February 2018


LEARNING TO SEE

The visual system is the most complex sensory system in the human body, but is the least mature at birth, constantly changing and developing as the baby grows. Although babies are born with the structures needed for sight, they need to learn to use them over a period of time. As well as learning to focus the eyes, move them accurately, and use them together, babies need to learn how to use the information the eyes send to the brain in order to make sense of the world around them. Babies develop according to their own individual schedules but being aware of the milestones of visual development can guide parents in how to stimulate their babies and to alert them to possible problems.
 

Birth to three months

Just after birth, the baby sees in black and white, but gradually begins to look intently at a target in bold contrasting colours. By two to three months, he will begin to show a preference for bright colours. At birth, his field of vision is only about 20cm, and he will focus for a few seconds on a face within his field of vision. Over the next few weeks as his peripheral vision develops and his attention span increases, he is able to make eye contact and hold his gaze on a familiar face for a little longer. He can recognise a smile, and by 6 to 8 weeks will respond with a smile of his own. He may start to look at things to either side as they move back and forth, and will do so by moving his head rather than his eyes. The eyes begin to move independently from the head at about three months of age. The eyes are not well-coordinated yet, and until about two months of age, it is normal for the eyes to appear to wander or be crossed.
 
As vision-hearing coordination begins to emerge, the baby will respond to a sound by looking at its source, for example a rattle. By three months, the baby is able to track moving objects with his eyes, reaching for them as eye-hand coordination develops. He discovers his hands and feet, and spends time intently watching their movements. He holds eye contact for long periods of time, and is fascinated by facial expressions as he is spoken, read or sung to.
 
Although pastel colours are often used to decorate nurseries, bright primary colours are naturally stimulating for visual development. This is why babies' toys are bold-patterned and vividly coloured. A mobile over the pram or crib, or a baby gym will facilitate tracking and help with eye-hand coordination as he reaches for objects hanging at different levels. Throughout the development of the baby's vision, especially in the first 3-4 months, the best visual stimulation is a caregiver's face. To encourage the development of focus and visual attention, maintain eye contact while feeding the baby, smiling and talking to him.
 

Three to six months

By six months the baby will be moving his eyes with more speed and accuracy, seeing at further distances and focusing well. He will keenly watch the activity around him, and if something changes position in his field of vision, will move his eyes to look at it. His visual sphere of attention begins to widen. Now when he sits in front of the window, he sees through the glass pane rather than focusing on the glass. As eye-hand coordination and depth perception improve, the baby will begin to understand the three-dimensional world around him. He is beginning to grasp the concept of object permanence, and will know that even if a toy is hidden it still exists. He immediately recognises familiar faces, and enjoys looking at his own reflection in a mirror.
 
Toys, pictures and the world around him are of tremendous interest to the baby, so ensure that there are objects within reach to stimulate his vision and develop eye-hand coordination. Include patterns, shapes and noise-making toys that will hold his visual attention as well as enhance listening. A baby is never too young to be introduced to books – show him books with bright simple pictures. Games like peek-a-boo and hidden objects are an enjoyable way of developing the knowledge of object permanence.
 

Six to twelve months

During this period development takes place rapidly in all areas, and the baby will be coordinating vision with body movements, as he learns to sit, crawl, pull himself up to stand and explore his world. Vision becomes more refined. He notices small objects and is able to manipulate them more easily, grasping them between his thumb and forefinger rather than with his whole hand. He can judge distances reasonably well, enjoys throwing objects, and throws them with precision. By the end of his first year the baby has good colour vision, differentiates between near and far, and can recognise an object at a distance. His eye colour will be established.
 
Encourage the baby to explore his environment by placing toys just out of reach, motivating him to move to fetch them. Provide toys that can be pushed or pulled, as well as toys that can be manipulated, taken apart and fitted together again, like building blocks and nesting cups. Develop his interest in books by allowing him to turn the pages of cardboard books and choosing pictures that interest him.
 

Twelve to twenty-four months

By the time he is a toddler, a child's eye-hand coordination and depth perception should be well developed. He is learning about his world by exploring and experimenting, looking and listening. Encourage him to express what he is experiencing. The child is able to recognise familiar objects and can find pictures that interest him in books. He is refining his ability to discriminate shapes and colours. He enjoys scribbling with a crayon. Provide opportunities for him to enhance his visual memory and discrimination skills. Roll a ball back and forth to help the child strengthen his visual tracking ability.
 

