Age-related macular degeneration can occur much earlier than originally thought

Age-related macular degeneration (AMD) is the most common cause of visual impairment and blindness in industrialized countries. But the question is whether it can be defined as a disease in people 50 or older. In a recent study to determine the incidence of age-related macular degeneration undertaken as part of the Gutenberg Health Study of the University Medical Center of Johannes Gutenberg University Mainz (JGU) results showed that even persons under the age of 50 may be affected by an early form of the eye disease. Just under 4 percent of the 35 to 44-year-old subjects in the population-based study were found to be suffering from AMD.

Macular Degeneration

National Eye Institute of the NIH

In order to identify the age- and gender-specific incidence of AMD, the research team assessed the status of the ocular fundus of 4,340 participants in the Gutenberg Health Study. Evaluated were vascular structure, the head of the optic nerve, and the macula of the eye, which is the point of sharpest vision. The results, not surprisingly, documented that the incidence of AMD increases with age. What was surprising, was the fact that even persons under the age of 50 can already be affected by early stage AMD. In the age group of 35- to 44-year-olds, 3.8 percent of the subjects in the Study were found to be suffering from the disease. The findings thus contradict the accepted assumption that age-related macular degeneration only occurs in the section of the population that is over 50 years old.

Age-related macular degeneration leads to loss of visual acuity. The cause is damage to the cells in the region of the central retina also known as the “yellow spot.” Information on the annual number of individuals who develop AMD is still insufficient, but the Mainz-based researchers hope to remedy this situation with their next project. As the Gutenberg cohort was subjected to a follow-up examination five years after inclusion in the study, the research group now has access to more relevant and reliable data. “The prospective design of the study, in combination with the availability of interdisciplinary research data, should make it possible for us to identify risk factors for the development of late forms of AMD in our cohort. We are looking forward with some excitement to the results,” explained the team.

With more on-going research projects like these we continue to learn more about the diseases that can affect our eyes and vision and in turn how we can treat and hopefully cure them.

Read the original article at https://www.sciencedaily.com/releases/2014/07/140721100125.htm

Human Eye Movements for Vision Are Remarkably Adaptable

Our eyes are constantly on the move, darting this way and that four to five times per second. Our eyes have the ability to change direction and focus at an incredible speed. 

A new study published in the Cell Press journal Current Biology on August 15, states that researchers have found that the precise manner of those eye movements can change within a matter of hours. This discovery might lead to a way to help those with macular degeneration better cope with vision loss.

“The system that controls how the eyes move is far more malleable than the literature has suggested,” says Bosco Tjan of the University of Southern California. “We showed that people with normal vision can quickly adjust to a temporary occlusion of their foveal vision by adapting a consistent point in their peripheral vision as their new point of gaze.”

The fovea is the small, center-most portion of the retina, which is responsible for our Eye Charthigh-resolution vision. In other words, it is the “pointer” we use to direct our eyes to different parts of a scene, building an image of our world. For those with age-related macular degeneration, increasing loss of foveal vision leads to visual impairment and blindness.

The researchers simulated a loss of foveal vision in six normally sighted young adults by blocking part of a visual scene with a gray disc that followed the individuals’ eye gaze. Once the disc was in place, the individuals were asked to complete demanding object-following and visual-search tasks.  The researchers found that within three hours of working on those tasks, all six participants showed a remarkably fast and spontaneous adjustment of eye movements. Once the visual adjustment had been made by the participants, the change in their “point of gaze” was retained for a period of weeks and was reengaged whenever their foveal vision was blocked.

Tjan and the other two researchers stated they were surprised by the rate of this adjustment. They note that patients with macular degeneration frequently do adapt their point of gaze, but in a process that takes months, not days or hours. They suggest that practice with a visible gray disc like the one used in the study might help speed that process of visual rehabilitation along. The discovery also reveals that the oculomotor (eye movement) system prefers control simplicity over optimality.  Tjan states “Gaze control by the oculomotor system, although highly automatic, is malleable in the same sense that motor control of the limbs is malleable.”

