Month: January 2014

A study that appears in the May edition of Ophthalmology, the clinical journal of the American Academy of Ophthalmology,
shows that as many as 47 percent of patients receiving glaucoma therapy do not comply with their doctor’s prescribed medicine
regimen. This is in startling contrast to the 90 percent of doctors who believe that their patients are following the
prescribed treatment.

“Non-adherence to the glaucoma therapy is probably what causes patients to go blind,” said Alan L. Robin, M.D., author of the
study and Academy member. “Cost of medications, multiple medications, confusing instructions all contribute to a patient’s
non-compliance to their therapy.”

Dr. Robin refers to a 2003 Harris poll that illustrates this emerging health concern:

— One-third of patients surveyed took their medications less often than directed
— One-quarter delayed refilling prescriptions
— One-fifth failed to fill prescriptions
— One-fifth stopped taking a medication sooner than prescribed

The World Health Organization (WHO) estimates that worldwide, fifty percent of patients take medications improperly, at a
global cost of more than $100 billion in resulting hospital admissions and lost productivity.

Dr. Robin’s study compares medication refill rates for two groups of glaucoma patients. The first group takes a single
medication for one year without needing a second medication to control intraocular pressure. The second group takes the same
single glaucoma medication for one year, but then a second glaucoma medication is added for an additional year. As soon as a
second medication is added, approximately one-half of the second group delayed refilling prescriptions of the first
medication by 5 days or more, and 22 percent waited an additional 15 days or more to pick up their pills.

“Non-compliance is a bigger problem then we imagined, and glaucoma therapy is only the tip of the iceberg,” added Dr. Robin.
“It becomes a life-and-death situation for doctors to educate and motivate their patients on their therapy and with glaucoma;
this may lead to visual disability and blindness.”

Dr. Robin’s study suggests that eye diseases including glaucoma are one of the five conditions at the bottom of the medical
condition adherence list. The four other ailments include renal and pulmonary diseases, diabetes, and sleep disorders.

Dr. Robin is an associate professor at both the Johns Hopkins University Schools of Medicine and Public Health. To schedule
an interview with Dr. Robin, or to request a copy of the study titled “Does Adjunctive Glaucoma Therapy Affect Adherence to
the Initial Primary Therapy?” please contact the Academy’s media relations department at 415-561-8534, or at mediaaao.

The American Academy of Ophthalmology is the world’s largest association of eye physicians and surgeons–Eye M.D.s–with more
than 27,000 members. To find an Eye M.D. in your area, visit the Academy’s Web site at aao.

Contact: Media Relations
mediaaao
415-561-8534
American Academy of Ophthalmology
aao

A new University of Illinois at Chicago study appearing in the online edition of the journal Ophthalmology reports on the safety, efficacy and predictability of laser eye surgery (laser in situ keratomileusis or LASIK) in patients 40-69 years old.

“We are seeing an increasing demand for LASIK surgery for older adults, who present special challenges,” said study co-author Dr. Dimitri Azar, Field chair of ophthalmologic research at UIC.

In LASIK surgery, adjustments in correction are routinely made to compensate for the cornea’s strong healing responses in younger patients, Azar said. Increased age has been previously associated with poorer final clarity of vision, as measured on an eye chart (visual acuity).

“We were able to show that fine adjustments in the correction to the cornea in our older patients that compensate for differences in age-related healing resulted in reliable predictability of correction,” said Azar, who is also professor and head of the UIC department of ophthalmology and visual sciences.

The researchers examined the case histories of 710 consecutive laser eye surgeries on 424 patients between 40-69 years old. The LASIK surgeries were performed to correct myopia (nearsightedness), hyperopia (farsightedness) and astigmatism. All surgeries were performed by Azar between January 1999 and September 2005.

The cases were divided into three groups based on age: group one, 40-49 years old (359 eyes); group two, 50-59 years old (293 eyes); and group three, 60-63 years old (58 eyes).

Outcomes of the laser surgery corrections were analyzed for near-sightedness with or without astigmatism (511 eyes) and far-sightedness with or without astigmatism (199 eyes). Patients’ outcomes included a follow-up of at least six months and, where possible, 12 months. The study found no difference in safety between the groups.

