April 21, 2008, 6:07 PM CT

Sharper imags: sports vision clinic

The standard eye chart only covers letters and numbers, but athletes need above average vision to track balls hurtling toward them at alarming speeds. To test those special skills, a University of Houston optometrist has founded the Sports Vision Performance Center, a facility where athletes perform while a strobe light is flashing, play tag with a board of lights and engage in other activities designed to improve their visual abilities.

The biggest problem that athletes face is not knowing they can potentially see much better than 20/20 vision, said Kevin Gee, a Fellow of the American Academy of Optometry and an assistant clinical professor with the UH College of Optometry. Gee opened the Sports Vision Performance Center in January to individual athletes and teams from various sports, and utilizes a range of tests to analyze what is called the visual system.

The visual system is more than just whats the smallest line on the chart you can see, Gee said. The visual system consists of a number of things, but specifically for sports, depth perception, color, speed and accuracy of movements and contrast sensitivity or the ability to detect an object off a background.

To assess these skills, Gee and his staff use instruments, such as a 3-D movie projected on a computer screen with shimmering objects that pop up to measure depth perception, a lighted batting test that can time up to one-thousandth of a second to gauge timing and accuracy, and a Dynavision board a vertical lighted peg board that determines reaction time, peripheral awareness and accuracy of movement......... Posted by: Mike      Read more         Source

April 17, 2008, 7:43 PM CT

MU researchers find clue to cataract formation

It is the No. 1 line-item cost of Medicare reimbursement and affects more than 20 million people in the United States. Cataracts, which can have devastating effects on the eye, affect 42 percent of the population between the ages of 70 and 80, and 68 percent of the population over the age of 80, as per the National Eye Institute. Now, a University of Missouri professor has identified an important step in how cataracts form. This discovery, published in a recent edition of The Journal of Biological Chemistry, could lead to a better therapy or cure for cataracts in the future.

In his study, K. Krishna Sharma, professor of ophthalmology at MU, observed that a specific type of protein begins to lose function as the eye ages. As the protein loses function, small peptides, made of 10 to 15 amino acids, start forming and accelerate cataract formation in the eye.

It is very helpful to track the formation of these peptides, Sharma said. The next step is to work on preventing their formation. If we are successful, we could delay the aging process in the eye. A ten-year delay in the onset of cataracts could decrease the number of cataract surgeries by 45 percent, thus significantly decreasing vision care cost. Currently, 1.5 million to 2 million cataract surgeries are completed yearly......... Posted by: Mike      Read more         Source

April 7, 2008, 10:50 PM CT

When poor communication pokes you in the eye

The ocular lens belongs to the optical apparatus and focuses incidental beams of light onto the retina. Now, a research team led by Professor Dr. Jochen Graw of the Institute of Developmental Genetics, of the Helmholtz Zentrum München, has been able to decipher a genetic defect responsible for small eyes and an incomplete, clouded lens in the so-called Aey12 mouse mutants. These results lead to conclusions concerning cataracts in humans, because, in this case too, the lens loses its transparency.

The development of the eye in mammals (and this naturally includes humans) is an extraordinarily complex process beginning in an early embryonic phase. The same applies also to the formation in healthy eyes of elastic and transparent lenses, which focus light beams. With the aid of the ciliary muscles, the lens can change its degree of curvature and thus set itself on varied, far distant objects. As a result, a pin sharp image is created on the retina. "As with humans, with mice too, the development of the lens starts with the formation of a spherical, hollow sac," Graw says. "That is the lens vesicle, the cover of which is surrounded by the lens epithelium, composed of a layer of cells. The vesicle is then filled in with fiber cells. In the following course of development, additional fibers originate in the equator of the lens. These scale up the diameter of the lens: a process that lasts a lifetime."........ Posted by: Mike      Read more         Source

March 9, 2008, 4:54 PM CT

Lasik Patients Report More Than 95 Percent Satisfaction Rate

Worldwide, an average 95.4 percent of LASIK patients are satisfied with their new vision, as per the first review of the world body of scientific literature, the American Society of Cataract and Refractive Surgery announced recently.

With 16.3 million patients having had LASIK worldwide, and more than a decade of clinical study and technological innovation behind it, LASIK is considered among the most successful elective procedures available today.

