Month: May 2013

HOUSTON, March, 2006 ??” The University of Houston, University Eye Institute and the National Multiple Sclerosis Society are partnering to open a new clinic to evaluate the eyes of patients with multiple sclerosis and those who are multiple sclerosis suspects.

A joint press conference will announce the opening of the Multiple Sclerosis Eye Center for Analysis, Research and Education (MS Eye CARE) at 11:30 a.m., Monday, March 6.

Located in the University Eye Institute on the UH campus, the new center is currently the only one of its kind where the MS Society has affiliated directly with an eye institute. Now a formal affiliate of the National MS Society, this center is dedicated to the eye care of adults and children with MS and patients who are MS suspects.

“What differentiates us from other MS centers is our focus on recognizing and studying the very early visual and eye movement findings as they relate to MS,” said Jade S. Schiffman, M.D., the facility’s medical director. “Early signs of MS are easily overlooked. A goal of MS Eye CARE is to help health care professionals recognize the early eye manifestations suggestive of MS and to serve as a referral center for MS prospects. This is especially important for eye care professionals, who are often the first health care professionals to see MS patients, since in almost half of the cases the initial symptoms often involve the eyes.”

Dr. Schiffman is an associate professor at UH and a member of the Methodist Neurological Institute in the Texas Medical Center. She is board certified in both neurology and ophthalmology and has subspecialty training in neuro-ophthalmology. She has been recognized in the Best Doctors in America for the past 12 years. The center’s research director is Laura Frishman, the associate dean for graduate studies and research for UH’s College of Optometry and an internationally recognized expert in the visual system. Both work together with Ph.D.s in physiological optics to blend clinical, electrophysiological and other new technology to aid in the early diagnosis of MS.

MS can cause myriad symptoms, including blurred vision, blindness, eye pain, double vision, dizziness, loss of balance, poor coordination, slurred speech, tremors, numbness, extreme fatigue, problems with memory and concentration, paralysis and others. Some of these symptoms initially may be transient, making early diagnosis difficult. MS Eye CARE has developed protocols that will facilitate early diagnosis and will provide initial measures of progression of the disease.

“The symptoms of MS mimic a wide range of diseases and can easily be attributed to something else for a number of years until they become severe enough to be recognized as being caused by MS,” she said. “Using the latest diagnostic technology and working with neurologists, we are able to confirm the diagnosis even when symptoms may have temporarily resolved. Early diagnosis is extremely important in the management of MS because progression can be slowed down by relatively new medications and the patient’s quality of life enhanced if treatment is initiated early. The ability to provide a patient suspected to have MS with an alternative diagnosis is also equally important.”

Additional goals of MS Eye CARE include direct rehabilitation to patients with disabling visual symptoms and referrals to neighboring clinics in the University Eye Institute, such as the Center for Sight Enhancement. MS Eye CARE also works with treating neurologists at collaborating medical facilities that include the Maxine Messinger MS Center, The University of Texas Health Science Center at Houston’s MS group, Texas Children’s Hospital and other outside neurologists who are caring for MS patients.

“There is a finite window of opportunity in detecting MS,” said Mark Neagli, president of the National MS Society, Lone Star Chapter. “Prompt diagnosis is important, because early treatment has been proven to lessen the destruction caused by MS. This is a crucial partnership in fighting this disease and setting our sights on stopping MS in its tracks.”

The National Multiple Sclerosis Society’s first MS Awareness Week begins March 13.

About the University of Houston
The University of Houston, Texas’ premier metropolitan research and teaching institution, is home to more than 40 research centers and institutes and sponsors more than 300 partnerships with corporate, civic and governmental entities. UH, the most diverse research university in the country, stands at the forefront of education, research and service with more than 35,000 students.

About the National MS Society, Lone Star Chapter
Celebrating more than 50 years in the fight against multiple sclerosis, the Lone Star Chapter serves more than 17,000 people affected by multiple sclerosis in 141 Texas counties. The chapter is number one in the nation financially, geographically and in terms of population served. While there is no cure yet, FDA-approved medications can significantly reduce the number of acute attacks and delay the onset of permanent disabilities. All funds are privately raised and 83 cents of every dollar is used to benefit persons affected by multiple sclerosis. The Lone Star Chapter has offices in Houston, Dallas, San Antonio, Austin and Corpus Christi.

