Older Active People Fall Less Often With Single Lens Distance Glasses

Older individuals who wear multifocal glasses and who regularly take part in outdoor activities are less likely to suffer falls if they are provided with single lens distance glasses, say Australian researchers. However, the authors of a report which appeared in the British Medical Journal (BMJ) today warn that this strategy may not be appropriate for frailer people who spend more time indoors.

Presbyopia (a progressively reduced ability to focus on objects nearby) is the most common form of impaired vision in older individuals. To address for this condition, patients are either prescribed separate single lens glasses for distant and near vision or, for convenience, a single pair of multifocal (bifocal, trifocal, or progressive lens) glasses.

For tasks that require changes in focal length, such as driving, shopping and cooking, multifocal glasses have benefits. Their disadvantage is that they can impair balance and increase the risk of falls in older individuals.

So researchers in Sydney, Australia set out to test whether giving older people an additional pair of single lens distance glasses for wearing when outdoors or in unfamiliar settings would help to reduce falls.

They studied 606 people, either at least 80 years of age or at least 65 with a history of falls. All of them used multifocal glasses at least three times a week when walking outdoors and did not use single lens distance glasses.

Study participants were randomly selected into two groups, an intervention and a control group.

After an initial examination by an optometrist, 305 intervention participants were given a pair of single lens distance glasses for wearing outdoors and in unfamiliar settings, and were told how to use them. They were also shown how multifocal glasses can increase the risk of falls.

The control participants had the same optometrist examination as the intervention group, but were not prescribed single lens glasses and received no falls prevention advice.

They were monitored for 13 months. During that time, the total number of total falls in the intervention group was reduced by 8% compared with the control group. For those who went outdoors regularly, all falls – outside falls and injurious falls – dropped by approximately 40%.

However, outside falls increased significantly for those who spent more time inside.

The intervention did not influence physical activity or improve quality of life.

Based on these findings, the authors recommend that older people who engage in frequent outdoor activities should be provided with single lens distance glasses for outside use when they are prescribed their first pair of multifocal glasses. However, those who undertake little outdoor activity should use multifocal glasses for most activities, rather than using multiple pairs of glasses.

In an accompanying editorial, Professor John Campbell and team at the Dunedin School of Medicine in New Zealand say that correcting vision can help lower the likelihood of a fall, but that any changes should be introduced gradually in a planned manner so that an individual is not overwhelmed. They also recommend good communication between doctors and optometrists when considering vision, glasses and the risk of falls.

Research: “Effect on falls of providing single lens distance vision glasses to multifocal glasses wearers: VISIBLE randomised controlled trial”
Mark J Haran, Ian D Cameron, Rebecca Q Ivers, Judy M Simpson, Bonsan B Lee, Michael Tanzer, Mamta Porwal, Marcella M S Kwan, Connie Severino, Stephen R Lord
BMJ 2010;340:c2265
Published 25 May 2010, doi:10.1136/bmj.c2265

Editorial: “Poor vision and falls”
A John Campbell, Gordon Sanderson, M Clare Robertson
BMJ 2010;340:c2456
Published 25 May 2010, doi:10.1136/bmj.c2456

Meeting Of The Optical Society Of America: Restoring Sight, Advances In Fertility Treatments And More

Frontiers in Optics 2007 (FiO), the 91st Annual Meeting of the Optical Society of America, will be held from Sept. 16-20 in San Jose, Calif., alongside Laser Science XXIII, the annual meeting of the American Physical Society Division of Laser Science.

FiO RESEARCH HIGHLIGHTS

Following are a few of the many technical highlights to be discussed at the meeting:

* Restoring Sight, One Pixel at a Time

* Near-Infrared LIDAR Helps Pilots

* Better, Stronger, Faster: High-Throughput Sperm Sorting

* Detecting Malaria with Light

* Gigantic Photoresponse Can Speed Up Optical Switches for Faster Internet Speeds

* Explaining a 21st Century Version of Young’s Experiment

Restoring Sight, One Pixel at a Time

Researchers at the University of Southern California (USC) are developing a tiny camera for prosthetic systems that can be implanted directly into the human eye and connected to the retina, the part of the eye that converts visual information into electric signals that travel to the brain. Such an implantable camera would represent an important milestone in the ultimate goal of providing limited vision to those rendered blind by certain diseases, via a fully implantable retinal prosthetic device.

In both retinitis pigmentosa and age-related macular degeneration — two of the most common causes of vision loss — the photoreceptor layer of the retina is destroyed, but the inner layers remain largely intact, still capable of responding to incoming signals and transmitting output signals to the brain’s visual cortex via the optic nerve. The discovery several years ago that direct electrical stimulation of retinal nerve cells in blind test subjects produced some sense of vision led to the development of the first retinal prosthesis.

Current retinal prostheses are designed to be used with an external (extraocular) camera mounted in a pair of glasses — awkward because subjects must move their heads in order to scan the environment. The miniaturized prototype being developed by the USC team would be directly implantable and would allow for natural eye and head movements.