At the final follow-up of the nearsighted-corrected patients, 86 percent of eyes in group one, 85 percent of group two, and 100 percent of group three had 20/30 or better visual acuity without glasses. In all groups, there was 20/40 or better visual acuity for 91 to 100 percent of patients.

For farsighted patients, 80 to 84 percent of all groups had 20/30 or better visual acuity at final follow-up, with 91 to 97 percent of all groups achieving 20/40 or better uncorrected vision. There was no statistical significant difference in final visual acuity between the different age groups.

Another challenge for older patients is difficulty with near vision after LASIK due to the loss of the ability to accommodate (presbyopia), Azar said. “As we age, we lose some elasticity of the lens of the eyes, making it impossible to maintain a clear image as objects are moved closer,” he said.

Many patients in the study opted for monovision, a strategy that compensates for presbyopia by correcting one eye for distance and the other eye for near vision.

“Patients who understand that monovision is a compromise that does not restore accommodation, but rather compensates for its loss, are most likely to adapt well to monovision,” Azar said.

“Although LASIK presents different challenges in the presbyopic age group, our study showed that for this age group, 40-69 years old, LASIK correction for near-sightedness and far-sightedness has reasonable safety, efficacy and predictability,” he concluded.

Ramon Ghanem and Jose de la Cruz Napoli, UIC ophthalmology and visual sciences, and Faisal Tobaigy and Leonard Ang, Harvard Medical School, also contributed to the study.

The study was supported by the National Institutes of Health and Research to Prevent Blindness Lew R. Wasserman Merit Award (Dr. Azar).

UIC ranks among the nation’s top 50 universities in federal research funding and is Chicago’s largest university with 25,000 students, 12,000 faculty and staff, 15 colleges and the state’s major public medical center. A hallmark of the campus is the Great Cities Commitment, through which UIC faculty, students and staff engage with community, corporate, foundation and government partners in hundreds of programs to improve the quality of life in metropolitan areas around the world.

Contact: Jeanne Galatzer-Levy

University of Illinois at Chicago

For many, celebrating the holidays calls for a champagne toast. But for some people popping a bottle of bubbly can be dangerous to your health.

“Eye injuries from flying champagne corks, especially around the holidays, are fairly common,” said Mark Melson, M.D., assistant professor of Ophthalmology and Visual Sciences at the Vanderbilt Eye Institute. “Champagne is part of the holidays, but opening the bottles properly might save some folks a trip to the emergency room or a visit to their eye doctor.

“It might be cool to have the cork pop and it’s exciting to have champagne gush from the bottle, but it’s not fun to suffer an eye injury that may prove to be devastating.”

Melson, who specializes in oculoplastic reconstructive surgery and neuro-ophthalmology, said the pressure from a champagne cork can be up to 3 times more than the pressure in a car’s tire. And champagne or sparkling wine corks can travel at speeds up to 50-60 miles per hour.

“That is a lot of force to the eye,” said Melson. “The damage can range from corneal abrasions to retinal detachment.

The best advice if someone does suffer an eye injury is to seek medical attention immediately. Do not manipulate the eye in any way.”

Those suffering from eye-related cork injuries might experience severe eye pain, discharge of fluid from the eye, loss of vision, flashes of light, floaters or specs in the eye as well as the feeling that a curtain or shadow is covering their vision.

Melson, along with the American Academy of Ophthalmology, suggests the following tips for proper champagne opening:

— Make sure the bottle of bubbly is chilled. If left warm the pressure is more likely to build.

— Don’t shake the bottle. This only increases the speed of the cork upon opening.

— Place a towel over the top of the bottle to provide an additional shield.

— Keep the bottle tilted at a 45-degree angle, pointing away from people.

— Hold the cork while twisting the bottle to break the seal. Keep your hand over the cork.

— Never use a corkscrew to open a bottle of champagne. It will only serve as a larger, more dangerous projectile.

“Often times, people have a delayed response because of impaired judgment,” said Melson. “And if treated in an appropriate fashion, we can prevent vision loss and permanent eye damage.