"We find that there is solid evidence in the world's scientific literature to affirm that there is an exceptionally high level of satisfaction in patients who have had LASIK surgery. While no surgery is perfect, certainly the 19 peer-evaluated studies of the 2,199 patients studied show extremely high satisfaction rates," said Richard L. Lindstrom, M.D., president of the American Society of Cataract and Refractive Surgery. "While patient satisfaction is extremely high, we recognize that there are patients who have unsatisfactory outcomes. As surgeons, we have taken the Hippocratic Oath. The well being of all of our patients is central to what we do and what we are. As such, and as the history of medicine has shown, we are committed to advancing our technology, patient selection, and surgical techniques so that we can continue to enhance the quality of our patient's lives," Lindstrom added......... Posted by: Mike      Read more         Source

March 3, 2008, 9:18 PM CT

Dry eye syndrome after LASIK surgery

Researchers at Schepens Eye Research Institute have observed that people with a certain low level of tear production are more likely to develop chronic dry eye syndrome after LASIK (laser-assisted in situ keratomileusis), laser refractive surgery to correct near- and far-sightedness than those with more plentiful tears. Their research, reported in the recent issue of Investigative Ophthalmology and Vision Science, may offer reliable prescreening criteria for ophthalmologists and patients.

These findings should help ophthalmologists determine if pretreatment is necessary before surgery or if surgery is appropriate at all for an individual, says Dr. Darlene Dartt, director of the Military Vision Research Program at Schepens Eye Research Institute and the principal investigator of the study.

Dry eye syndrome is one of the most common problems treated by eye physicians. Affecting more than 10 million Americans, it is caused by problems with the tear film responsible for lubricating the eye. While it does not cause vision loss, dry eye syndrome can be painful and severely decrease quality of life for its victims who constantly search for relief with artificial tears and other medications.

LASIK surgery uses small laser cuts to reshape the surface of the cornea, eliminating far-sightedness or near-sightedness, and the need for glasses or contacts. A number of people choose LASIK for cosmetic reasons. In recent years, thousands of military personnel have opted for LASIK surgery because it can help them see better and identify objects and people in the field more quickly. It also relieves them of the worry about lost or damaged glasses......... Posted by: Mike      Read more         Source

January 29, 2008, 10:08 PM CT

The eyes Tells It All

Using the radiocarbon dating method and special proteins in the lens of the eye, scientists at the University of Copenhagen and Aarhus can now establish, with relatively high precision, when a person was born. This provides a useful tool for forensic researchers who can use it to establish the date of birth of an unidentified body and could also have further consequences for health science research. The findings appear in the online, open-access journal PLoS ONE on January 30.

The lens of the eye is made up of transparent proteins called crystallins. These are packed so tightly together and in such a particular way, that they behave like crystals, allowing light to pass through the lens of the eye so that we can see. From conception and up until a human being is 1-2 years of age, the cells in the lens build these crystalline proteins. Once this organic construction work is done, however, the lens crystallins remain essentially unchanged for the rest of our lives. This is a fact that scientists can now put to good use.

A minute quantity of Carbon (C-12) in the carbon-dioxide content of the atmosphere contains two extra neutrons and is therefore called Carbon-14 (C-14). This isotope is radioactive, but decays so slowly and harmlessly into nitrogen, that this small carbon element, which occurs quite naturally in nature, is in no way harmful to humans, plants or animals......... Posted by: Mike      Read more         Source

January 17, 2008, 9:30 PM CT

Next Generation Optical Fibres

Researchers have discovered a way of speeding up the production of hollow-core optical fibres - a new generation of optical fibres that could lead to faster and more powerful computing and telecommunications technologies.

The procedure, described today in the journal Optics Express, cuts the production time of hollow-core optical fibres from around a week to a single day, reducing the overall cost of fabrication.

Initial tests show that the fibre is also superior in virtually every respect to prior versions of the technology, making it an important step in the development of new technologies that use light instead of electrical circuits to carry information.

These technologies include faster optical telecommunications, more powerful and accurate laser machining, and the cheaper generation of x-ray or ultra-violet light for use in biomedical and surgical optics.

"This is a major improvement in the development of hollow-core fibre technology," said Professor Jonathan Knight from the Centre for Photonics & Photonic Materials in the Department of Physics at the University of Bath.