Studies show that early and ongoing treatment with an FDA-approved therapy can reduce future disease activity and improve quality of life for many people with multiple sclerosis. Talk to your health care professional and contact the National MS Society at www.nationalmssociety or 1-800-FIGHT-MS to learn about ways to help manage MS and about current research that may one day reveal a cure.

About the UH College of Optometry
For more than 50 years, the University of Houston College of Optometry (UHCO) has trained optometrists to provide the highest quality vision and eye care. One of only 17 optometry schools in the United States, the UHCO offers a variety of degree programs including: Doctor of Optometry (O.D.), a combined Doctor of Optometry / Doctor of Philosophy (O.D./Ph.D.), Master of Science (M.S.) and a Doctor of Philosophy (Ph.D.). Located on the UH campus, the UHCO consists of 50 full-time faculty, 508 adjunct faculty as well as 76 full-time staff.

For more information about UH, visit the university’s Newsroom at uh.edu/newsroom.

To receive UH science news via e-mail, visit uh.edu/admin/media/sciencelist.html

Contact: Lisa Merkl
lkmerkluh.edu
University of Houston

Age-related Macular Degeneration (AMD), which affects more than 10 million older Americans, continues to be the leading cause of vision loss in the United States. The global cost of the disease according to a recent report by AMD Alliance International (AMDAI) is estimated at $343 billion, underscoring the need for swift actions to raise awareness of prevention and treatment options.

During this year’s AMD Week, which runs from September 18-26, AMDAI, along with some of the leading eye-care organizations from 25 countries, has issued a call to action to doctors, patients and caregivers through the public awareness campaign “Don’t Surrender to AMD.”

“This is a promising time for patients as preventative measures and effective, timely treatments have the ability to alter the disease tremendously,” said AMDAI’s Chairman Don Curran. “But macular disease is only as preventable and manageable as people are knowledgeable. Knowing the facts can significantly improve a person’s chances of maintaining healthy vision and a better quality of life.”

The National Institutes of Health projects the number of AMD diagnoses to double to 20 million by 2020. Losing vision has devastating consequences to an individual’s daily life and those affected by the disease often suffer from severe depression and loss of independence.

However, those at-risk and AMD patients can take steps to reduce needless sight loss. AMD can be prevented or slowed down if a person takes action to keep his or her vision healthy. Along with regular eye exams, the first step is a healthy lifestyle (Don’t smoke, take exercise, eat healthily and use sunglasses in bright sunlight). Specially formulated vitamins for those affected by the disease may help, and effective clinically-approved treatments are available for the most severe form of AMD.

In addition, low vision rehabilitation and support services can significantly help patients live with the disease and make the most of their remaining vision.

“AMD is a disease that we can prevent and manage,” says Dr. Alan Cruess, Chairman of AMD Alliance International’s Scientific Advisory Panel. “We have the ability to save the sight of many Americans each year.”

Through its “Don’t Surrender to AMD” campaign, AMDAI has increased public education efforts – which will span across print, radio, and digital media, including an interactive e-card – to inform the public of preventative measures and treatment options that are available in the fight against AMD.

MORE ABOUT AMD

Age-related Macular Degeneration or AMD is an eye disease that causes loss of central vision, leaving only peripheral, or side, vision intact. It usually does not lead to total blindness, but rather may cause foggy or blurred central vision and varying degrees of usable peripheral vision. Whether you have the more common “dry” (early) form of AMD, or the more severe (late stage) “wet” form, it is important to know the facts about AMD and what you can do to make the most of your sight.

If you take certain measures to keep your eyes healthy, you can prevent AMD or slow its progress. AMD Alliance International suggests taking the following three steps to help prevent and manage AMD.

Get regular eye exams and manage your eye health

— Routine exams can help identify AMD and other eye problems in their early stages, when many diseases are more easily treatable.

— Don’t smoke, eat a healthy varied diet, take exercise and use UV certified sunglasses in bright sunlight.