“I would recommend that people be as responsible as possible and just think about what you are doing before popping the cork. It’s one thing for the cork to hit the ceiling, but you can’t always control where that cork goes.”

Source: Vanderbilt University Medical Center

WHAT: In a new study from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, scientists describe successfully mutating specific genes of Chlamydia bacteria, which cause the most common sexually transmitted infection in the United States as well as a type of blindness common in developing nations. The procedure they used will help advance scientists’ understanding of how these bacteria cause human disease and expedite the development of new strategies to prevent and control these infections.

The advance could end decades of frustration for scientists who until now have been unable to manipulate Chlamydia genes in the laboratory, inhibiting research progress in the field.

Traditionally, gene manipulation involves directly introducing foreign DNA into bacteria. But Chlamydia bacteria live inside cells where they are protected from foreign DNA by a series of cellular and bacterial membranes. Therefore, more complicated and indirect approaches were applied to mutate Chlamydia genes.

The procedure, called Targeting Induced Local Lesions in Genomes (TILLING), has been used for years in plant genetics but is new to bacterial genetics. In their study, NIAID scientists used TILLING to successfully change the function of a specific Chlamydia gene. After creating a library of chemically mutated Chlamydia bacteria, they looked for mutations in a specific target gene. The analysis yielded a mutant with a single genetic change in the target gene; that change both inactivated the gene and greatly weakened the ability of the organism to survive in laboratory-grown human cells.

According to the study authors, TILLING may now be used to reveal the unknown function of hundreds of other Chlamydia genes in an effort to better understand these infections and develop new ways to treat and prevent them.

Chlamydia diseases include both sexually transmitted infections, which can result in pelvic inflammatory disease that can cause infertility in women, and trachoma, which can cause blindness and is common in developing nations. More than 1.2 million Chlamydia infections were reported to the U.S. Centers for Disease Control and Prevention in 2009. The World Health Organization estimates that more than 140 million persons have trachoma in regions of Africa, the Middle East, Central and Southeast Asia and Latin America.

Notes:

ARTICLE: L Kari et al. Generation of targeted Chlamydia trachomatis null mutants. Proceedings of the National Academy of Sciences. DOI: 10.1073/PNAS.1102229108 (2011).

WHO: Harlan Caldwell, Ph.D., chief of the Laboratory of Intracellular Parasites.

Source:
Ken Pekoc
NIH/National Institute of Allergy and Infectious Diseases

People suffering from a type of connective tissue disease characterized by inflammation of arteries in the head are three times more likely to experience blindness, new Geisinger research shows.

In a study published in a recent edition of the Journal of Clinical Pathology, Geisinger researchers examined a disorder known as temporal arteritis. In this disease, arteries swell and restrict blood flow to the brain.

Temporal arteritis can cause headaches, jaw soreness and flu-like symptoms. Untreated, the disease can lead to blindness or stroke. The average age for disease onset is 70.

Giant cells, which are white blood cells that destroy bacteria, are often found in patients with the disease. The Geisinger study found that patients with giant cells are far more prone to blindness compared to patients without these cells.

The study also found that patients with giant cells are three times more likely to experience Polymyalgia rheumatica, an inflammatory disorder that causes muscle aches and stiffness primarily in the arms, thighs and neck.

“We need to learn more about how these giant cells work so we can limit the effects of this disease, which can cause significant problems if ignored,” said Geisinger rheumatologist and lead study author Thomas Harrington, MD.

About Geisinger Health System

Founded in 1915, Geisinger Health System (Danville, PA) is one of the nation’s largest integrated health services organizations. Serving more than two million residents throughout central and northeastern Pennsylvania, the physician-led organization is at the forefront of the country’s rapidly emerging electronic health records movement. Geisinger is comprised of two medical center campuses, three hospitals, a 720-member group practice, a not-for-profit health insurance company and the Geisinger Center for Health Research dedicated to creating innovative new models for patient care, satisfaction and clinical outcomes. For more information, visit geisinger

Geisinger Health System
100 N. Academy Ave.
Danville, PA
United States
geisinger

Imagine a single pair of glasses with lenses that can be transparent or dark, and in shades of yellow, green or purple, all on command. A new lens with chameleon powers promises to dramatically improve sunglasses’ function.