The result of this study is potentially very good news for people who experience loss of their foveal vision due to macular diseases. This study shows that it may be possible to create the right conditions for the oculomotor system to quickly adjust.

To read the original article, visit: https://www.sciencedaily.com/releases/2013/08/130815133447.htm

A Spoonful of Vegetable Oil Helps You See Better Longer?

Can vegetable oil help combat blindness? Turns out it can!

 The Research Center on Aging at the Health and Social Services Centre — University Institute of Geriatrics of Sherbrooke (CSSS-IUGS), England is the home of scientists who have been studying strategies for protecting retinal pigment epithelium (RPE) cells. There is a dysfunction of the RPE cells that is found in retinopathy and age-related macular degeneration, both of which are the leading causes of blindness in elderly people in developed countries.

Findings published in the Canadian Journal of Physiology and Pharmacology suggest that incubating retinal cells with vegetable oils induces biochemical and biophysical changes in the cell membrane, which may have a beneficial effect in preventing or slowing the development of retinopathy.

The research was centered around the fluidity of the membrane in the eye. The better the fluid in and around the membrane the smoother the eye operates.  When there is not enough membrane fluidity the rotation and diffusion of proteins are affected. However, an increase in the membrane fluidity enables the membrane to be more flexible and eases the transmission of light through the eye.

The researchers discovered that the fatty acids present in vegetable oil integrate in retina cells and increase the plasma membrane fluidity.

So what does all this mean?  The researchers concluded that a diet low in trans-unsaturated fats and rich in omega-3 fatty acids and olive oil may reduce the risk of retinopathy. Additionally, the research suggests that replacing the neutral oil found in eye drops with oil that possesses valuable biological properties for the eye could also contribute to the prevention of retina diseases.

This adds to the already established research that what you eat has a direct impact on your health and wellness.

To read the original article, visit: https://www.sciencedaily.com/releases/2013/08/130815113644.htm

Can Your Eyes Be a Window to Your Stroke Risk?

Your eyes may be a window to your soul, but could they also be a window to your stroke risk?

In a recent study detailed in the American Heart Association journal Hypertension, researchers state that retinal imaging may someday help assess if a person is more likely to develop a stroke.  This could be an invaluable diagnostic discovery – strokes Eyes and Strokesare the nation’s No. 4 killer and a leading cause of disability.

“The retina provides information on the status of blood vessels in the brain,” said Mohammad Kamran Ikram, M.D., Ph.D., lead author of the study and assistant professor in the Singapore Eye Research Institute, the Department of Ophthalmology and Memory Aging & Cognition Centre, at the National University of Singapore. “Retinal imaging is a non-invasive and cheap way of examining the blood vessels of the retina.”

Globally, high blood pressure is the single most important risk factor for stroke. However, until now there has not been a reliable way to predict which high blood pressure patients are more likely to develop a stroke.

THE STUDY:

Researchers tracked stroke occurrence for an average 13 years in 2,907 patients with high blood pressure who had not previously experienced a stroke. At the baseline, each patient had photographs taken of the retina, the light-sensitive layer of cells at the back of the eyeball. Damage to the retinal blood vessels attributed to hypertension — called hypertensive retinopathy — evident on the patient photographs was scored as one of four ways: none, mild, moderate, or severe.

THE FINDINGS:

During the follow-up, 161 participants experienced a stroke: 146 caused by a blood clot and 15 by bleeding in the brain.

After adjusting for several stroke risk factors such as age, sex, race, cholesterol levels, blood sugar, body mass index, smoking and blood pressure readings, researchers found the risk of stroke was 35 percent higher in those with mild hypertensive retinopathy and 137 percent higher in those with moderate or severe hypertensive retinopathy.  The researchers determined that even in patients whose blood pressure was successfully controlled by medication, the risk of a blood clot was 96 percent higher in those with mild hypertensive retinopathy and 198 percent higher in those with moderate or severe hypertensive retinopathy.