Understand the risk factors for AMD

— If you are 50 or older, you’re at risk of developing the disease. Having a family member with AMD can also increase your risk.

— Smoking, a diet high in saturated fat, obesity, and having high blood pressure are risk factors associated with AMD.

Ask questions and know your treatment options

— Know your exact diagnosis and all available treatment options.

Source: AMDAI

Our eyes are constantly making saccades, or little jumps. Yet the world appears to us as a smooth whole. Somehow, the brain’s visual system “knows” where the eyes are about to move and is able to adjust for that movement. In a paper published online this week in Nature, researchers at the University of Pittsburgh and the National Eye Institute (NEI) for the first time provide a circuit-level explanation as to why.

“This is a classic problem in neuroscience,” says Marc Sommer, assistant professor of neuroscience at Pitt, who coauthored the paper with Robert Wurtz, senior investigator at NEI, one of the National Institutes of Health. “People have been searching for a circuit to accomplish this stability for the last 50 years, and we think we’ve made good progress with this study.”

In 1950, Nobel laureate Roger Sperry hypothesized that when the brain commands the eyes to move, it also sends a corollary discharge, or internal copy, of that command to the visual system. Sommer and Wurtz showed in a 2002 Science paper that a pathway from brainstem to frontal cortex conveys a corollary discharge signal in the brains of monkeys. They suggested that this pathway might cause visual neurons of the cortex to suddenly shift their receptive field–their window on the world–just before a saccade. Such neurons with shifting receptive fields had been discovered by Pitt Professor of Neuroscience Carol Colby and colleagues in 1992.

In their current paper, which will be published in the Nov. 16 print edition of Nature, Sommer and Wurtz completed the circuit. They showed that the receptive fields in cortex are shifted because of the corollary discharge from the brainstem. To do this, they exploited the fact that the signals are relayed via the thalamus, a crucial intermediary. By knocking out the relay neurons, they interrupted the pathway. They found that receptive field shifts were curtailed by more than half.

A similar circuit is likely to exist in human brains, the researchers say. With this study, Sommer and Wurtz also provide a framework for studying corollary discharge in other sensory systems, such as hearing: Even when you move your head around, you still hear sounds around you as coming from the same place.

In future studies, Sommer and his graduate students at Pitt will perform the first direct test of the visual stability hypothesis. To determine whether shifting receptive fields are responsible for visual stability, the shifts will be disrupted in monkeys trained to detect visual motion. The monkeys could then report whether their world appears to be moving around abnormally as eye movements are made.

This research was supported by the NEI.

Contact: Karen Hoffmann

University of Pittsburgh

A small group of patients with severe Graves’ eye disease experienced rapid improvement of their symptoms and improved vision following treatment with the drug rituximab.

Inflammation around their eyes and damage to the optic nerve were significantly reduced. The same patients had not previously responded to steroids, a common treatment for Graves’ eye disease.

Raymond S. Douglas, M.D., Ph.D., an oculoplastics specialist who recently joined the faculty of the U-M Kellogg Eye Center, reports on the potential of the drug in the online October issue of Ophthalmology. Douglas reviewed the progress of six patients he treated while on the faculty of the University of California at Los Angeles.

Graves’ eye disease is an autoimmune disease that causes inflammation and fatty deposits in the eye muscles and connective tissue surrounding the eye. Among the symptoms are pronounced bulging eyes, retracted eyelids, dry eyes, and, in severe cases, loss of vision. Women are more likely than men to develop the disease.

The study suggests that rituximab is a potentially effective new treatment for the most severe forms of Graves’ eye disease. “These patients had already received the maximum level of steroid treatment,” says Douglas. “Treatment with rituximab calmed inflammation, stopped progression of the disease, and saved the patients from having to undergo surgery.”

Rituximab has been used to treat patients with other autoimmune diseases, including rheumatoid arthritis and in non-Hodgkin’s B-cell lymphoma. The drug works by depleting B cells the body’s normal antibody-producing cells that appear to go awry in autoimmune diseases.