In order to optimize the design constraints for their ultra-miniature camera, the group performed a series of studies to determine the minimum requirements for vision-related tasks like object recognition, face recognition, navigation, and mobility. They found that surprisingly few pixels were required to achieve good results for many of those tasks: approximately 625 pixels in total, compared to more than a million for a typical computer display. They also found that in many cases blurring images — both before and after they were converted into pixels — resulted in significantly improved object recognition and tracking — even better for moving objects than for static ones.

Taken together, these findings have made it possible to substantially relax the once extremely stringent design requirements of key components of the intraocular camera, thereby reducing the prototype intraocular camera’s size and weight from an object the size of a Tylenol tablet down to an object that is now about one-third the size of a Tic-Tac. Early prototypes have been highly successful in initial tests, although human FDA trials are still at least two years out. (Paper FThT1, “Intraocular Camera for Retinal Prostheses: Design Constraints Based on Visual Psychophysics”)

Near-Infrared LIDAR Helps Pilots

Airline pilots will have more advance warning of potentially hazardous atmospheric conditions — such as icing — using a new near-infrared Light Detection and Ranging (LIDAR) system developed by scientists at RL Associates in Chester, Pa. The system, now in a prototype testing phase, will also provide better images in foggy, rainy or extremely hazy conditions, making it easier for pilots to take off and land in those conditions, thereby potentially reducing flight delays.

Right now, other experimental systems use visible green light to detect the different types of particles in the atmosphere. Most commercial planes, however, don’t have this kind of system, and flights are grounded rather than risk a foggy landing or misidentifying clouds of icy particles. The RL Associates LIDAR system, which could be quickly commercially deployed, is slated for testing in approximately 18 months.

LIDAR exploits the same basic principle as radar, using light waves instead of radio waves. Lasers use light at wavelengths much smaller than radio waves, so they are much better at detecting very small objects. LIDAR already is frequently used in atmospheric physics — but not on commercial planes — to measure the densities of various particles in the middle and upper atmospheres. According to Mary Ludwig of RL Associates, the system uses a laser light beam that is polarized, or has its electric field pointing in a specific direction. The system beams the polarized infrared light out, and then records the amount of polarization that returns to the sensors. Rain and fog return a less polarized signal, and metal and people return a more polarized signal. The data is then processed to form an image of the ground, or could be translated into verbal commands if needed.

The system can better detect different types of particles in the atmosphere, such as ice, supercooled liquid or just regular water vapor. It can also identify the difference between water vapor and other kinds of substances, such as metal or the human body. Ludwig says the RL Associates system is the first of its kind to use near-infrared. The system also employs a “range-gated detector” that is only turned on for very short periods of time when the return signal is expected. This leads to a vastly improved signal-to-noise ratio, resulting in better images, particularly in obscuring conditions such as fog or haze. (FThG4, “Near-Infrared LIDAR System for Hazard Detection and Mitigation Onboard Aircraft”)

Better, Stronger, Faster: High-Throughput Sperm Sorting

Researchers at the University of California, Irvine (UCI) and San Diego (UCSD), have developed a rapid new sorting technique for sperm using a laser trap that can separate stronger, faster sperm from slower sperm. Faster sperm are more likely to successfully fertilize an egg, so the technique could improve the chances of conception via in vitro fertilization by ensuring that only the fastest, strongest sperm are used. The technique could find wide application in animal husbandry and human fertility treatments.

UCI scientist Bing Shao and her colleagues at UCSD have developed a new laser-based technique that enables not only analysis of swimming speed, but on-the-spot sorting of more desirable faster from slower sperm. Shao’s team used special cone-shaped lenses called “axicons,” which, when combined with a standard lens and a laser, form a ring-shaped focus (an annular laser trap). Such an arrangement has been used for laser machining as well as for trapping atoms. The trap acts as a kind of “speed bump” for swimming sperm, depending on the power of the laser used: slower, weaker sperm below the threshold of the laser power being used will be slowed down, redirected, or stopped altogether in the trap, while faster, stronger sperm are hardly affected at all because their energies are above the critical threshold. The researchers used both human sperm and gorilla sperm in their experiments, the latter as a control, since gorilla sperm are slower and weaker than human sperm.

Since X sperm generally are heavier and swim slower, while Y sperm are lighter and swim faster, it is also possible to use this new technique to separate sperm carrying the gene for a female child from sperm carrying the gene for a male child to assist with gender selection. (Paper FWP4, “Annular Laser Trap: A Tool for High-Throughput Sperm Sorting and Analysis”)

Detecting Malaria with Light

It is now possible to analyze large tissue samples for signs of malaria with much greater detail and accuracy. To do this, scientists at the University of Waterloo in Ontario, Canada and Spain’s University of Murcia used a Macroscope — a patented technology developed by Biomedical Photometrics Inc., which enables imaging of much larger tissue samples at a very high resolution — in this case tissue infected with malaria. Using their new patented method and the Macroscope, the researchers measured tell-tale changes in the polarization of light reflecting off a sample of infected tissue.