"In standard optical fibres, light travels in a small cylindrical core of glass running down the fibre length.

"The fact that light has to travel through glass limits them in a number of ways. For example, the glass can be damaged if there is too much light......... Posted by: Mike      Read more         Source

January 17, 2008, 9:25 PM CT

Contact lenses with circuits

Movie characters from the Terminator to the Bionic Woman use bionic eyes to zoom in on far-off scenes, have useful facts pop into their field of view, or create virtual crosshairs. Off the screen, virtual displays have been proposed for more practical purposes -- visual aids to help vision-impaired people, holographic driving control panels and even as a way to surf the Web on the go.

The device to make this happen may be familiar. Engineers at the University of Washington have for the first time used manufacturing techniques at microscopic scales to combine a flexible, biologically safe contact lens with an imprinted electronic circuit and lights.

"Looking through a completed lens, you would see what the display is generating superimposed on the world outside," said Babak Parviz, a UW assistant professor of electrical engineering. "This is a very small step toward that goal, but I think it's extremely promising." The results were presented today at the Institute of Electrical and Electronics Engineers' international conference on Micro Electro Mechanical Systems by Harvey Ho, a former graduate student of Parviz's now working at Sandia National Laboratories in Livermore, Calif. Other co-authors are Ehsan Saeedi and Samuel Kim in the UW's electrical engineering department and Tueng Shen in the UW Medical Center's ophthalmology department......... Posted by: Mike      Read more         Source

January 6, 2008, 10:19 PM CT

Contact lenses purchased over Internet

Purchasing contact lenses online may save consumers time, but the process could cause more problems in the long run, as per a new study published in the recent issue of Optometry: Journal of the American Optometric Association. This research, which was conducted by Joshua Fogel, Ph.D., and Chaya Zidile of Brooklyn College, observed that individuals who did not purchase their contact lenses from an eye doctor, but from an online site or store, are potentially placing themselves at greater risk. The findings indicated that online and store purchasers (consumers who get their contacts at a wholesale club or optical chain outlet) are less likely to adhere to healthy eye care practices, as recommended by their eye doctor.

As per the Contact Lens Institute (CLI), more than 30 million individuals wear contact lenses. With the Fairness to Contact Lens Consumers Act taking effect in 2004, mandating that the prescribing eye doctor provide a copy of the contact lens prescription at no charge to the patient, consumers have the option to purchase their lenses (with a valid prescription) elsewhere. With the Internet becoming a more recognized source for health and medical information, consumers are increasingly purchasing their contact lenses online.

We observed that a pattern exists regarding the method of contact lens purchasing and following recommendations from the Food and Drug Administration (FDA), said Dr. Fogel. Those who bought contact lenses at their doctors office followed many FDA recommendations more so than those who bought contact lenses elsewhere......... Posted by: Mike      Read more         Source

December 28, 2007, 7:53 AM CT

Cost of glaucoma medications may impact treatment

In the United States, the management of glaucoma costs about $2.5 billion per year. Of the $1.9 billion in direct costs, glaucoma medications account for an estimated 38% to 52% of the total. In an article reported in the January 2008 issue of the American Journal of Ophthalmology, scientists from The Texas A&M University System Health Science Center College of Medicine, Temple, Texas; analyzed the economics of medically managing glaucoma. The yearly costs to patients of various topical glaucoma medications were calculated and significant price differences and increases in cost over time were found.

The scientists looked at four classes of pharmaceuticals; -blockers, prostaglandins, α2-agonists and carbonic anhydrase inhibitors. They compared both brand-name and generic formulations, reviewed how accurately the bottles were filled and how accurately the medications could be dispensed by patients. Using results from earlier studies, the increases in Average Wholesale Prices (AWP) were also reviewed from 1999 through 2006.