While this research opens the door for early risk detection in patients with hypertension, Ikram states “It is too early to recommend changes in clinical practice, other studies need to confirm our findings and examine whether retinal imaging can be useful in providing additional information about stroke risk in people with high blood pressure.”

More research is being done on the benefits of retinal imaging. But one thing is for sure:  retinal imaging would be an inexpensive and non-invasive way to assess risk.

To read the original article, visit: https://www.sciencedaily.com/releases/2013/08/130812170207.htm

Can a New Computer Game Improve the Sight of Visually Impaired Children?

A revolutionary new computer game being developed by an British team of neuroscientists and game designers could improve the sight of visually impaired children.

Academics from the University of Lincoln, UK, are working with WESC, one of the UK’s most respected specialist schools for visually impaired children, to create and evaluate a new ‘visual search rehabilitation game’.

Currently there are around 25,000 children in Britain (about two children per 1,000) with a visual impairment of such severity they require specialist education support. There are a myriad of causes of blindness in children, but cerebral visual impairment (damage to areas of the brain associated with vision, rather than damage to the eye itself) is one of the most the most common.

Researchers from Lincoln’s School of Psychology and School of Computer Science will work with staff and children from WESC – the specialist centre for visual impairment. The school and college, based in Exeter, have been providing education and care for young people with visual impairment since 1838 and is a designated High Performing Specialist School.

Jointly funded by a grant worth around £130,000 ($194,102.35 USD) for a Knowledge Transfer Partnership (KTP) the two groups will apply the very latest research in visual neuroscience to the rehabilitation of childhood cerebral visual impairment and special education.

There is existing research that shows that visual search training can lead to significant recovery of sight following damage to visual centers of the brain in adults. The issue has been that the existing training programs are just too boring to use with children.

The new game, designed specifically for children, will be a fun computer based tool which will benefit children with visual field loss – holes in their vision due to damage to the brain’s visual pathways.

The game will use the same principles derived from the existing programs in use with adults suffering from visual field loss.  The basic premise is that patients have to search for hard-to-find objects on a computer screen (a ‘visual search’ task), but the game will be modified to make the task more stimulating and fun for children and structured to maximize the efficiency of learning.

It is expected the new game will be suitable for rehabilitation of adults who have suffered sight loss due to stroke.

Read more: https://www.healthcanal.com/eyes-vision/37990-computer-game-could-improve-sight-of-visually-impaired-children.html

Does Low Birth Weight = Age-related Vision Loss?

A recent study suggests doctors may need to pay close attention to vision concerns in patients born with a low birth weight.

Medical researchers at the University of Alberta recently published findings of their study on rats with restricted growth in the womb, causing them to be born with low birth weights.  The study showed those rats were most susceptible to developing age-related vision loss, compared with rats born within the normal range of birth weight.

Additional work needs to be done to see whether this same link exists in people. If it does, doctors will need to incorporate better vision monitoring in adults who were born with a low birth weight.

Although most age-related eye diseases or vision loss can result from many different factors, this study may indicate that low birth weight could be an additional factor to consider.

The low birth weight rats in the study had overall poorer vision as they aged, they also had poorer night vision.  While it is normal for night vision to be slightly affected with age, the night vision loss was worse than normal in the test subjects as they aged.

Now all of this begs the question: How do they know what a rat can or cannot see and the degree of the difference??

Read more: https://www.healthcanal.com/eyes-vision/39986-low-birth-weight-may-be-risk-factor-for-age-related-vision-loss.html

Tetris – A Cure for Lazy Eye Disorder?

Researchers use the popular puzzle video game Tetris  to treat adult amblyopia or lazy-eye.

By distributing information between the two eyes equally, the video game trains the eyes to work together, which is the opposite of previous treatments for the disorder (e.g. patching).

This study provides direct evidence that forcing both eyes to cooperate, increases the level of plasticity in the brain and allows the amblyopic brain to relearn. The research is published in the prestigious journal Current Biology.