The malaria parasite changes the polarization of light and this has been exploited to measure population density in blood samples using polarimetry. Melanie Campbell, a researcher at the University of Waterloo and immediate past president of the Canadian Association of Physicists, and her colleagues have extended this approach to analyzing tissue samples. They looked at both infected and normal tissue in their experiments, and used a confocal laser scanning Macroscope to measure changes in polarization and highlight the levels of malaria parasites in the tissue samples. By using the Macroscope to image larger tissue samples at higher resolutions, the severity of infection by the malaria parasite may be accurately quantified.

The technique allows large areas to be imaged in a single scan as opposed to the smaller field available with a traditional microscope. This avoids time-consuming “stitching” of a large number of smaller images and increases data accuracy. Not only could this new approach improve the assessment of the severity of cases of malaria, but it could be extended to assessing different tissues infected with other kinds of biological abnormalities — possibly including proteins associated with Alzheimer’s disease — that also interact with polarized light. (Paper FThK1, “Confocal Polarimetry Measurements of Tissue Infected with Malaria”)

Gigantic Photoresponse Can Speed Up Optical Switches for Faster Internet Speeds New research shows that an ultrafast, ultralarge change in reflectivity can be brought about with femtolasers, those that deliver pulses just quadrillionths of a second in length. Dramatic reflectivity changes will be useful in bringing about direct ultrafast optical-to-optical switches for quicker Internet data transfer, faster computers and other applications. In a recent experiment, femtosecond laser pulses falling on an organic salt target momentarily changed the material from an insulator (a bad reflector of light) to a semi-metal (a good reflector of light). The change in reflectivity this large — more than 100% — has never been achieved before in a photonic material; photo-induced changes are usually more like a few percent. Researchers found that the laser pulse required doesn’t even have to be particularly intense to cause the change.

This “gigantic photoresponse” work began as a Tokyo Institute of Technology – Kyoto University collaboration but now also includes the U.S.’ Lawrence Berkeley Laboratory and the U.K.’s Oxford University. The new advance is that the change in reflectivity can be brought about in tens of femtoseconds rather than 150 femtoseconds. The new results will be reported at the meeting by Jiro Itatani, who has a joint appointment at Lawrence Berkeley Laboratory and the Japan Science and Technology Agency. (Paper FWA2, “Ultrafast Gigantic Photo-Response in Organic Salt (EDO-TTF)2PF6 Initiated by 20-fs Laser Pulses”)

Explaining a 21st Century Version of Young’s Experiment

When light strikes a metallic array of tiny openings, smaller than the wavelength of the light itself, interesting entities known as plasmons may be created. An electromagnetic phenomenon like light itself, the plasmons are waves of electrons that move on the surface of a material like ripples on a pond, but they can oscillate back and forth at the frequency of the incoming light. Like water ripples on a pond surface, plasmons travel in the plane of the metal but with a wavelength smaller, sometimes considerably smaller, than the original light.

Just as light can interact with plasmons, these plasmons traveling between the openings, or “apertures,” can be reconstituted as light at the apertures. The overall effect is that “large” light can pass through tiny holes.

Scientists are now running experiments to find how the plasmons appear and reform into light by passing light through apertures in various ways. One way is to do the plasmon version of a common high school physics lab experiment: passing waves through two slits, and watching how they interact on the other side. In a high school lab, the waves would be made of water; in the latest experiments, physicists examined the intermediary step in which the plasmons are created near the aperture, pass through, and then reform into a light wave on the other side. This kind of test results in interference patterns from which the coherence altering influence of surface plasmons can be deduced.

C.H. Gan of the University of North Carolina (UNC), Charlotte will report on some new theoretical predictions about the coherence properties of light transmitted through the slits. The theoretical predictions were done by computer simulations of the plasmons’ action. The detailed simulations, done with collaborators Greg Gbur of UNC Charlotte and T.D. Visser of the Free University of Amsterdam, show how surface plasmons traveling between the apertures result in a correlation of the light fields emitted from the apertures. Gan shows how this effect can be tuned (such as by varying the size or spacing of the slits). This tunability in turn has the potential to be exploited in new, potentially high-resolution, high-quality forms of coherence-related imaging. (Paper FTuS3, “Surface Plasmons in Young’s Experiment Modulate the Spatial Coherence of Light”)

PLENARY SESSION: NANOPHOTONICS AND OPTICAL FREQUENCY COMBS

At the plenary and awards session, two speakers will present topics that span numerous realms in cutting-edge optics. Nobel Laureate John L. Hall contributed significantly to the development of the laser, helping to take it from a laboratory curiosity to one of the fundamental tools of modern science. In his talk, “The Optical Frequency Comb: A Remarkable Tool with Many Uses,” he will describe a recent measurement tool that can verify assumptions involving miniscule distances within atoms yet also potentially help detect Earth-like planets outside our solar system. Dr. Hall is a senior fellow emeritus of the National Institute of Standards and Technology (NIST) and an adjoint fellow of JILA (formerly the Joint Institute for Laboratory Astrophysics).

The second talk, “Nanophotonics: From Photonic Crystals to Plasmonics,” will be presented by Eli Yablonovitch of University of California, Berkeley. The natural world is filled with crystals, structures made of building blocks arranged in a repeating pattern that interact with electron waves. In his talk, Yablonovitch will start by discussing photonic crystals, artificial, multidimensional, periodic structures that are intended for electromagnetic waves. Such nanophotonic structures are now being designed and used in electronic chips, silicon-on-insulator structures that can reduce current leakage and power consumption in state-of-the-art computer chips. Miniaturizing the structures further will take us toward nanoplasmonics, metallic-wired electrical circuits running at optical frequencies.