Shades that can be controlled at the touch of a button would interest athletes, construction workers and anyone with sensitive eyes. The glasses are made possible by a new material uniquely suited to the task: a low-cost sheet that changes color and shade using almost no power. Prototype “smart” glasses were presented recently in Chicago at the American Chemical Society’s 233rd national meeting.

“These lenses are more active, more intelligent, than today’s sunglasses” said Chunye Xu, research assistant professor of mechanical engineering at the University of Washington. “But because of the materials we’re using we don’t think the price is going to be very different.”

Motorcyclists, skiers or mountain bikers might be in the shade one moment and pop into bright sunlight an instant later. Some high-end sunglasses already let athletes adjust to such changing conditions by swapping out lenses. But the new shades, which take from one to two seconds to transition, allow a much quicker switch. Current lens choices don’t simply include different levels of shading, but also different colors, such as yellow lenses, said to enhance contrasts and improve depth perception, or rose-colored glasses, which brighten low-light scenes. The new glasses would offer an endless range of options on one accessory.

Doctors already are recommending sunglasses that darken in response to the lighting conditions, known as photochromic lenses. These use incoming UV rays to trigger a chemical reaction that darkens the lens, but users can’t adjust the shade. Also, the lenses may stay bright under strong midday light or get too dark in low-level evening light due to the angle of incoming rays. And photochromic lenses have the drawback that when behind a UV-protected surface, such as a car’s window, the glasses won’t change color. Adjustable lenses would avoid that problem.

Researchers made the glasses using electrochromic materials that change transparency depending on the electric current. Many groups, including the UW, are developing such materials for so-called “smart windows” that could soon be used in energy-efficient homes and offices. Most smart windows use liquid-crystal technology or inorganic oxides. Those materials are expensive to produce and require a constant or frequent injection of power to hold their tint. The UW glasses are based on a new type of smart window using organic, rather than inorganic, oxides. These are cheaper to manufacture and require less power.

The prototype glasses are powered by a watch battery that attaches to the glasses frame, and the wearer spins a tiny dial on the arm of the glasses to change color or shade. The lenses were created by sandwiching a gel between two layers of electrochromic material. Applying a small voltage moves charged particles from one layer to another, and changes the transparency. Once the glasses are a certain tint they will stay that way without power for about 30 days. A single watch battery is able to power thousands of transitions, Xu said.

Organic molecules allowed the researchers to create colored lenses.

“In organic materials, the elements are simple but the structure is much more complicated,” Xu said. “We can add more branches to this structure and tune in colors.”

The prototype glasses change from dark blue to light blue. Xu and her colleagues have developed other adjustable lenses in red and yellow. In the future, they will layer sheets to create a range of colors in a single pair of shades.

“These are a little homemade,” Xu said of the prototype, a modified pair of lab goggles. She plans to incorporate the lenses in more fashionable frames. Xu’s group has a number of patents filed on the technology and is exploring options for commercialization. It will be a few years until these sunglasses show up on store shelves.

This research was funded by the UW’s Technology Gap Innovation Fund. Collaborators on the project are professor of mechanical engineering Minoru Taya and doctoral student Chao Ma.

Contact: Hannah Hickey
University of Washington

In an effort to combat one of the
main causes of blindness around the globe, the World Glaucoma Association
and the World Glaucoma Patient Organization have announced the first annual
World Glaucoma Day, to be observed on March 6, 2008. The day will be marked
by awareness and educational events organized by glaucoma institutions and
local patient support groups worldwide, as listed on wgday. As well
as striking the residents of developing countries at alarming rates,
glaucoma is the second leading cause of blindness in the United States and
the leading cause for African-Americans.

Known as “the sneak thief of sight,” glaucoma is a disease
characterized by gradual loss of vision resulting from death of the cells
in the eye which transmits visual images through the optic nerve to the
brain. As the optic nerve becomes increasingly damaged, permanent vision
loss and blindness can occur. Early detection is the key to treating and
halting the effects of glaucoma, but current worldwide estimates reveal
that more than half of glaucoma sufferers do not even realize they have the
disease.