Warning signs

Healthy eyes play a critical role in how infants and children learn to see. Most babies begin life with healthy eyes and start to develop the visual abilities they need throughout life without difficulty. Occasionally, vision problems can occur, and it is important to detect and treat these early to ensure that babies have the opportunity to develop the visual abilities they need to grow and learn. Parents need to be aware of the signs that may indicate eye or vision problems, and may require medical intervention.
 
Excessive tearing - this may indicate blocked tear ducts.
 
Encrusted eye lids - this could be a sign of an eye infection.
 
Persistent redness in the eye or eyelids – this could indicate infection or allergy.
 
Constant eye turning - this may signal a problem with eye muscle control.
 
Crossing of the eye(s) - some crossing is normal in babies in their first few months, but if the eyes are constantly crossed in or out for long periods of time, this could be a problem.
 
Persistent eye pain, itching, or irritation.
 
Drooping eyelids.


LIGHT HURTS

Are we "darkness deprived"?

With the widespread and ever-increasing use of electronic devices, there is a growing cause for concern regarding the impact of blue light on our eyes. Screen use is subjecting our eyes to temporary eye fatigue and could lead to permanent eye damage, particularly amongst children, whose eyes are not yet fully developed. Many questions still exist on the subject of blue light, and a great deal of research is being conducted. One researcher in this field is quoted as saying: "As opposed to the many other kinds of harmful environmental pollutants out there, we are rapidly figuring out exactly what to do about this one, and it is really not that hard".
 

WHAT IS BLUE LIGHT?

Sunlight is made up of red, orange, yellow, green, blue, indigo and violet light. Each of these has a different wavelength and energy. When combined, this spectrum of coloured light rays creates the white light that is visible to the human eye. Rays on the red end have longer wavelengths and less energy. On the other end, blue rays have shorter wavelengths and more energy. While blue light is naturally present in sunlight, a major source of blue light exposure is found in emissions from artificial lighting and the electronic devices we use every day. Blue light exposure received from screens is small compared to the amount of exposure from the sun but concerns over the long-term effect on the eyes stem from the close proximity of the screens and the length of time spent looking at them.
 
Not all blue light is harmful. In fact, the two bands of blue light, blue-violet and blue-turquoise, exhibit vastly different effects on the eyes. Besides helping with visual acuity, contrast acuity, and colour vision, blue-turquoise light plays a vital role in maintaining general health. It is essential for synchronisation of our circadian rhythms, the body's natural wake and sleep cycles, which in turn help to maintain and regulate memory, mood, cognitive function and hormonal balance. Blue-violet light, on the other hand, is harmful to the retina and over time causes retinal cell death.
 

HOW BLUE LIGHT AFFECTS THE EYES

Almost all visible blue light passes through the cornea and the lens of the eye, without being filtered out, and reaches the retina at the back of the eye. At the very least, this can lead to temporary eye fatigue and strain, the symptoms of which include blurry vision, red, tired eyes, dry eyes and headaches. Studies indicate that it may lead to long-term damage of the retinal cells, resulting in problems such as cataracts and age-related macular degeneration, a major cause of irreversible vision loss.
 

PROTECTING THE EYES FROM BLUE LIGHT

To protect against eye strain, disrupted sleep and eye damage, it is important to take precautions. While we all need to take responsibility for our own eye health, your optometrist will advise you on the most appropriate protection against blue light based on your lifestyle, work environment and personal comfort. There are a number of simple common-sense strategies that can be implemented.
 
Give your eyes a break! Although not always an easy option, try to decrease the amount of time spent looking at digital screens or take frequent breaks. Carry out the 20-20-20 rule – every 20 minutes for 20 seconds look away from the screen at something 20 feet away. This helps to reduce eye fatigue and strain by refocusing the eyes.
 
Remember to blink. When we concentrate we reduce our blink rate, causing tears to evaporate from the surface of the eyes and resulting in blurry vision, redness and eye irritation.
 
Dim the brightness of screens, use screen filters or download a light-reducing app to minimise blue light and glare from digital devices.
 
Discuss with your optometrist wearing a pair of computer glasses to block blue light and ease digital eye strain while working on computers. Anti-reflective lenses and sunglasses that reduce glare and block blue light and UV rays from the sun have been reported by some people to help the eyes feel more comfortable and less fatigued. Many of the blue-blocking lenses distort colours, and research is constantly being conducted to produce lenses that reduce levels of exposure to the harmful blue-violet portion of the spectrum while permitting the rest of the visible spectrum to enter the eye at normal levels. This would allow the eye's necessary functions to be maintained while exposure to hazardous wavelengths would be reduced.
 