ABOUT OSA
Uniting more than 70,000 professionals from 134 countries, the Optical Society of America (OSA) brings together the global optics community through its programs and initiatives. Since 1916 OSA has worked to advance the common interests of the field, providing educational resources to the scientists, engineers and business leaders who work in the field by promoting the science of light and the advanced technologies made possible by optics and photonics. OSA publications, events, technical groups and programs foster optics knowledge and scientific collaboration among all those with an interest in optics and photonics. For more information, visit osa/.

Source: Colleen Morrison

Optical Society of America

Earlier Introduction To Long Cane Benefits Visually Impaired Children

AER Journal When “T” started kindergarten, she was an independent, confident child who was fully able to move about in her new environment even though she was the only visually impaired child in her school and used a long cane. T was born in 2003 with Leber’s congenital amaurosis, a rare inherited eye disease, and has no light perception. She was introduced to the long cane at the early age of 14 months to foster her independence of mobility and functioning.

“Early Long Cane Use: A Case Study” appears in the Winter 2010 issue of AER Journal: Research and Practice in Visual Impairment and Blindness. The article discusses the philosophy behind the early introduction of the long cane and follows an Australian child’s orientation and mobility training from the age of 14 months to the age of 4 years, 6 months.

Like any toddler, T’s first explorations with her long cane included feeling it, chewing it, and banging it around. To make it an essential part of her daily life, it was named “Tinkerbell” and accompanied T and her family wherever they went. Gradually, rules about using the long cane were introduced, including keeping it on the ground, grasping it with the index finger pointed down, and using an appropriate arc width.

T’s orientation and mobility training during this time emphasized fun and exploration. She was encouraged, but not required, to use the long cane. Over time it became automatic for her to reach for it in order to travel independently.

The training included exposure to other visually impaired children who use a long cane, allowing older children to serve as role models for the younger ones. T attended Braille Nest, a weekly group program for visually impaired children who are enrolled in their local schools, where they are generally the only child with such an impairment.

An essential part of T’s success and all such early childhood orientation and mobility programs is collaboration among those teaching the child. The orientation and mobility specialists, early childhood teachers, parents, and classroom teachers were made aware of techniques and terminology and helped to reinforce them. T and other children like her are able to start school independently with a set of positive skills already in place.

About AER Journal: Research and Practice in Visual Impairment and Blindness

AER Journal: Research and Practice in Visual Impairment and Blindness is a quarterly journal in the field of education and rehabilitation of persons of all ages with low vision or blindness. The journal features excellent research that can be applied in a practical setting as well as best practice examples that contain enough detail to be implemented by other practitioners. The journal reports on informative and helpful practices, research findings, professional experiences, experiments, and controversial issues. It is the official publication of the Association for Education and Rehabilitation of the Blind and Visually Impaired (AER).

Source: Allen Press Publishing Services

Community Health Centers Offer A Vision For Quality Eye Care

For more than 55 years Chicago resident Ronald Seals has laced up his roller skates hitting the hard wood to perform spins, dances and the most difficult move of all, the “Big Wheel” — all with his family skating by his side. Seals’ eight wheels have rolled with four generations including his mother and father, ten brothers and sisters, children and grandchildren. The tradition almost came to a screeching halt when Seals nearly lost his vision.

“I was shocked to learn that I had glaucoma. I wasn’t experiencing any symptoms, I never thought I had to worry about vision problems,” said Seals.

Seals is just one of the 50 million Americans who are uninsured or underinsured and are often forced to approach eye care as a luxury rather than a necessity. The price of medication and the cost of appointments deter patients from getting regular eye exams, which can result in irreversible vision loss if problems are left undetected and untreated. It is this reality that set an agenda for Near North Health Services Corporation, a non-profit community based health center to offer ophthalmology services where patients can receive eye exams at little or no cost.

“Many eye diseases are silent and progressive. Without periodic exams and proper treatment many people are at risk of vision loss or even blindness,” said Paul Bryar, MD, who is an ophthalmologist at Northwestern Memorial Hospital and director of the Ophthalmology Suite at Winfield Moody Health Center, one of Near North’s sites. “The goal of creating an Ophthalmology Suite was to reduce the barriers uninsured patients like Seals are experiencing in accessing eye care while also providing primary care and education.”

Being uninsured, Seals was unable to play a proactive role in his healthcare. “I never went to see the doctor. I couldn’t afford preventive care, and frankly, I felt fine,” Seals explained. While at Winfield Moody with his mother, Seals learned of the Ophthalmology Suite and decided to take advantage of the services by receiving a much needed eye-exam.

Bryar diagnosed Seals with glaucoma and immediately put him on a treatment plan ultimately saving his vision and his future of roller skating with his family. Bryar considers Seals a success story and a prime example of the importance of routine eye screening even for patients that fall outside of the high risk groups. “If Ron hadn’t come in for an exam, his disease could have progressed causing blindness. Glaucoma needs to be detected early in order for treatment to be effective,” added Bryar, who is also an associate professor of ophthalmology at Northwestern University Feinberg School of Medicine.