“Because glaucoma strikes so silently and gradually, it is absolutely
crucial to educate people about the value of early detection,” said Robert
Ritch, MD, professor and chief of glaucoma services at The New York Eye and
Ear Infirmary, co-founder of the World Glaucoma Patient Association, and
member of the World Glaucoma Day committee for the World Glaucoma
Association. “For a disease that causes permanent blindness, it is truly
unacceptable that so many people remain unaware of its impact and
consequences. Individuals in our country need to be much more vigilant
about glaucoma, especially if they fall into one of the higher risk
groups.”

Persons at high risk for glaucoma should have their eyes examined for
the disease at least every two years by an eye care professional. In the
United States, at risk groups include: people with a family history of
glaucoma, African-Americans over the age of 40, people who are very
nearsighted or farsighted, and all persons over the age of 60.

In the early stages of glaucoma, there may be no symptoms and vision
can appear to be normal until a large amount has been lost. If undetected
and untreated, glaucoma will gradually claim all peripheral vision and move
on to cause total blindness. With early detection, glaucoma can be treated
with eye drops to lower intraocular pressure. Other standard methods of
treatment include laser and operative surgery. Treatment can usually halt
the disease, but it cannot reverse the damage that has been done. Glaucoma
can develop in one or both eyes.

About World Glaucoma Association:

The World Glaucoma Association is an independent professional global
organization dedicated to the overall improvement of glaucoma science and
care. Comprised of leading medical experts and institutions throughout the
world, the group’s overall goal is to optimize the quality of glaucoma
research and treatment through increased communication and cooperation
among international glaucoma societies, industries, and patient
organizations.

About World Glaucoma Patient Association:

The World Glaucoma Patient Association is an umbrella organization
which supports glaucoma associations and networks worldwide in their
efforts to educate and support their members so that all people with
glaucoma can understand and better manage their disease. The WGPA will
facilitate the establishment of new glaucoma support groups and coordinate
communication and cooperation between existing groups, in addition to
promoting international awareness of glaucoma as a cause of preventable
blindness.

World Glaucoma Day
wgday

There has been a recent questioning of the role of the limbal stem cell in corneal maintenance and the recent Association for Research in Vision and Ophthalmology (ARVO) meeting in Fort Lauderdale May 3 -7, 2009 saw some fairly hot debate son this topic. Professor Colin Green, University of Auckland, New Zealand reviews an interesting series of sessions for The Society for Clinical Ophthalmology.

The almost universally accepted “X,Y,Z” model for the natural turnover of corneal epithelial cells arose from the brief two page hypothesis of Thoft and Friend published in 1983 (Invest Ophthalmol Vis Sci. 1983;24:1442-3). Superficial cells are said to shed from the corneal surface by constant desquamation (Z component) and replaced from a population of stem cells which reside in the basal limbal region and continue to cycle slowly throughout life. Their daughter cells migrate centripetally (Y component) into the basal layer of the corneal epithelium and differentiate into upper layers of the cornea (X component) to become post-mitotic cells. The “X, Y, Z” hypothesis has been widely accepted and combined with the general belief that corneal epithelial stem cells reside in a highly specialised and protected limbal niche.

Recently Fran?�ois Majo and colleagues (Nature. 2008;456:250-4) suggested instead that oligopotent stem cells are distributed throughout the mammalian ocular surface and Chang et al. (Invest Ophthalmol Vis Sci. 2008;49:5279-86) have shown that the central human cornea expresses stem cell markers and is quite capable of healing after laser ablation in an ex vivo model.

Presentations at the recent ARVO meeting (May 3 -7) were set to be controversial and both poster and workshops sessions saw lively debate.

The full article can be accessed through the Society for Clinical Ophthalmology’s website, click here.

The Society welcomes submissins and comments from eye care practitioners across all specialities. If you were at ARVO, we are particularly keen to hear from you.

Source
Society for Clinical Ophthalmology

In macular degeneration, the most common form of adult blindness, patients progressively lose vision in the center of their visual field, thereby depriving the corresponding part of the visual cortex of input. Previously, researchers discovered that the deprived neurons begin responding to visual input from another spot on the retina – evidence of plasticity in the adult cortex.

