Risk Of Blindness Halved Over Last Decade

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Age-related macular degeneration (AMD) is the most frequent cause of blindness in the Western World. A report from the University of Copenhagen and Glostrup Hospital in Denmark shows the number of new cases of blindness and severe visual loss in Denmark has been halved during the last ten years.

The study just published in American Journal of Ophthalmology examined the records of 11,848 new cases of legal blindness. The rate of blindness from AMD fell from 522 cases per million inhabitants aged 50 years or older in 2000, to 257 cases per million in 2010, a reduction by over 50 per cent.

The bulk of the decrease occurred after 2006, following the introduction of new effective treatment for wet AMD, which is characterised by leaking blood vessels having formed under the fovea. The treatment consists of repeated injections into the eye of a medication that inhibits the signalling molecule vascular endothelial growth factor (VEGF).

Similar findings in Israel

The observations from Denmark were published together with a corroborating report from Israel that found comparable changes in the incidence of legal blindness in that country. Read the report “Time Trends in the Incidence and Causes of Blindness in Israel”.

Current treatment of wet AMD, also called neovascular AMD, consists of repeated injections into the vitreous, an inner compartment of the eye, of a medication designed to inhibit the action of VEGF. VEGF is a distress signal released from ailing cells of the aging retina. VEGF can cause formation of brittle blood vessels that leak blood and cause scar formation under the fovea. The fovea is central area of the retina where reading vision is located. Wet AMD is a very frequent cause of loss of reading vision.

Results show impact on public health

One of the authors behind the Danish study, Michael Larsen, Professor of Clinical Ophthalmology at the University of Copenhagen, is excited about the results.

“The massive implementation of modern wet AMD therapy has been a challenge. It is therefore very important that we can now show an impact on public health and it is wonderful to see a reduction in severe visual loss. The study did not examine moderate visual loss, but there are undoubtedly also a lot of people who avoided loosing their drivers licence and their reading vision,” says Michael Larsen.

A turning point in eye care

The data for the study is provided by Danish Association of the Blind, which membership enrolment during the period of 2000-2010 was charted and categorised by diagnoses.

“The reduction in new cases of blindness is a turning point for eyecare in Denmark. We look forward to seeing further progress in eye research, especially in the hereditary eye diseases that cause blindness in children and young adults,” says Thorkild Olesen, Chairman of the Danish Association of the Blind. 

Stem Cell Treatment For Blindness Shows Promise In Trials

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The first published results of trials using cells derived from human embryonic stem cells appear to show they have passed an initial safety hurdle. In The Lancet this week, researchers report that two nearly blind patients, one with Stargardt’s macular dystrophy and the other with dry age-related macular degeneration (the leading cause of blindness in developed countries), showed measurable improvements in vision that lasted for more than four months after receiving injections of retinal pigment epithelium cells derived from human embryonic stem cells.

The retinal pigment epithelium (RPE) cells were developed by the US stem cell company Advanced Cell Technology (ACT), and the trials were conducted at the Jules Stein Eye Institute at the University of California, Los Angeles. The report appeared online in The Lancet on Monday 23 January.

Both trials are designed as prospective “open label” trials to test the safety and tolerability of sub-retinal transplantation of RPE cells made from stem cells derived from human embryos.

As well as these two trials taking place in the US, another trial for SMD is just starting in the UK, and the first patient was treated at Moorfields Eye Hospital in London last Friday.

The researchers write in The Lancet:

“It has been 13 years since the discovery of human embryonic stem cells (hESCs). Our report provides the first description of hESC-derived cells transplanted into human patients.”

The apparent success of the trials, which at best showed that vision improved slightly, and at worst, that it did not deteriorate and there were no adverse safety issues, could signify a major boost to the field of stem cell research which has found itself in the doldrums lately.

And in this particular case, they offer hope to millions of people with AMD, whose numbers are increasing every year. In the US alone, the number of people with AMD is estimated to reach 2.95 million by 2020, according to the Centers for Disease Control and Prevention (CDC).

Macular degeneration, often called age-related macular degeneration (AMD), is an eye disorder associated with aging where people’s vision becomes less sharp and they gradually lose central vision, which is essential every day tasks such as reading and driving.

AMD affects the macula, the middle part the retina that allows the eye to see fine details. There are two forms of AMD, wet and dry. And although dry is by far the most common form of AMD, unfortunately drugs are only available for wet AMD.

Dr Robert Lanza is the chief scientific officer of ACT and the senior author of the paper. He told the press the “safety and engraftment data to date look very encouraging”, and that despite the progressive nature of Stargardt’s macular dystrophy (SMD) and AMD:

Bionic Contact Lens Could Stream Emails, News And Medical Information

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In a move that could revolutionize the way we think of hands-free communication, scientists have invented a bionic contact lens that could display real-time news, emails and text messages only millimeters from your retina.

“People may find all sorts of applications for it that we have not thought about,” Babak Parviz, UW assistant professor of electrical engineering said in a research announcement poste on the department’s website. “Our goal is to demonstrate the basic technology and make sure it works and that it’s safe.”

In the joint study between the University of Washington and Aalto University in Finland, researchers safely tested the bionic display contact lenses on rabbits for up to 20 minutes with no adverse effects.

According to TIME magazine, the anesthetized animals could tolerate the wearable contact lensesfor short periods of time while showing no abrasions or thermal burning.

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Photo courtesy of the University of Washington

To create the bionic contacts, scientists installed a single LED light and wireless antenna into the contact lens, which is made from delicately thin materials, according to the Daily Mail.