Chronic diseases such as diabetes, HIV, hypertension and stroke can cause vision problems. Those most commonly associated are glaucoma, cataracts and diabetic eye disease, which often have no symptoms and are difficult to self-diagnose, underscoring the importance of annual dilated eye exams.

As many as one third of the adult patients at Winfield Moody have diabetes which is the leading cause of blindness in adults under the age of 70; in prior years, many of these patients have not had access to adequate eye care. “One of our primary goals in the Ophthalmology Suite is to make sure that every patient with diabetes has a yearly eye exam,” said Bryar.

In addition to the Ophthalmology Suite at Winfield Moody, Northwestern Memorial ophthalmologists support clinics at Near North’s Komed Holman Health Center located in the South Side of Chicago, and last year opened a new optometry suite at Erie Family Health Center, another federally qualified health center that serves Chicago’s Humboldt Park neighborhood. The suites offer accessible eye care for thousands of Chicago’s low-income patients by providing comprehensive eye testing and treatment, including vision screening, dilated exams and glaucoma testing performed by an optometrist and an ophthalmologist.

“Northwestern Memorial has a longstanding relationship with Near North and Erie Family Health that were built on the principles of providing quality care to underinsured and uninsured patients in the Chicago community,” said Daniel Derman, MD, vice president of operations at Northwestern Memorial. “Through our collaboration, we look forward to offering continued financial and strategic program support to ensure patients have access to the care they need.”

“I feel so blessed that I am able to continue skating with my family, without that I would be lost,” added Seals.

Source: Northwestern Memorial Hospital

Embryonic Stem Cells To Treat Macular Degeneration Trial Approved By FDA

The first trial has been approved by the FDA using retinal cells derived from human embryonic stem cells to treat patients with SMD (Stargardt’s Macula Dystrophy), a common form of macular degeneration that affects young people. The FDA had a clinical hold on the commencement of Phase I/II clinical trial at multiple centers – this has now been lifted, the company Advanced Cell Technologies announced today.

Stargardt’s Macular Dystrophy, sometimes called Juvenile Macular Dystrophy, is an inherited condition in which the macula – the central area of the retina – is affected. The macula is responsible for what we see directly in front of us, the vision required for detailed activities, such as writing and reading, and the detection and appreciation of color. In SMD, which tends to first appear when the patient is aged between ten and twenty years, some of the macula cells stop working, resulting in problems with central vision, detailed vision, and possibly color perception – specifically, the cells of the pigmented layer of the retina, called the retinal pigment epithelium (RPE), deteriorate and die. It is a progressive disease which eventually leads to blindness.

Dr. Robert Lanza, Chief Scientific Officer, Advanced Cell Technologies, said:
“There is currently no treatment for Stargardt’s disease. Using stem cells, we can generate a virtually unlimited supply of healthy RPE cells, which are the first cells to die off in SMD and other forms of macular degeneration. We’ve tested these cells in animal models of eye disease. In rats, we’ve seen 100% improvement in visual performance over untreated animals without any adverse effects. Our studies showed that the cells were capable of extensive rescue of photoreceptors in animals that otherwise would have gone blind. Near-normal function was also achieved in a mouse model of Stargardt’s disease. We hope to see a similar benefit in patients with various forms of macular degeneration.”
The Prospective Phase I/II trial will be an open-label study with the main aim of determining the safety and tolerability of the retinal pigment epithelium cells following sub-retinal transplantation on twelve patients with advanced Stargardt’s Macular Dystrophy.

Because the FDA granted the RPE cells Orphan Drug designation, Advanced Cell Technologies will also be eligible for tax credits, grant funding, accelerated approval, and marketing exclusivity up to seven years after approval.

Raymond Lund, Ph.D., a respected retinal cell physiology and vision restoration expert, said:
“The study results of ACT’s RPE cells implanted in the various animal models of macular degeneration was phenomenal. If ACT observes even a fraction of that benefit in humans, it will be nothing short of a home run.”
William M. Caldwell IV, Chairman and CEO of Advanced Cell Technologies, said:
“Initiating our macular degeneration clinical trial represents a significant milestone in the progress of developing human embryonic stem cell-based therapies aimed at large worldwide markets. I think generations will look back at this time as one of the most exciting in the history of medicine. With the initiation of this clinical trial, and that of Geron’s earlier this fall, the field of regenerative medicine is poised to take embryonic stem cell therapies from the realm of nebulous potential to that of tangible and real treatments that will make a significant difference in the lives of millions of people worldwide. This is truly a ‘game changer’ for the medical community.”
Thirty million people in Europe and the USA are estimated to be affected by macular degeneration. This $25 to 30 billion global market has not yet been properly addressed, the company explains. About 1 in every ten individuals aged 66 to 74 has symptoms of macular degeneration, most of them in the dry form of AMD, a condition for which there is no current treatment. 30% of 75 to 85 year-olds have symptoms.