Easier said than done but the best way to prevent digital devices from interfering with sleep cycles is to turn them off an hour before bedtime! It has been suggested that in addition to minimising blue light at night, we should try to maximise the amount of natural light we get during the day.
 
Encourage children to play outdoors, exposing them to the natural light of the sun and cutting down their time on digital screens.
 
The use of digital devices is here to stay, and in fact is on the rise. Adequately protecting the eyes during adolescence and early adulthood could go a long way in reducing the risk of irreversible eye damage in the older years.


EYE OPENERS

Humans are a highly visual species, and our eyes are one of the most fascinating and complex organs of the body. Most of the information captured in our brain is through our eyes, which are also a means of expressing our emotions and feelings, and detecting the emotions in others. Here are some interesting facts related to the eyes of humans and animals.
 
The eye is the fastest muscle in the body, which is why when something happens quickly, we say 'in the blink of an eye!'
 
We see with the brain, not the eyes. The eyes function like a camera, capturing light and sending the information to be interpreted by the brain.
 
We see things upside down - it is the brain which turns the image the right way up.
 
Eyes are the second most complex organ after the brain.
 
About half of our brain is involved in the seeing process.
 
We have two eyeballs in order to give us depth perception – comparing two images allows us to determine how far away an object is from us.
 
People generally read 25% slower on screen than on paper.
 
It is a myth that it is impossible to sneeze with the eyes open. While it may be difficult, it is possible to sneeze with open eyes. Sneezing elicits a blinking response that is thought to be a protective mechanism to prevent irritants from entering and aggravating the eyes.
 
The human eye can function at 100% at any given moment.
 
The eyes contain 7 million cones which help us see colour and detail, as well as 100 million cells called rods which help us to see better in the dark.
 
Our eyes close automatically to protect us from perceived dangers.
 
The eyes start to develop just two weeks after conception.
 
The older we get, the less tears we produce.
 
Eyes are able to process 36,000 pieces of information in a single hour.
 
Colour blindness is more common in males than females.
 
Reading in dim lighting does not damage the eyes but it may tire them out.
 
Only one sixth of the human eyeball is exposed.
 
Contrary to urban myth, contact lenses cannot become 'lost' behind the eye due to the structure of the eyeball.
 
The eyeball weighs around 28 grams.
 
Although the function of tears is to keep eyes clean and lubricated, scientists don't understand why we cry when we are upset.
 
80% of our memories are determined by what we see.
 
While a fingerprint has 40 unique characteristics, an iris has 256. For this reason iris scans are increasingly being used for security purposes.
 
In an average life, your eyes will see 24 million different images.
 
Newborns don't produce tears. They make crying sounds, but the tears don't start flowing until they are about 4 weeks old.
 
All babies no matter what nationality or race, have blue eyes in the womb.
 
Some people are born with two differently colored eyes, a condition called heterochromia.
 
Each of the eyes has a small blind spot in the back of the retina where the optic nerve attaches. You don't notice the hole in your vision because the blind spots are aligned symmetrically so that most of the time one eye's field of vision will compensate for the loss of vision in the other.
 
The average person blinks 12 times per minute – about 10,000 blinks in an average day.
 
Women blink nearly twice as much as men.
 
The average blink lasts for about 1/10th of a second.
 
We blink more when we talk than when we read or work on a computer.
 
The word "eyeball" was coined by William Shakespeare in 'A Midsummer Night's Dream'.
 
At any given point, the eyes are moving 70 to 100 times per second.
 
To protect our eyes they are positioned in a hollowed eye socket, while eyebrows prevent sweat dripping into the eyes and eyelashes keep dirt out of the eyes.
 
The cornea is the only tissue in the body that does not have a blood supply. It gets oxygen and nutrients from the tear fluid in its outer part and from the aqueous humour (the gel-like substance) in the inner eye.
 
"Red eye" occurs in photos because light from the flash bounces off the back of the eye. The choroid is located behind the retina and is rich in blood vessels, which make it appear red on film.
 
We spend about 10% of our waking time with our eyes closed.
 
Ommatophobia is the fear of eyes.
 
Humans can see more shades of green than any other colour.
 
The lifespan of the average eyelash is 5 months, the rest of the hair will last 2-4 years.
 