Nonselective -blockers remain the most inexpensive class of glaucoma medications. For all categories of drugs, calculated yearly cost ranged from $150.81 for generic timolol maleate 0.5% (-blocker), to $697.42 for Cosopt (combination formulation), to as high as $873.98 for a three-times-daily dose of Alphagan P 0.15% (α2-agonist). Among brand name -blockers, yearly cost ranged between $203.47 for Timoptic 0.5% and $657.24 for Betoptic S. Generic -blockers consistently were more economical than their brand-name counterparts. Yearly cost of prostaglandin analogs ranged from $427.69 for Travatan to $577.62 for Lumigan. The two carbonic anhydrase inhibitors, Azopt and Trusopt, yielded similar economic profiles. The generic selective α2-agonist brimonidine tartrate 0.2% costs approximately $352.89 and $529.34 per year for the respective two and three drops daily per eye regimens......... Posted by: Mike      Read more         Source

December 28, 2007, 7:47 AM CT

LASIK works well in highly myopic patients

Laser surgery to correct vision problems has been in use since the early part of 1990s. Photorefractive Keratotomy (PRK) is typically used to correct low to moderate myopia, while laser in-situ keratomileusis (LASIK) is preferred for high myopia corrections. Eventhough over 18 million LASIK procedures have been performed worldwide, there is still some controversy regarding the maximum correction possible and efficacy with this technique. In an article reported in the January 2008 issue of the American Journal of Ophthalmology, scientists from Miguel Hernandez University, Medical School, Alicante, Spain; and Ankara University School of Medicine, Ankara, Turkey; report on a study of high myopia patients ten years after LASIK surgery. The findings show that LASIK for myopia over -10 D is a safe and effective procedure in the long-term.

196 high myopic eyes of 118 patients, preoperatively needing at least 10 diopter (10 D) corrections to achieve 20/20 vision, were reviewed ten years following surgery. Uncorrected vision was 77% of best-corrected vision (BSCVA) before surgery. BSCVA improved 1 line. Only 5% of eyes lost more than 2 lines of BSCVA and 40% avoided the use of glasses. 119 (61 %) of eyes were within 2.00 Diopters at 10 years. Only 2 eyes (1%) developed corneal ectasia. The retreatment rate was 27%......... Posted by: Mike      Read more         Source

November 29, 2007, 10:42 PM CT

New treatment for age-related macular degeneration

With 8 million people at high risk for advanced age-related macular degeneration, scientists from Harvard and Japan discovered that the experimental drug, endostatin, may be the cure. A research report reported in the December 2007 issue of The FASEB Journal, describes how giving endostatin to mice significantly reduced or eliminated abnormal blood vessel growth within the eye, which is ultimately why the disease causes blindness.

Our study provides intriguing findings that may lead to a better therapy of age-related macular degeneration, said Alexander Marneros, the first author of the report, but clinical studies in patients with age-related macular degeneration are still necessary.

In this study, scientists describe testing the effects of endostatin on mice lacking this naturally occurring substance. The mice without endostatin were about three times more likely to develop advanced age-related macular degeneration (AMD) than normal mice. Then the scientists administered endostatin to both sets of mice. In the mice lacking endostatin, the number of abnormal blood vessels that cause AMD were reduced to normal levels. In control mice with normal levels of endostatin, the number of abnormal blood vessels were practically undetectable.

With Baby Boomers reaching advanced ages, new therapys are desperately needed to keep age-related macular degeneration from becoming a national epidemic, said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. This research provides hope for those at risk for blindness, and it gives everyone another glimpse of how investments in molecular biology will ultimately pay off in terms of new therapys and cures......... Posted by: Mike      Read more         Source

November 7, 2007, 9:32 PM CT

How the brain sends eyeballs bouncing

All vision, including reading this sentence, depends on a constant series of infinitesimal jumps by the eyeball that centers the retina on target objectswords or phrases in the case of reading. Such jumps, or saccades, are critical to vision because only the small central region of the retina, called the fovea, produces the clear image necessary for perception. Such saccades take place several times a second and are generated within a brain region known as the frontal eye field (FEF).

In studies with monkeys, Robert Schafer and Tirin Moore have taken an important step in understanding how circuitry of the FEF generates saccadeswith the FEFs attentional circuitry governing the motor circuitry that produces saccades. The scientists published their findings in the November 8, 2007, issue of the journal Neuron, published by Cell Press.

In a preview of the paper in the same issue of Neuron, Stefan Everling wrote that the scientists findings are exciting, because they demonstrate that attention and action interact more closely in the FEF than previously thought, and they suggest a mechanism by which attention can modulate saccade motor commands. Everling is at the University of Western Ontario in Canada.