Edmund Mickunas, Vice President of Regulatory, Advanced Cell Technology, said:
“These patient numbers are staggering in size, and when the impact on health and quality-of-life is considered in that context, macular degeneration represents one of the more significant unmet medical needs in our society. With the momentum of this Stargardt’s trial, and the unique experience we have gained as one of the few companies in the world having succeeded in taking an hESC program into the clinic, we are preparing to extend our lead with an IND in the use for treating age-related macular degeneration, as well as filing to begin clinical trials in Europe, in the very near future.”
Source: Advanced Cell Technology

Visual Perception And Attention Can Be Changed By Passive Stimulation

What was previously known from animal studies has, for the first time, been demonstrated for humans too. “The findings open new perspectives in the intervention and treatment of visual perceptual disorders, because the changes can be induced quite simply” said Dr. Christian Beste of the RUB Institute of Cognitive Neuroscience.

New perspectives in learning

“The gold standard to achieve a lasting change in behaviour and perception is by means of training and practice, which intensively stimulates the brain” explains PD Dr. Hubert Dinse from the RUB’s Institute of Neuroinformatics. “In case of learning through passive stimulation, training is replaced by stimulus exposure, but in order to be effective, it has to conform to specially adapted timing.” As the scientists have shown, visual perception is impaired after slow visual stimulation, whereas rapid stimulation leads to improved perception. “In this way, we can determine the direction of learning processes by simple selection of the stimulation frequency” Dinse sums up. The changes were remarkably stable, as the effects remained unchanged for ten days.

From animal models to humans

From animal experiments it is known that stimulating nerve cells electrically with either high or low frequency strengthens or weakens connections between cells, which is the foundation of learning and plasticity. In humans, changes in behaviour and perception are usually evoked by prolonged practice. The findings of the Bochum and Dortmund neuroscientists suggest that instead of training or electrically stimulating cells, selective behavioural changes can be evoked in humans by using equivalently timed visual stimulation of only forty minutes duration.

Making stimuli stronger or weaker

“Whether a sensory event is able to attract attention depends on its strength” states Beste. According to some models, different sensory events compete with each other and only the strongest influence our behaviour. Using passive visual stimulation, depending on the frequency, stimuli can be weakened or strengthened, thus changing the attentional process.

Bibliographic record

Beste C, Wascher E, G??nt??rk??n O, Dinse, H (2011) Improvement and Impairment of Visually Guided Behavior through LTP- and LTD-like Exposure-Based Visual Learning. Current Biology. doi:10.1016/j.cub.2011.03.065

Source:
Dr. Christian Beste

Ruhr-University Bochum

HRH The Countess Of Wessex Visits Bangladesh To Witness Fight Against Avoidable Blindness

HRH The Countess of Wessex is visiting Dhaka region of Bangladesh from 23-25 March in her capacity as Patron of Vision 2020: The Right To Sight, the global initiative for the elimination of avoidable blindness.

The Countess is in Bangladesh as a guest of the disability agency Sightsavers International and Standard Chartered Bank. Over the course of three days, she will be looking at the progress that is being made in Dhaka with regards to delivering eye care services to some of the hardest to access communities in the city. She will also meet with Professor Ruhul Haque, Minister of Health and Family Welfare, as well as leading representatives from international eye care agencies operating in Bangladesh.

Through its community investment programme Seeing Is Believing, Standard Chartered Bank has pledged to continue its existing partnership with Sightsavers to strengthen eye care facilities in Bangladesh by investing USD one million over five years in the Dhaka Urban Comprehensive Eye Care project (DUCEC). Initiated in 2003 and driven by the Bank’s employees, Seeing is Believing is helping to tackle avoidable blindness, 90 per cent of which is found in the developing world where the bank’s business is rooted.

The services provided as a result of Seeing Is Believing will be comprehensive, delivering community eye health education and awareness-raising, together with a range of interventions, from spectacle provision, to surgery according to need. The services will also be sustainable, designed to support marginalised and excluded populations both now and in the future.

Joanna Conlon, programme manager for Seeing Is Believing at Standard Chartered Bank, said: “Avoidable blindness is a major problem in many of our markets and it is not just a health issue; it is also an economic issue, depriving those affected of education and a job, and often rendering them economically dependent. The consequences are highly detrimental to families and communities, deprived of the productivity of both the cared for and the carers.”

An estimated 750,000 people are blind in the country yet 80% of all blindness is due to cataract which can be treated easily and cost-effectively. There are 150,000 new cataract cases each year, creating a huge backlog of untreated cases which Seeing Is Believing, Sightsavers and partners are working to address. Refractive error is the second leading cause of blindness in Bangladesh – two million people have low vision and six million could be helped through vision correction such as something as simple as a pair of glasses. Additionally, there are 40,000 children who are blind, with somewhere in the region of 1000 new cases each year.

Seeing Is Believing’s implementing partner Sightsavers International has been working in Bangladesh with local partners since 1973 to bring eye care within reach of the poorest communities, and has helped to develop services for people who are irreversibly blind, as well as ensuring children who are visually impaired have access to a quality education.