But scientists still have plenty of hurdles to clear before they can can bring the Terminator-like lenses to the market. The device’s small size means researchers only have enough space for one LED, making the display of complex information much more difficult.

Another challenge is powering the microscopic circuits inside the lens. Currently, the lens can only function if it stays within centimeters of its wireless battery.

“Our next goal is to incorporate some predetermined text in the contact lens,” Praviz said in an interview with the BBC.

The study comes at a time when scientists are similarly looking to develop an alternative pain-free device to monitor glucose levels of diabetics by utilizing a sensor to read eye whites or tears.

Learning to See Consciously: Scientists Show How Flexibly the Brain Processes Images

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Our brains process many more stimuli than we become aware of. Often images enter our brain without being noticed: visual information is being processed, but does not reach consciousness, that is, we do not have an impression of it. Then, what is the difference between conscious and unconscious perception, and can both forms of perception be changed through practice? These questions are important not only for basic research, but also for the treatment of patients with perceptual deficits due to brain lesions e.g. following a stroke. Scientists at the MPI for Brain Research in Frankfurt/Main could now show that seeing can be trained. Today, we know that the processing of stimuli in the cortex remains extremely plastic, or malleable, even in adults
Experiments have shown that the neuronal processes that underlie conscious perception are very flexible,” Schwiedrzik concludes. The findings provide important insights for medical applications, in particular for the rehabilitation of people suffering from perceptual deficits caused by brain lesions.

Lumigan, Latisse Drug Class and Mechanism

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GENERIC NAME: bimatoprost

BRAND NAME: Latisse, Lumigan

DRUG CLASS AND MECHANISM: Bimatoprost is a synthetic (man-made) drug that resembles and mimics the effects of natural chemicals (prostaglandins) produced by the body. It is used for reducing intraocular pressure (IOP) and increasing the growth of eyelashes. The exact mechanism of action is unknown. Bimatoprost may reduce IOP by increasing the outflow of aqueous humor from the eye of individuals with narrow angle glaucoma. Excessive aqueous humor may cause optic nerve damage and visual loss. It may increase eyelash growth by increasing the duration of the growing phase of the eyelash. The FDA approved Lumigan in March 2001 and Latisse in December 2008.

Noninvasive Current Stimulation Improves Sight in Patients With Optic Nerve Damage, Study Suggests

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It has long been thought that blindness after brain lesions is irreversible and that damage to the optic nerves leads to permanent impairments in everyday activities such as reading, driving, and spatial orientation. A new study published in Elsevier’sBrain Stimulation suggests that treating such patients with low levels of non-invasive, repetitive, transorbital alternating current stimulation (rtACS) for 10 days (30-40 min per day) significantly reduces visual impairment and markedly improves vision-related quality of life.

FDA Approves Eylea For Wet Macular Degeneration

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The U.S. Food and Drug Administration approved Eylea (aflibercept) to treat patients with wet (neovascular) age-related macular degeneration (AMD), a leading cause of vision loss and blindness in Americans ages 60 and older.
Other FDA-approved treatment options for wet AMD include: Visudyne (verteporfin for injection) approved in 2000, Macugen (pegaptanib sodium injection) approved in 2004, and Lucentis (ranibizumab injection) approved in 2006.
Studies showed that Eylea was as effective as Lucentis in maintaining or improving visual acuity.

How Space Flight Impacts Astronauts’ Eyes And Vision

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The authors reported eye exam findings in seven astronauts as well as an analysis of post-flight questionnaires regarding in-flight vision changes in approximately 300 additional astronauts. The seven astronauts with ocular anomalies had returned from long-duration space missions to the International Space Station (ISS) and all seven subjects had undergone complete eye examinations, including dilated exams and photographs of the back of the eye. Several had MRI scans, spinal taps, and computerized analysis of their optic nerve. After 6 months of space flight, all 7 astronauts had eye findings, including swollen optic nerves, distortion of the shape of the eyeball, and retinal changes. Most became more farsighted, and had blurred vision, especially at near. The spinal taps showed either top normal or slightly elevated pressures in the spinal fluid surrounding the brain and optic nerves.
The 300 post-flight questionnaires documented that approximately 29% and 60% of astronauts on short and long-duration missions, respectively, experienced a worsening of distance or near visual acuity. Some of these vision changes remain unresolved years after flight. The authors theorized that changes may have resulted from fluid shifts brought about by prolonged exposure to low gravity. The findings might represent parts of a spectrum of ocular and brain responses to extended exposure to low gravity. Future research is ongoing for astronauts entering new missions. 

More Time Outdoors May Reduce Kids’ Risk for Nearsightedness, Research Suggests

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ScienceDaily — A new analysis of recent eye health studies shows that more time spent outdoors is related to reduced rates of nearsightedness, also known as myopia, in children and adolescents. Myopia is much more common today in the United States and many other countries than it was in the 1970s. In parts of Asia, more than 80 percent of the population is nearsighted. The analysis suggests that more exposure to natural light and/or time spent looking at distant objects may be key factors.

AMD-Like Lesions Delayed in Mice Fed Lower Glycemic Index Diet

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ScienceDaily (Nov. 14, 2011) — Feeding older mice a lower glycemic index (GI) diet consisting of slowly-digested carbohydrates delays the onset of age-related, sight-threatening retinal lesions, according to a new study from the Laboratory for Nutrition and Vision Research at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University.

What are Low Glycemic Foods?
This means foods that have carbs that break down more slowly so that your blood sugar does not rise so rapidly. Examples would be grainy breads, fish, cheese, nuts, and brown rice.