Collaborating with Terry J. Smith, M.D., the Frederick G.L. Huetwell Professor of Ophthalmology and Visual Sciences, Douglas has helped to explain the process by which the immune system attacks the orbital tissue in Graves’ eye disease. In an earlier study, the researchers reported that B cells play a pivotal role in the inflammatory process in Graves’ eye disease.

In the current study, Douglas observed improvement among the patients, four of whom were women, as early as four weeks following the first infusion of rituximab. Researchers also observed that the positive results were sustained 4 to 6 months after treatment.

“Treatment of the inflammatory component of Graves’ eye disease has not advanced appreciably over several decades,” says Douglas. High-dose steroids, sometimes in combination with orbital radiation, are still the first line treatment. But, says Douglas, “These are imperfect options because inflammation often recurs when the treatment ends.” He is hopeful that rituximab can offer sustained improvement.

Douglas observes that the results from a small case series must be viewed with some caution. But given the substantial benefits for patients treated with rituximab, he sees good reason to proceed with a large-scale clinical trial to test this promising new drug.

Reference: Rituximab treatment of patients with severe, cortiocosteroid-resistant thyroid-associated ophthalmopathy, Ophthalmology, DOI: 10.1016/j.ophtha.2009.05.029
The paper will appear in the January print edition.

Other authors: Dinesh Khanna, Kelvin Chong, Nikoo Afifiyan, Catherine Hwang, Diana Lee, Helene Chokron Garneau, Robert Goldberg, Christine Darwin. (These authors represent the David Geffen School of Medicine, UCLA; Los Angeles Biomedical Institute at Harbor-UCLA Medical Center; Greater Los Angeles Veterans Administration; and the Chinese University of Hong Kong.)

Funding: National Institutes of Health, Research to Prevent Blindness (including a Research to Prevent Blindness Career Development Award), and the Bell Charitable Foundation.

Source: University of Michigan Health System

The eyes may or may not be windows to the soul, as the old adage goes, but scientists are reporting evidence that a peek into the eyes of cattle may become the basis for a long-sought test to detect infection with the agent that causes Mad Cow Disease. That test could help prevent the disease from spreading in the food supply. A study on using the tell-tale glow given off by eyes infected with the Mad Cow agent appears in ACS’ semi-monthly journal Analytical Chemistry.

Jacob Petrich and colleagues note that the human form of Mad Cow Disease is linked to eating beef from animals infected with abnormal proteins called prions implicated in a range of brain diseases. Scientists are trying to develop tests to detect infected cattle before they enter the food supply. Past studies suggest that chemical changes in an animal’s retina, the light sensitive nerve tissue in the back of the eye, may provide a basis for detecting prion diseases.

The scientists showed that retinas of sheep infected with scrapie, a disease similar to Mad Cow Disease, emit a characteristic glow when examined with a beam of light from a special instrument. They suggest that eye tests based on the finding could become important in the future for fast, inexpensive diagnosis of prion diseases and other neurological diseases.

Article:
“Fluorescence Spectroscopy of the Retina for Diagnosis of Transmissible Spongiform Encephalopathies”

Source:
Michael Bernstein
American Chemical Society

Sirna Therapeutics,
Inc. (Nasdaq: RNAI), a leading RNAi-based therapeutics company, reported
the final results from its recently completed Phase 1 trial for Sirna-027,
a novel therapeutic for age-related macular degeneration (AMD). Single
ascending doses of Sirna-027 were safe and well tolerated, and all 26
patients (100%) showed visual acuity stabilization eight weeks after a
single injection. In addition, at the same time point, five of 26 patients
(19%) experienced clinically significant improvement in visual acuity,
indicated by an increase of at least three lines on an eye chart.

Three months after a single injection, 24 of 26 patients (92%) showed
visual acuity stabilization, with four of 26 patients (15%) experiencing
clinically significant improvement in visual acuity; only two of 26
patients (8%) experienced a reduction in visual acuity of three lines or
more. Importantly, a decrease in foveal thickness was observed in some
patient groups, which is an indication of biological activity of Sirna-027.