Dr Wahidul Islam, Sightsavers’ director in Bangladesh, commented: “Blindness and poverty are inextricably linked. People with disabilities are more likely to be unemployed and tend to have fewer opportunities to access a quality education. We hope that the visit by HRH The Countess of Wessex will inspire the Government of Bangladesh and all key stakeholders to redouble their efforts when it comes to ensuring eye care for all.”

HRH The Countess of Wessex was born Sophie Rhys-Jones in 1965 in Oxford, UK. After working in public relations for over a decade, Miss Rhys-Jones married The Earl of Wessex in 1999. As The Countess of Wessex, she acts in support of her husband in his roles, and undertakes public duties for a large number of her own charities. She is particularly involved with charities relating to children, disabilities and communication problems and is a Global Ambassador for the International Agency for the Prevention of Blindness (IAPB), the leading umbrella organization for NGOs working in the field of eyecare. Together with the World Health Organization, IAPB launched the ‘VISION 2020: The Right to Sight’ global initiative to eliminate avoidable blindness by 2020.

Seeing is Believing (SiB) is a global initiative to help tackle avoidable blindness. SiB is a partnership between Standard Chartered Bank and the International Agency for Prevention of Blindness. As part of its “New Vision,” Seeing Is Believing aims to invest USD 20 million by 2012 to provide sustainable eye services for 20 million people in disadvantaged areas of 20 cities around the globe including Dhaka where services will be implemented by Sightsavers International together with their local partners. seeingisbelieving

Sightsavers International is an international agency that works in more than 30 developing countries to prevent blindness, restore sight and advocate for social inclusion and equal rights for people who are blind and visually impaired. Since 1950, Sightsavers has restored sight to more than 5.65 million people and treated over 100 million more. sightsavers

Sightsavers International

MIT Refines Optical ‘Lab On A Chip’ – Live-Animal Nerve Regeneration Study Gets A Boost

An MIT team has improved upon its landmark technology
reported last year in which the researchers used a fingernail-sized lab on
a chip to image, perform surgery on and sort tiny worms to study nerve
regeneration.

The team has found a unique way to immobilize the animals while they are
still awake for several minutes with unprecedented stability, which then
allowed the researchers to conduct fast, detailed three-dimensional
imaging and to perform high-resolution laser nanosurgery on the animals.

The advance, which builds on a technology first reported last year, could
ultimately help researchers better understand the genetic underpinnings of
regeneration and degeneration in the nervous system-not just in the worm
but in more complex organisms including humans. That, in turn, could help
in treatments of neural injuries and diseases such as Parkinson’s and
Alzheimer’s.

Led by Mehmet Fatih Yanik, MIT assistant professor of electrical
engineering and computer science, the team reported its latest work in the
April 2 advanced online issue of the journal Lab on a Chip. The work
involves the C. elegans worm, one of the tiniest multi-cellular organisms
known. Smaller than a human hair, the worm is considered a key model for
investigating a variety of biological phenomena such as aging, fat
metabolism and neurological diseases.

Geneticists have been studying C. elegans since the 1960s, but the manual
processes they used to do so were painstaking and time-consuming. That
changed in a big way last year when Yanik and colleagues reported in the
Proceedings of the National Academy of Science that they had developed a
microfluidic chip to automate and accelerate research on the tiny worms.
Essentially, the tiny worms are flowed inside the chip, immobilized by
suction and imaged with a high-resolution microscope.

The research published this month goes one step further. Yanik and two
collaborators, lead authors Fei Zeng, a postdoctoral fellow in the
Research Laboratory of Electronics, and Christopher B. Rohde, a graduate
student in electrical engineering and computer science, said they were
able to render the animals motionless in the chip with an unprecedented
stability for several minutes instead of seconds. This then allowed them
not only to conduct three-dimensional imaging of the worms at the
sub-cellular resolution but also to reliably operate on the animals with a
high-precision surgery laser to study neural degeneration and regeneration
on the chip. Yanik’s team had previously demonstrated that neural
regeneration can be studied in C. elegans using femtosecond laser
micro-surgery.

“This new technology is allowing us to study the entire genome of the
animal in very short periods of time,” Yanik said. “We are currently
combining it with genetic and drug screens to study neural regeneration on
these animals.”

Yanik received the NIH Director’s Innovator Award last year for developing
the lab on a chip technology to screen whole animals and study neural
regeneration.

The research was funded by NIH Director’s New Innovator Award
(1-DP2-OD002989-01) and Packard Award in Engineering and Science, and
Merck & Co. Inc.

Greg Frost, MIT News Office

mit.edu

Study Finds Visually Impaired People Get Insulin Pen Dosages Right

Labels on the popular insulin pen used by people with diabetes warn against visually-impaired people using pens to measure out and administer their insulin dosage.

A Case Western Reserve University pilot study from the Frances Payne Bolton School of Nursing overturns that thinking, finding that visually impaired people actually did slightly better than their seeing peers, although the difference was not statistically significant.

Ann S. Williams, the lead investigator of the study, “A Comparison of Dosing Accuracy: Visually Impaired and Sighted People Using Insulin Pens,” speculates, based on observations of individuals in the study, that the reason behind the poor performance of certain individuals in the sighted group is that some glossed over important instructions about how to use the pen. In contrast, individuals with sight problems listened, step by step, to complete audio instructions before using the pen in the study.

