and macular degeneration. The participants had Leber's congenital amaurosis, and were born with severely impaired vision, which typically deteriorates until patients "are totally blind."

The Wall Street Journal reports that although the treatment did not restore normal sight in any participants, there was some improvement in all of them. Six participants reported enough vision to no longer be considered legally blind, while four children achieved significant recovery of vision.

According to Katherine High, a gene therapy researcher at the University of Pennsylvania, all of the participants had mutations disabling a gene called RPE65 that produces a protein essential to vision, Bloomberg News reported. Study author Jean Bennett noted that patients improved on standard vision tests, such as reading eye charts, and their pupils had a much greater response when light was shined in their eyes after being treated.

The study showed that the youngest participant's treated eye became 10,000 times more sensitive to light, as measured by the pupil's ability to constrict, while the eyes of the adults became hundreds of times more sensitive, at best, thePhiladelphia Inquirer reported. And, although expectations for patients in their 20s were low, those patients "improved more than the researchers expected."

The authors noted that the visual recovery noted in the children confirms the hypothesis that efficacy will be improved if treatment is applied before retinal degeneration has progressed, HealthDay reported. While patients younger than 20 had larger visual field recoveries than older patients, the study also showed that pupillary response...improved in the injected eye of all 11 patients tested. BBC News, the UK's Telegraph, and AFP also covered the story.

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The New York Times that researchers from the Massachusetts Eye and Ear Infirmary, the VA Boston Healthcare System, and Cornell University have demonstrated retinal implants that they say will resist the jarring of daily use.

The implant contains a tiny array of electrodes whose tips slide into a snug berth just beneath the retina...and are held in place by natural suction. These electrodes prompt the remains of retinal circuits to transmit signals to the brain, allowing patients with retinitis pigmentosa, a disease that damages the rods and cones in the eye, and for macular degeneration, which also affects these photoreceptors, to detect light and dark and to find the edges of objects.

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Retinal changes may be associated with Alzheimer's

Neuroscientists at the University of California-Irvine have discovered that the retinas of laboratory mice, whose genes have been altered so they develop Alzheimer's disease, experience changes similar to those in the brains of humans who have the disease.
Alzheimer's, affects over 5 million people in the U.S. and is the leading cause of elderly dementia. Brain imaging techniques are useful, but retinal imaging could be less invasive, less expensive and easier to perform.
For a study appearing in the November issue of The American Journal of Pathology, UCI neuroscientist Zhiqun Tan and colleagues analyzed the retinas of Alzheimer's mice that had been treated with immunotherapy.
Specifically, in both the retinas and brains, there is an accumulation of amyloid plaque lesions, a hallmark of the disease in brain imaging tests. Researchers said that the findings will be crucial to developing retinal imaging technology that could help diagnose and treat people with Alzheimer's Disease.

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