“This is the first demonstration of biological activity of a chemically
optimized siRNA in humans,” said Sirna Chief Medical Officer Roberto
Guerciolini, M.D. “These data represent an important milestone toward the
demonstration of the potential therapeutic benefit of Sirna-027 and the
clinical validation of RNAi as a therapeutic modality.”

The potential for a long-lasting effect on visual acuity after a single
dose of Sirna-027 could be due to the unique catalytic mechanism of short
interfering RNA (siRNA), and could make this compound amenable to a more
favorable dosing regimen than other approved products.

“Less frequent dosing in this devastating disease should greatly
improve patient convenience, compliance, and quality of life,” said Dr.
Guerciolini.

The Phase 1 study evaluated the safety, tolerability, and biological
effect of single-ascending doses of Sirna-027 in patients with AMD. A total
of 26 patients with active disease were enrolled to receive a single
intravitreal injection of Sirna-027 ranging from 100-1,600 micrograms.

In September 2005, Sirna and Allergan, Inc., a global leader in eye
care, established a Strategic Alliance in eye diseases which includes
Sirna-027 for AMD. Under the terms of the Agreement, Allergan assumed all
developmental and commercialization costs for Sirna-027. Sirna and Allergan
expect to initiate the Phase 2 trial during the second half of 2006.

About Sirna Therapeutics

Sirna Therapeutics is a clinical-stage biotechnology company developing
RNAi-based therapies for serious diseases and conditions, including age-
related macular degeneration (AMD), hepatitis B and C, dermatology, asthma,
respiratory syncytial virus (RSV), Huntington’s disease, diabetes and
oncology. Sirna Therapeutics completed its Phase 1 clinical trial for
Sirna- 027 in AMD in 2005 and with its strategic partner, Allergan, Inc.,
will move Sirna-027 into Phase 2 clinical trials in the second half of
2006. Sirna has selected a clinical compound for hepatitis C virus,
Sirna-034, which the Company plans to bring into Phase 1 clinical trials by
the end of 2006. Sirna has established an exclusive multi-year strategic
alliance with GlaxoSmithKline for the development of siRNA compounds for
the treatment of respiratory diseases. Sirna has a leading intellectual
property portfolio in RNAi covering over 250 mammalian gene and viral
targets and over 200 issued or pending patents covering other major aspects
of RNAi technology, including the microRNA technology. More information on
Sirna Therapeutics is available on the Company’s web site at sirna.

Safe Harbor Statement

Statements in this press release which are not strictly historical are
“forward-looking” statements which should be considered as subject to many
risks and uncertainties. For example, most drug candidates do not become
approved drugs. The development of Sirna-027 and Sirna-034 as well as
Sirna’s other programs are still at a relatively early stage. All of these
programs, and Sirna’s ability to obtain milestone and royalty payments for
them, are subject to significant risks and unknowns, are highly contingent
upon future successes, and require significant funding. In addition, patent
applications may not result in issued patents, and issued patents may not
be enforceable or could be invalidated. Other risks and uncertainties
include, among others, Sirna’s early stage of development and short
operating history, Sirna’s history and expectation of losses and need to
raise capital, Sirna’s need to obtain clinical validation and regulatory
approval for Sirna-027, Sirna-034 and Sirna’s other product candidates, any
of which could have negative results, Sirna’s need to engage collaborators,
Sirna’s need to obtain and protect intellectual property, and the risk of
third-party patent infringement claims. These and additional risk factors
are identified in Sirna’s Securities and Exchange Commission filings,
including Forms 10-K and 10-Q and in other SEC filings. Sirna undertakes no
obligation to revise or update any forward- looking statements in order to
reflect events or circumstances that may arise after the date of this
release.

Sirna Therapeutics, Inc.
sirna

Corrected vision impairment could prevent billions of dollars in lost productivity annually, according to a study by researchers from the Johns Hopkins Bloomberg School of School of Public Health, the International Centre for Eyecare Education, the University of New South Wales and the African Vision Research Institute. Researchers estimate that nearly 158 million people globally suffer with vision impairment resulting from uncorrected refractive error, which can usually be eliminated with a pair of eyeglasses and an eye examination. This is the first study to estimate the productivity loss from uncorrected refractive error and is published in the June 2009 issue of the Bulletin of the World Health Organization.