Amblyopia or lazy-eye is the most common cause of visual impairment in childhood, affecting up to 3 out of every 100 children. Caused by poor processing in the brain, the weaker eye is suppressed by the stronger eye. Previously treatments for the disorder have focused largely on covering the stronger eye in order to force the weaker eye to work harder, proved only partially successful in children and have been ineffective in adults.

For adults a study was created that set up conditions that would enable the two eyes to cooperate for the first time in a given task.

The adult human brain has a significant degree of plasticity which provides the basis for treating a range of conditions where vision has been lost as a result of a disrupted period of early visual development in childhood.  Researchers examined the potential of treating amblyopic adults using the video game Tetris, which involves connecting different shaped blocks as they fall to the ground.

By using head-mounted video goggles the game was displayed dichoptically, where one eye was allowed to see only the falling objects, and the other eye was allowed to see only the ground plane, resulting in the eyes being forced to work together.

The study used 18 adults with amblyopia. Nine participants played the game monocularly with the weaker eye, while the stronger eye was patched; the other nine played the same game dichoptically, where each eye was allowed to view a separate part of the game. After two weeks, the group playing the dichoptic game showed a dramatic improvement in the vision of the weaker eye as well as in 3-D depth perception.   When the monocular patching group, who had showed only a moderate improvement, was switched to the new dichoptic training, the vision of this group also improved dramatically.

The suitability of this treatment in children will be assessed later this year in a clinical trial across North America.

Learn more about this study and read the original article: https://www.healthcanal.com/eyes-vision/37920-lazy-eye-disorder-a-promising-therapeutic-approach.html

Eyeball licking can be dangerous…you’re kidding!

Eyeball-licking fetishism, also known as “oculolinctus” or “worming”, is gaining popularity as a way of expressing affection or inciting sexual arousal in Japan. With the increase of this activity, doctors are warning that there is a linkage to serious risk of virus conjunctivitis, other eye infections, and even blindness.

The oculolinctus craze in the country among young lovers has resulted in a significant increase in eye-infection cases. When the tongue makes contact with the eye, the eye is exposed to all kinds of infections and eye damage.

The trend of eyeball-licking was first documented when a Japanese school noticed that children were coming into class wearing eye patches. Apparently, one third of all the twelve-year-old children at the school had engaged in oculolinctus. This questionable trend was inspired by a Japanese emo band called “Born” in one of their music videos.

When interviewed by the Huffington Post on this phenomenon, ophthalmologist David Granet said “Nothing good can come of this. There are ridges on the tongue that can cause a corneal abrasion. And if a person hasn’t washed out their mouth, they might put acid from citrus products or spices into the eye.”

There is a very real risk of transmitting viruses. If the one who does the licking has herpes and/or a cold sore, there is a risk of human transmission via oculolinctus. If the licker suffers from halitosis (bad breath), they are more likely to have massive amounts of harmful bacteria in their mouth and on their tongue. Allowing such an individual to lick your eyeball (which has an absorbing membrane) puts you at risk of developing an infection.

Dr. Phillip Rizzuto, a spokesman for the American Academy of Ophthalmology said there is even a risk of eventual blindness. “The bacteria in the mouth are nothing like the bacteria in the eyeball, which is why we no longer recommend people lick contact lenses to moisten them.”

Animals use their tongues for personal hygiene (watch any pet cleaning itself). And in some cases, humans do the same (licking your thumb to remove a spot from your body). However, the tongue and mouth are designed to deal with a wide variety of pathogens that our eyeballs are not designed to deal with.  There are many practices in the animal world that do not translate well to the human world. I think I can safely say that we all prefer our traditional handshake to the traditional method of introduction in the dog world.

If you want to show someone affection, hold their hand, give them a kiss or a hug. But PLEASE don’t lick their eyeball!

To read the original article click here: https://www.medicalnewstoday.com/articles/262012.php

This Just In

New Layer In Human Eye Discovered

I just read an article dated June 16, 2013 about a new layer of the Human eye being discovered.  This is great news for those people who need to have corneal graft or transplant.