The external muscles of the eye are large in relation to the small size and weight of the eyeball, and are the strongest muscles in the body for the job they do. The muscles of the eye constantly move to readjust the position of the eye even when the head is in motion. They continue to work during sleep as we constantly move our eyes during rapid eye movement (REM) sleep.
 
The amount of light entering the eye is constantly controlled by the pupil, the central opening of the eye, which changes size depending on the amount of light entering the eye. The iris, the coloured area around the pupil, controls the size of the pupil.
 
A camel's eyelashes can measure up to 10cm long, to protect its eyes from blowing sand and debris in the desert. As well as that camels have three eyelids. The eyes of a chameleon are independent from each other, allowing it to look in two different directions at once.
 
Bees have 5 eyes.
 
A dragonfly has 30,000 lenses in its eyes, assisting it with motion detection and making it very difficult for predators to kill.
 
Owls cannot move their eyeballs but are able to turn their heads almost all the way round to see in different directions.
 
Goats have rectangular pupils to give them a wide field of vision.
 
Most hamsters only blink one eye at a time.
 
An ostrich's eye is bigger than its brain.
 
Dolphins can sleep with one eye open.
 
Birds, cats and dogs have three eyelids.
 
Humans and dogs are the only species known to seek visual cues from another individual's eyes, and dogs only do this when interacting with humans.


EAT A RAINBOW

Don't want to wear glasses? Eat your carrots!

Carrots have long been touted for their efficacy in improving eyesight, and generations of kids have been admonished not to leave them on their plates lest they end up needing glasses. Where did this belief begin? The purported link between carrots and markedly acute vision is a matter of lore, not of science. The story goes back to World War II, and was deliberately manufactured by Britain's Air Ministry.
 
During World War II, the Allies had perfected Airborne Interception Radar which helped with both night raids into enemy territory and the detection of bombers attacking at night. Not wanting the enemy to find out about this new technology, the rumour was circulated that eating carrots had dramatically improved the night vision of British fighter pilots. The British public were encouraged to grow and eat more carrots, and the disinformation was so persuasive that people believed that eating carrots helped them to find their way during blackouts. One report suggests that some people ate so many carrots that their skin began to look orange. Another woman comments that her mother made her eat so many carrots that this is probably the reason she doesn't eat them now!
 

Beta-carotene

While not the total picture, there is some truth to the claims that eating carrots contributes to eye health. Research indicates that beta-carotene, which is found in carrots, may help reduce the risk of cataracts and macular degeneration as well as helping those who suffer from night blindness. The body uses beta-carotene to make vitamin A, an essential nutrient for vision, but there is conflicting evidence as to how much beta-carotene is needed for efficient conversion to vitamin A. There is general agreement that vitamin A is not the only contributor to good eyesight, and that including a range of nutrient-rich foods in the diet can help preserve vision.
 

Vitamin A

The A vitamins, which include beta-carotene, help the retina, cornea, and other eye tissues to function effectively. As well as carrots, foods that supply vitamin A to the body include liver, fish, eggs, spinach, sweet potatoes and dairy products.
 

Lutein & Zeaxanthin

Lutein and zeaxanthin are important nutrients found in green leafy vegetables, such as kale and spinach, brightly coloured fruits and vegetables, such as kiwi, red peppers and pumpkin, as well as other foods, such as eggs. These antioxidants protect the eyes against the damaging effects of sunlight, cigarette smoke and air pollution, and help to filter out harmful blue light and reduce hazardous free radicals in the macula. They may lower the risk of cataracts. Zeaxanthin appears to be the most active antioxidant in the macula specifically, and may delay the onset or reduce the severity of age-related macular degeneration.
 

Vitamin C

Vitamin C (ascorbic acid) is an antioxidant, which contributes to the health of the blood vessels in the eyes. It is thought to lower the risk of developing cataracts and slow the progression of macular degeneration, particularly when taken in combination with other essential nutrients. Foods rich in vitamin C include citrus fruits, berries, red and green peppers, cauliflower, broccoli, papaya, and Brussels sprouts.
 

Vitamin E

Vitamin E is a powerful antioxidant which seems to protect cells in the eyes from the damage caused by free radicals which break down healthy tissue. It is found in nuts, fortified cereals, sweet potatoes, vegetable oils, sunflower seeds and peanut butter.
 