Sixty people participated in the study. This is one of the first research projects on insulin dosage to include participants who are visually impaired.

According to the Centers for Disease Control and Prevention, 23.6 million people in the United States – 7.8% of the population – have diabetes. Among the 17.6 million with diagnosed diabetes, 3.6 million, or about 20 percent have visual impairment.

The results were published in the Journal of Diabetes Science and Technology. Besides the inherent importance of these results to visually impaired persons with diabetes, this study also demonstrates the importance of including people with disabilities in research.

CWRU has established the FIND Lab, a National Institutes of Nursing Research/National Institute of Health-funded center to promote Full Inclusion of Persons with Disabilities (FIND) in Research. It is part of the nursing school’s SMART Center, funded by the NIH to find ways to promote better self-management of an individual’s healthcare.

Although insulin pens are manufactured by a number of companies and have been on the market since the 1980s, Williams found no research literature available that supported the disclaimer that blind people cannot accurately use the insulin pens when they receive complete instructions in a format they can use.

In 2008, the National Federation for the Blind passed a resolution calling for removal of the disclaimer against the use by blind people.

“This resolution emphasized the real-world importance of rigorous investigation of the accuracy of insulin dosage by visually impaired people using non-visual techniques,” Williams reported.

As a diabetes educator, Williams knew visually impaired people were successfully using the pen with accuracy but needed the scientific research to support her observations.

During the 2009 National Federation for the Blind meeting in Detroit, Williams recruited 30 individuals who have vision problems that prevent them from reading printed instructions. They were given complete recorded instructions. She also enrolled 30 individuals from Cleveland, Ohio, who could see and read the pen’s directions.

Each participant first read instructions or listened to an audiotape about how to use the insulin pen. The instructions were essentially the same as those included on printed sheets in the insulin pen packaging, modified slightly to include tactile methods for using the pens. Then each participant measured out 10 doses of insulin and injected them into a rubber ball. The ball was weighed immediately before and after the insulin injections for dosage accuracy.

Generally there was little difference between the two groups in the accuracy of 600 dosages of insulin – although Williams reports the visually impaired group did slightly better.

For people with sight problems, measuring and administering insulin presents challenges, since most tools and techniques were designed assuming that people have good vision.

“People with visual impairment can manage their own insulin accurately when they have access to nonvisual tools and techniques and complete instructions in a format they can use,” Williams said.

“This study raises questions about the validity of the disclaimer that pharmaceutical companies put on the labels,” Williams said.

She added that if studies are designed correctly, people with disabilities can participate in research projects that impact their health.

The study was funded by the American Association of Diabetes Educators/Sigma Theta Tau International Research grant.

Williams’ research also was supported during her postdoctoral fellowship through a National Institutes of Health grant.

Source:
Susan Griffith
Case Western Reserve University

Eating Spinach Could Protect Your Eyes From The Leading Cause Of Blindness In Western Society, Say Experts At The University Of Manchester

With the aid of a new eye instrument, they have launched a study to see if the vegetable that endows Popeye with his super-human strength could also explain why the 77-year-old sailor has no need for spectacles!

Spinach and some other vegetables like sweetcorn, kale and broccoli are rich in a chemical called lutein, which, together with another carotenoid, zeaxanthin, form an oily, yellow substance at a central point of the retina known as the macula.

This yellow oil, called macular pigment, is thought to protect the macula from age-related macular degeneration or AMD, a disease that studies in the UK have shown to affect up to 12% of men and 29% of women over the age of 75.

“The macula is a small area of the retina responsible for seeing detail and colour in our central field of vision,” said Dr Ian Murray, who is leading the research in Manchester’s Faculty of Life Sciences.

“Our work has already found strong evidence to suggest that macular pigment provides some protection against AMD but we want to discover whether eating vegetables rich in these chemicals will have a direct impact on the disease.”

“Since macular pigment is wholly derived from our diet we would expect that eating foods containing high levels of these compounds increases macular pigment and so helps slow the degenerative process. This latest study on volunteers with early-stage AMD will test that idea.”

Scientists do not yet understand why some people are susceptible to age-related macular degeneration but warn the incidence is likely to rise as the population ages.

In collaboration with Tinsley Ophthalmic Instruments, Dr Murray’s lab has developed a lightweight instrument that can measure the levels of lutein and zeaxanthin and provide an indication as to whether low levels of macular pigment may be linked with premature visual impairment.

“If the instrument demonstrates that the patient has low levels of macular pigment then they can be advised to take a lutein or zeaxanthin supplement and encouraged to eat vegetables high in these carotenoids.”

“AMD is a devastating disease where sufferers slowly lose central vision making reading and most day-to-day activities virtually impossible. The main risk factors for the disease are age and heritance but it is also linked to controllable factors such as poor diet, smoking and obesity.”

“Having their macular pigment measured and learning about the health of their eyes might be the first step to a change in lifestyle for many people.”

MANCHESTER UNIVERSITY

Oxford Road
Manchester
M13 9PL
manchester.ac