“The economic gains that could be made if eyeglasses were provided to everyone in need are substantial,” said Kevin Frick, author of the study and an associate professor with the Bloomberg School’s Department of Health Policy and Management. “Our research estimates $269 billion in productivity lost and nearly 158 million people are vision-impaired because of uncorrected refractive error – which is correctable. The Western Pacific region, which includes China and Vietnam, has the highest estimated number of cases of uncorrected refractive error at 62 million and is responsible for almost half of the potential loss of productivity. The Southeast Asia region, encompassing Bangladesh, India and Nepal, has 48.7 million cases.”

Frick, along with colleagues, used conservative assumptions and national data to estimate the purchasing power, parity-adjusted gross domestic product loss for individuals with impaired vision and blindness, and for individuals with normal sight who provide them with informal care. Researchers found that uncorrected refractive error has a potentially greater impact on the global economy than all other preventable vision disorders despite low-cost interventions such as eyeglasses.

“Apart from the moral obligation, this research indicates that there is a tremendous loss of human potential and lost productivity associated with avoidable blindness and impaired vision due to uncorrected refractive error,” said Frick.

“Potential lost productivity resulting from the global burden of uncorrected refractive error” was TST Smith, KD Frick, BA Holden, TR Fricke and KS Naidoo.

Source:
Natalie Wood-Wright

Johns Hopkins University Bloomberg School of Public Health

Need a little extra incentive to kick the habit?

Just in time for New Year’s resolutions, a UCLA study finds that even after age 80, smoking continues to increase one’s risk for age-related macular degeneration (AMD), the leading cause of blindness in Americans over 65.

The American Journal of Ophthalmology publishes the findings in its January edition.

“The take-home message is that it’s never too late to quit smoking,” said lead author Dr. Anne Coleman, professor of ophthalmology at the Jules Stein Eye Institute at UCLA. “We found that even older people’s eyes will benefit from kicking the habit.”

AMD causes progressive damage to the macula, the center of the retina that allows us to see fine details. When the macula degenerates, people experience darkness or blurring in their central vision, preventing them from being able to read, drive and recognize faces.

After age, smoking is the second most common risk factor for AMD. This study sought to determine whether age influences the effects of smoking on AMD risk.

Coleman and her colleagues followed a group of 1,958 women who underwent retinal photographs at five-year intervals, starting with a baseline exam at age 78. Four percent, or 75 of the women, smoked.

The researchers compared the retinal images at ages 78 and 83 to check for the appearance of AMD, and evaluate whether smoking affected the women’s likelihood of developing the disease.

“Age is the strongest predictor for AMD, yet most of the research in this field has been conducted in people younger than 75,” explained Coleman. “Our population was considerably older than those previously studied. This research provides the first accurate snapshot of how smoking affects AMD risk later in life.”

Overall, women who smoked had 11 percent higher rates of AMD than other women their same age. In women over 80, however, those who smoked were 5.5 times more likely to develop AMD than women their age who did not smoke.

“We saw a slightly higher rate of AMD in women after age 80, but the rate was dramatically higher in older women who smoked,” said Coleman. “The bottom line is that AMD risk increases with age. And if you smoke, your risk of developing the disease rises even more.”

Cigarette smoking has been hypothesized to increase AMD risk by reducing serum antioxidant levels, altering blood flow to the eyes and decreasing retinal pigments.

“This study provides yet another compelling reason to stop smoking and suggests that it is never too late to quit,” said Dr. Paul Sieving, director of the National Eye Institute.

The National Eye Institute and National Institute on Aging funded the research. About 1.75 million U.S. residents suffer from advanced AMD with vision loss; the number is expected to grow to almost 3 million by 2020.

Coleman’s coauthors included Carol Mangione, Robin Seitzman and Fei Yu of UCLA; Steven Cummings and Katie Stone of the California Pacific Medical Center Research Institute; Jane Cauley from the University of Pittsburgh; Kristine Ensrud from the University of Minnesota; Marc Hochberg from the University of Maryland; Kathryn Pedula from the Kaiser Permanente Center for Health Research; and Edgar Thomas from the Retina Vitreous Associates Medical Group.