In their experiments, Schafer and Moore took advantage of a well-known optical phenomenon involving the influence of the motion of a drifting grating on saccades that target the grating. The moving grating causes a motion-induced bias of saccades; for example, if the eye makes a saccade to a grating that is drifting upward, that saccade to the grating is biased to land higher than it would if the grating were stationary......... Posted by: Mike      Read more         Source

October 19, 2007, 5:05 AM CT

The specific cell that causes eye cancer

Investigators at St. Jude Children's Research Hospital have identified the cell that gives rise to the eye cancer retinoblastoma, disproving a long-standing principle of nerve growth and development. The finding suggests for the first time that it may one day be possible for researchers to induce fully developed neurons to multiply and coax the injured brain to repair itself.

A report of this work appears in the Oct. 19 issue of the journal Cell. Michael Dyer, Ph.D., an associate member in the St. Jude Department of Developmental Neurobiology, is the reports senior author.

Retinoblastoma arises in the retinathe multi-layered, membrane lining the back of the eye that responds to light by generating nerve impulses that are carried into the brain by the optic nerve.

The immediate importance of the St. Jude finding is that it unexpectedly showed that retinoblastoma can arise from fully matured nerves in the retina called horizontal interneurons. This disproves the scientific principle that fully formed, mature nerves cannot multiply like young, immature cells, Dyer said. Human neurodegenerative disorders such as Alzheimers disease can occur when differentiated nerves in the brain try to multiply, and in the process, trigger a self-destruct program called apoptosis. Differentiation is the process by which cells lose their primitive, stem-cell-like properties that include the ability to grow and multiply, and instead develop specialized shapes and functions......... Posted by: Mike      Read more         Source

October 15, 2007, 4:40 PM CT

Simple eye scan opens window to multiple sclerosis

A five-minute eye exam might prove to be an inexpensive and effective way to gauge and track the debilitating neurological disease multiple sclerosis, potentially complementing costly magnetic resonance imaging to detect brain shrinkage - a characteristic of the diseases progression.

A Johns Hopkins-based study of a group of 40 multiple sclerosis (MS) patients used a process called optical coherence tomography (OCT) to scan the layers of nerve fibers of the retina in the back of the eye, which become the optic nerve. The process, which uses a desktop machine similar to a slit-lamp, is simple and painless. The retinal nerve fiber layer is the one part of the brain where nerve cells are not covered with the fat and protein sheathing called myelin, making this assessment specific for nerve damage as opposed to brain MRI changes, which reflect an array of different types of tissue processes in the brain.

Results of the scans were calibrated using accepted norms for retinal fiber thickness and then in comparison to an MRI of each of the patients brains - also calibrated using accepted norms. Experimenters found a correlation coefficient of 0.46, after accounting for age differences. Correlation coefficients represent how closely two variables are related -- in this case MRI of the brain and OComputerized axial tomography scans. Correlation coefficients range from -1 (a perfect opposing correlation) through 0 (no correlation) to +1 (a perfect positive correlation). In a subset of patients with relapsing remitting MS, the most common form of the disease, the correlation coefficient jumped to 0.69, suggesting an even stronger association between the retinal measurement and brain atrophy......... Posted by: Daniel      Read more         Source

October 8, 2007, 8:32 AM CT

Limiting refined carbohydrates may stall AMD progression

Eating fewer refined carbohydrates may slow the progression of age-related macular degeneration (AMD), as per a new study from scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.

AMD results in partial or total blindness in 7 to 15% of the elderly, as per the Eye Diseases Prevalence Research Group. Dietary changes may be the most practical and cost-effective prevention method to combat progression of AMD, says Allen Taylor, PhD, director of the Laboratory for Nutrition and Vision Research at the USDA HNRCA. It is surprising there is so little attention focused on the relationship between AMD and carbohydrates.

The current study, reported in the recent issue of the American Journal of Clinical Nutrition, builds on a recent analysis by Taylor and his colleagues that found men and women older than 55 who consumed diets with higher-than-average dietary glycemic index foods appeared to have an increased risk for both early and later stages of AMD.