The new layer, located in the front layer of the eye, is being called the “Dua Layer”, so named after the researcher (Professor Harminder Dua) who led the study in which the discovery was made. Dua explained the significance of the discovery in this way:

Having identified this new and distinct layer deep in the tissue of the cornea, we can now exploit its presence to make operations much safer and simpler for patients.”

He went on to add:

“From a clinical perspective, there are many diseases that affect the back of the cornea, which clinicians across the world are already beginning to relate to the presence, absence, or tear in this layer.”

With over 65,000 penetrating corneal graft procedures being carried out worldwide each year, surgeons will benefit considerably by understanding more about the new Dua’s layer, which will improve outcomes for patients undergoing corneal grafts and transplants.

This discovery will alter the way these surgeries are preformed and therefore chances of tearing during surgery will be significantly reduced.

On a side note, this discovery means that ophthalmology and anatomy textbooks will literally have to be re-written. Not a bad price to pay for the advancements this discovery will yield.

Click here to read the original article: New Layer in the Human Eye Discovered

Here Comes the Sun

Summer is upon us! We protect our skin with sunscreen, but do we need to protect our eyes too? Most people are aware of the dangerous effects ultraviolet (UV) rays have on our skin, but most don’t realize the danger to our eyes. UV radiation can burn the front surface of the eye, similar to a sunburn on the skin. It can also damage the eye’s surface tissues, the cornea and lens.

UV radiation is the invisible rays from the sun. There are three types of UV radiation: UVA, UVB and UVC. UVC rays are absorbed by the ozone layer, and therefore pose no threat to us. However, exposure to UVA and UVB rays can have adverse effects on your eyes and vision. Short- and long-term exposure to these dangerous rays can cause significant damage. The sun is not the only source of UV radiation; artificial sources like welding machines, tanning beds and lasers also emit UV radiation.

Unprotected exposure to excessive amounts of UV radiation over a short period of time, can result in photokeratitis. Photokeratitis is an inflammation of the cornea caused by a brief exposure to UV radiation, usually when combined with cold wind and snow. This “sunburn of the eye”, it may be painful and exhibit symptoms including red eyes, a foreign body sensation or gritty feeling in the eyes, extreme sensitivity to light and excessive tearing. The good news is this is usually temporary condition and rarely causes permanent damage to the eyes.

Scientific studies and research growing out of the U.S. space program have shown that exposure to small amounts of UV radiation over a prolonged period of time (years) may increase the chance of developing a cataract and may cause damage to the retina. This damage is usually not reversible. Cumulative damage of repeated exposure may contribute to chronic eye disease, and increase the risk of developing skin cancer around the eyelids. Long-term exposure to UV light is also a risk factor in the development of pterygium (a growth that invades the corner of the eyes) and pinguecula (a yellowish, slightly raised lesion that forms on the surface tissue of the white part of your eye.)

Although we know that exposure (both short and long-term) may damage the eyes,Ii is not yet known how much exposure will cause how much damage. A good rule of thumb is to wear quality sunglasses that offer good protection and a wide-brimmed hat when doing anything in the sun.

When choosing sunglasses, use these guidelines:

  • block out 99 to 100 percent of both UV-A and UV-B radiation
  • screen out 75 to 90 percent of visible light
  • be perfectly matched in color and free of distortion and imperfection

When it comes to the color of the sunglass lens its really personal preference… Gray and Green are less color distortion, but brown is fine too, some people prefer it for glare. I’ve worn all kinds, brown gray, green, polarized or non-polarized and as long as the frame is a comfortable fit and the lenses have all the qualifications for protection that is fine.

Wrap-around frames can provide additional protection from harmful UV radiation by keeping UV rays from reaching the eyes. Don’t forget to the UV eye protection for children and teenagers. They typically spend more time in the sun than adults. Finally, even if you are wearing contact lenses that have UV protection, you still need to wear sunglasses. UV rays can affect the eye tissue that is not covered by the contacts.

So when you grab the sunscreen, grab a good pair of sunglasses too!