Source: University of California, Los Angeles

Perceived facial similarity of children is effectively an estimate of the probability that two children are close genetic relatives according to a new study recently published in Journal of Vision, an online, free access publication of the Association for Research in Vision and Ophthalmology (ARVO).

Participants in the study judged pairs of pictures of children, half of which portrayed actual siblings. In one condition, participants were only asked to rate the facial similarity of each pair of children. In a second condition, participants were asked to classify each pair as sibling or non-siblings. Researchers found that the mean similarity ratings of the first group contained as much information about genetic relatedness as did the actual judgments of genetic relatedness by the second group. These ratings could also be transformed into accurate estimates of the probability that a given pair of children portrayed siblings. The study was conducted by researchers Laurence T. Maloney, of New York University’s Psychology Department and Center for Neural Science, and Maria F. Dal Martello, of the Department of General Psychology at the University of Padova in Italy.

“We have shown that a complex, difficult to characterize perceptual judgment (‘facial similarity’) can be simply defined in evolutionary terms: judged facial similarity of children appears to be little more than a visual assessment of genetic relatedness,” said Maloney.

You can read this article online in Journal of Vision.

Journal of Vision is published by ARVO, the Association for Research in Vision and Ophthalmology. All articles are free and open to anyone.

Established in 1928, The Association for Research in Vision and Ophthalmology, Inc. (ARVO) is a membership organization of more than 11,500 eye and vision researchers from over 70 countries. The Association encourages and assists its members and others in research, training, publication and dissemination of knowledge in vision and ophthalmology. ARVO’s headquarters are located in Rockville, Md. The Association’s Web site is arvo/.

Contact: Elinore Tibbetts

Association for Research in Vision and Ophthalmology

Every year, in Germany alone, around 7000 people wait for a new cornea to save their eyesight. But donor corneas are in short supply. In an EU project, researchers have developed an artificial cornea which is to be clinically tested in early 2008.

A patient whose cornea is damaged through a congenital malformation, hereditary disease or corrosion is at risk of going blind. One solution is to implant a donor cornea. The central part of the natural cornea is removed in a circular fashion, and the new cornea is inserted and sutured in place. A vast number of patients are affected: every year, 40,000 people in Europe alone hope for a donor often in vain. Many attempts have therefore been made at producing artificial corneas, so far with little success. This is due to the conflicting requirements imposed on the material: While it has to grow firmly into the natural tissue at the edge, it must allow no cells to deposit themselves at the center of the cornea, as this impairs the patient’s vision.

Working with other colleagues in the EU-funded CORNEA project, research scientists at the Fraunhofer Institute for Applied Polymer Research IAP in Potsdam and the Department of Ophthalmology at the University Hospital of Regensburg have found a solution. “Our artificial corneas are based on a commercially available polymer which absorbs no water and allows no cells to grow on it,” says IAP project manager Dr. Joachim Storsberg. “Once our partner Dr. Schmidt Intraokularlinsen GmbH has suitably shaped the polymers, we selectively coat the implants: We lay masks on them and apply a special protein to the edge of the cornea, which the cells of the natural cornea can latch onto. In this way, the cornea implant can firmly connect with the natural part of the cornea, while the center remains free of cells and therefore clear.” What is special about this protein is that it can survive the later thermal sterilization of the artificial cornea without being damaged, as it does not have the three-dimensional structure typical of large proteins. Such a structure would be destroyed during the sterilization process, leading to changes in the material’s properties. The optical front part of the implant is coated with a hydrophilic polymer, so that it is constantly moistened with tear fluid.

Researchers in Dr. Karin Kobuch’s working group at Regensburg University Hospital have already tested these corneas in the laboratory and found that their cells graft very well at the edge and cease growing where the coating stops. The optical center of the implant thus remains clear. The first implants have already been tested in rabbits’ eyes with promising results. If further tests are successful, the technology will be tried on humans in 2008.

FRAUNHOFER-GESELLSCHAFT
Hansastra??e 27C
80686 Muenchen
fraunhofer.de