Dietary glycemic index is a scale used to determine how quickly carbohydrates are broken down into blood sugar, or glucose. Foods with a high glycemic index are linked to a faster rise and subsequent drop in blood sugar. Refined carbohydrates like white bread and white rice have high glycemic indices. Whole wheat versions of rice, pasta and bread are examples of foods with low glycemic indices......... Posted by: Mike      Read more         Source

September 25, 2007, 5:04 AM CT

Eye Movement Can Affect Problem-solving

A pair of Beckman Institute scientists has discovered that by directing the eye movements of test subjects they were able to affect the participants' ability to solve a problem, demonstrating that eye movement is not just a function of cognition but can actually affect our cognitive processes.

Prior research (Grant and Spivey, 2003) has shown a relationship between eye movements and problem-solving but Psychology Professor Alejandro Lleras, a member of the Human Perception and Performance group, and Ph.D. candidate Laura Thomas have taken that work in a groundbreaking direction.

They report in the current (Aug., 2007) issue of Psychonomic Bulletin and Review that by occasionally guiding the eye movements of participants with a tracking task uncorrelation to the problem, they were able to "substantially affect their chances of problem-solving success" to the point where those groups outperformed every control group at solving the problem. These results, they conclude, demonstrate that "it is now clear that not only do eye movements reflect what we are thinking, they can also influence how we think".

The prior work of Grant and Spivey suggested a relationship between eye movements and problem-solving by showing that certain patterns of eye movement were reflected as participants got closer to solving the problem......... Posted by: Mike      Read more         Source

September 11, 2007, 11:36 PM CT

Glaucoma surgery in the blink of an eye

Prof. Ehud Assia, of Tel Aviv Universitys Sackler School of Medicine is, quite simply, a rock star in the field of eye surgery.

One of a small number of surgeons in the world who currently perform a complicated form of glaucoma surgery, Prof. Assia has developed a novel laser device that promises to revolutionize therapy of the disease. The laser, called the OTS134 for now, is expected to give most practicing eye surgeons the ability to master complex glaucoma surgery very quickly.

Glaucoma, nicknamed the silent sight thief, is the second leading cause of blindness in the West. Glaucoma is a serious problem that starts to cause nerve damage to people without them realizing that anything is happening to their eyesight, often before it is too late, says Prof. Assia, who is also the director of Ophthalmology at Meir Hospital in Israel, which treats thousands of glaucoma patients each year.

The most common surgical therapy in use today perforates the wall of the eye, often resulting in collapse of the eyeball, infection, cataract formation and other complications. A more effective and elegant approach, a specialty of Prof. Assia's, involves penetration of the eye wall to a depth of only about 95 percent, leaving a razor-thin layer intact. The difference between success and failure may amount to just a few microns......... Posted by: Mike      Read more         Source

September 4, 2007, 7:16 PM CT

Promising Drug Combination For Ocular Melanoma

A combination of two drugs shows promise in treating a rare and treatment-resistant type of melanoma that originates in the eye and spreads to other organs, as per a new study led by Duke University Comprehensive Cancer Center researchers.

The drugs -- decitabine, which can turn on certain genes in cancer cells, and interferon gamma, an immune system protein -- may work together to cause cancer cell death.

"Metastatic uveal melanoma, or melanoma that originates in the eye and spreads to other parts of the body, has been very difficult to treat, in fact there have been no effective therapies to date," said Jared Gollob, M.D., a medical oncologist at Duke and lead investigator on the study. "This study could lead to a very promising new treatment for patients who previously had very little hope."

The scientists published their findings in the September 1, 2007 issue of the journal Clinical Cancer Research. The study was funded by the National Institutes of Health.

This pre-clinical study came on the heels of prior lab work examining proteins called interferons, which originate from immune system cells. These proteins were shown to boost immune function and directly affect melanoma cells, inhibiting their growth and accelerating their death, Gollob said......... Posted by: Mike      Read more         Source

August 27, 2007, 8:28 PM CT

Link Between Zinc And Macular Degeneration

A team of scientists, including three scientists at George Mason University, observed that the mineral zinc could play a role in the development of macular degeneration. In studying eye tissue samples, the researches observed that deposits, that are hallmarks of age-related macular degeneration (AMD), contain large amounts of zinc.

This finding, reported in the journal Experimental Eye Research, might be especially important because zinc supplements are widely given to patients to help boost weak immune systems. In addition, a 2001 study from the National Eye Institute observed that high doses of zinc supplements, combined with antioxidants, may postpone the progression to blindness.