Just how such plasticity occurred was unknown, but a new MIT study sheds light on the underlying neural mechanism.

“This study shows us one way that the brain changes when its inputs change. Neurons seem to ‘want’ to receive input: when their usual input disappears, they start responding to the next best thing,” said Nancy Kanwisher of the McGovern Institute for Brain Research at MIT and senior author of the study appearing in the March 4 issue of the Journal of Neuroscience.

“Our study shows that the changes we see in neural response in people with MD are probably driven by the lack of input to a population of neurons, not by a change in visual information processing strategy,” said Kanwisher, the Ellen Swallow Richards Professor of Cognitive Neuroscience in MIT’s Department of Brain and Cognitive Sciences.

Macular degeneration affects 1.75 million people in the United States alone. Loss of vision begins in the fovea of the retina – the central area providing high acuity vision that we use for reading and other visually demanding tasks. Patients typically compensate by using an adjacent patch of undamaged retina. This “preferred retinal locus” (PRL) is often below the blind region in the visual field, leading patients to roll their eyes upward to look at someone’s face, for example.

The visual cortex has a map of the visual field on the retina, and in macular degeneration the neurons mapping to the fovea no longer receive input. But several labs, including Kanwisher’s, previously found that the neurons in the visual cortex that once responded only to input from central vision begin responding to stimuli at the PRL. In other words, the visual map has reorganized.

“We wanted to know if the chronic, prior use of the PRL causes the cortical change that we had observed in the past, according to what we call the use-dependent hypothesis,” said first author Daniel D. Dilks, a postdoctoral fellow in the Kanwisher lab. “Or, do the deprived neurons respond to stimulation at any peripheral location, regardless of prior visual behavior, according to the use-independent hypothesis?”

The previous studies could not answer this question because they had only tested patients’ PRL. This new study tests both the PRL and another peripheral location, using functional magnetic resonance imaging (fMRI) to scan two macular degeneration patients who had no central vision, and consequently had a deprived central visual cortex.

Because patients habitually use the PRL like a new fovea, it could be that the deprived cortex might respond preferentially to this location.

But that is not what the researchers found. Instead, the deprived region responded equally to stimuli at both the preferred and nonpreferred locations.

This finding suggests that the long-term change in visual behavior is not driving the brain’s remapping. Instead, the brain changes appear to be a relatively passive response to visual deprivation.

“Macular degeneration is a great opportunity to learn more about plasticity in the adult cortex.” Kanwisher said. If scientists could one day develop technologies to replace the lost light-sensitive cells in the fovea, patients might be able to recover central vision since the neurons there are still alive and well.

Chris Baker of the Laboratory of Brain and Cognition (NIMH) and Eli Peli of the Schepens Eye Research Institute also contributed to this study, which was supported by the NIH, Kirschstein-NRSA, and Dr. and Mrs. Joseph Byrne.

Cathryn Delude, McGovern Institute

MIT

The prototypical member of the VEGF family of proteins, VEGF, has recently been shown to protect cells in the nervous system from death and degeneration. However, its clinical utility in this regard is limited, because it also induces blood vessel growth, a process known as angiogenesis. In a new study, Xuri Li and colleagues at the National Institutes of Health, Bethesda, have revealed that the VEGF family member VEGF-B acts as a potent inhibitor of murine retinal cell death while exerting minimal angiogenic effects.

In addition to inhibiting expression of cell-death-related genes, VEGF-B was shown to reduce the death of murine retinal cells in culture models of cellular injury and in mouse models of ocular neurodegenerative disorders. Furthermore, VEGF-B treatment inhibited brain cell death in a mouse model of stroke. As the concentration of VEGF-B required for retinal protection did not lead to angiogenesis in the mouse retina, the authors concluded that VEGF-B might provide a new therapeutic option for the treatment of neurodegenerative disease.

TITLE: VEGF-B inhibits apoptosis via VEGFR-1-mediated suppression of the expression of BH3-only protein genes in mice and rats

AUTHOR CONTACT:
Xuri Li
National Institutes of Health, Bethesda, Maryland, USA.

Source: Karen Honey

Journal of Clinical Investigation