AMD is a medical condition in which the macula, the place of central vision in the eye, experiences atrophy and in some cases bleeding. It is the primary cause of blindness in the elderly in Western society and approximately 13 million Americans suffer from the disease as per AMD Alliance International.

"Because earlier findings have shown that that zinc contributes to deposit formation in neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, we were prompted to test the theory that zinc might be involved in deposit formation in AMD," said Mason professor of psychology, Jane Flinn......... Posted by: Mike      Read more         Source

August 7, 2007, 10:52 PM CT

Miniature implanted devices could treat epilepsy, glaucoma

developed new miniature devices designed to be implanted in the brain to predict and prevent epileptic seizures and a nanotech sensor for implantation in the eye to treat glaucoma.

Findings will be detailed in three research papers being presented at the Engineering in Medicine and Biology Society's Sciences and Technologies for Health conference from Aug. 23-26 in Lyon, France.

One research project focuses on a tiny transmitter three times the width of a human hair to be implanted below the scalp to detect the signs of an epileptic seizure before it occurs. The system will record neural signals relayed by electrodes in various points in the brain, said Pedro Irazoqui (pronounced Ear-a-THOkee), an assistant professor of biomedical engineering.

"When epileptics have a seizure, a particular part of the brain starts firing in a way that is abnormal," Irazoqui said. "Being able to record signals from several parts of the brain at the same time enables you to predict when a seizure is about to start, and then you can take steps to prevent it".

Data from the implanted transmitter will be picked up by an external receiver, also being developed by the Purdue researchers.

The most critical aspect of the research is creating a device that transmits a large amount of data at low power. The transmitter consumes 8.8 milliwatts, or about one-third as much power as other implantable transmitters while transmitting 10 times more data. Another key advantage is that the transmitter has the capacity to collect data specifically correlation to epileptic seizures from 1,000 channels, or locations in the brain, Irazoqui said......... Posted by: Mike      Read more         Source

August 1, 2007, 9:12 PM CT

New Treatment For Glaucoma

Iowa State University scientists have developed a new technique that successfully treated rats for blindness caused by glaucoma. Their experimental therapy will be used on canine patients in the next year. If proved to be successful, it is expected to move to human trials.

An estimated 3 million people in the U. S. are affected by glaucoma, the second leading cause of blindness in the developed world and the number one cause of vision loss among blacks. People with elevated intraocular pressure are at greatest risk for developing glaucoma.

Iowa State scientists leading the six-year project are Dr. Sinisa Grozdanic, a veterinary ophthalmologist and assistant professor of veterinary clinical sciences; Donald Sakaguchi, neuroscientist and associate professor of genetics, development and cell biology; and Matt Harper, doctoral student in neuroscience. The team also included scientists from the University of Iowa, Yale University, Tulane University and the University of Miami. The work was presented at a recent meeting of the Association for Research in Vision and Ophthalmology Conference.

The scientists previously determined that animals with glaucoma increase production of proteins with neuron-protective capabilities (neurotrophins) in an attempt to shield against blindness. So, they imitated that process in the laboratory, modifying bone marrow-derived stem cells. Then they transplanted the cells into the eyes......... Posted by: Mike      Read more         Source

July 5, 2007, 9:24 PM CT

Holograms make for better vision tests

A new paper reported in the July 1 issue of OSA's Optics Letters shows that scientists in Australia have created a new one-step test that uses holograms to diagnose the astigmatic error of the human eye, a key measurement in determining the appropriate prescriptions for eye glasses in patients. This new technique adds to an earlier one, developed by the same researchers, for using a single hologram to measure another important property, the spherical refractive error of the eye.

Summary

In this new test, patients view a hologram consisting of sunburst patterns; by reporting which sunburst lines appear clearest, the eye doctor can obtain information he or she can use in determining the correct prescription for the patient. Traditionally, patients look through a series of lenses until they find which one gives each eye the clearest view of a distant target such as an eye chart on a wall. This multi-step process of finding the right lens can be cumbersome and complex. Holography offers a number of advantages including simplicity, high speed and low cost and could open new doors in our understanding of human vision. This approach still needs to be tested on young astigmatic individuals, whose nature of vision is not fully known. The same method has also been found to work well in measuring the refractive error of non-astigmatic subjects. The results of that research will appear in a future issue of OSAs journal JOSA-A......... Posted by: Mike      Read more         Source