Essential Fatty Acids

Fats are a necessary part of the human diet. They maintain the integrity of the nervous system, fuel cells and boost the immune system. There needs to be a balance between omega-3 and omega-6 fatty acids in the diet, with an increased intake of omega-3 and decreased intake of omega-6. Research shows that omega-3 fatty acids play an important role in visual development, retinal function and the prevention of dry eyes. They decrease inflammation and promote general eye health.
 
Fish, particularly salmon, tuna and mackerel, are an excellent source of omega-3 fatty acids. Other sources include green vegetables, vegetable oils and walnuts.
 

Zinc

High doses of zinc in the eye, in combination with other antioxidants have been found to significantly reduce the risk of developing advanced macular degeneration. While it does not repair the damage caused by macular degeneration, it does help to slow the progression of the condition. It is found in high concentrations in the retina and the vascular layer underneath the retina. Foods rich in zinc include egg yolk, red meat, whole grains, seafood, nuts and beans.
 

Eat a Rainbow

With some nutrients, more is not necessarily better. A balanced diet with a variety of protein, fats, vegetables, fruit and dairy products will help towards promoting eye health and preserving vision. It has the added protective benefits against physical conditions that can lead to vision problems, such as diabetes, stroke, and vascular diseases that affect blood vessels throughout the body including the delicate vessels of the eyes. Try to eat a rainbow during your day, incorporating many types of foods in many different colours. Limit consumption of unhealthy foods that are processed, contain saturated fats, or are high in sugar.


RIDE FOR SIGHT 2018

The Dis-Chem Ride for Sight takes place in Ekurhuleni in Gauteng in February annually. This popular race is among the top five road cycling events in South Africa, and is a seeding event for both the Cape Town Cycle Tour and the Momentum 94.7 Challenge. It has been staged since 1987 and has contributed more than R4 Million to 'A Cure in Sight for Blindness' research projects. The ride attracts more than 5000 keen and enthusiastic cyclists every year and is now an official City of Ekurhuleni event.
 
The 30th edition of the Ride for Sight will be held in Boksburg, Ekurhuleni on Sunday 18th February 2018. We have a special 30th Anniversary logo and there are exciting prizes and special offers for the participants. Once again a cash prize is being offered to the first blind Tandem pair on the 63 km event.
 
This is a fast, moderately undulating route. The race begins with a quick downhill ride. You will find the going to the halfway mark a combination of both fast and flat sections. Keep something in reserve for the second half, which is demanding and hilly. There is a slight uphill and steady climb to the finish.
 
ENJOY THE RIDE!!
 

RETINA SOUTH AFRICA – "A CURE IN SIGHT FOR BLINDNESS"

Retina South Africa was established in 1980 as the South African Retinitis Pigmentosa Society. It is a patient-driven action group that has branches in all the major centres in South Africa.
 
Our major focus is:
    Support of the Retinal Degeneration Research project at the University of Cape Town to find the genetic mutations in South African families
     
    Facilitation of genetic testing to identify those patients who will benefit from clinical trials and imminent therapy
     
    Public Awareness of retinal degeneration
     
    Patient support including education, referral and intervention
     
    Collaboration with local and international agencies and researchers
     
    Fund raising to support this work
Membership is open to all patients, family members and persons who wish to support our quest to find treatments for Retinal blinding conditions. All proceeds go directly to research to find treatments for genetic retinal conditions. Ride for Sight is one of our main annual fund-raising projects.


FEBU-REALLY?!

So we come out of the year's longest month. And yes, you know it's the year's longest month if you've ever tried to stretch a paycheck from December 20th until January 25th. I mean, they don't call it Januworry for nothing.
 
Anyway... we come out of the longest month and jump straight into the shortest month. Feels like it doesn't make much sense. What's more, it's never made sense why February only has 28 days. I always knew it had something to do with the Romans, but I figured it was a way of saying nobody knew. You know... when you need an explanation for anything, just say it dates back to Roman times.
 
Thing is, this story actually does date back to Roman times. It really was the Romans who gave February 28 days. My trusty search engine tells me that the first king of Rome made up a calendar with just ten months. Word is he didn't put anything between December and March because winter wasn't a big time for the harvest.
 
Then the second king of Rome took power and wanted to make some changes. (Trust a politician to change the very calendar itself, just to show everyone that he's the boss man now.) He wanted the calendar to line up to the lunar calendar which has 354 days. And that meant he needed to add two extra months.
 
And now things get super sketchy in the history books. I'm totally confused, but I think it has something to do with the fact that each new month had 28 days, and even numbers were considered unlucky so 28 was a no-go. So he added a bunch of days but they all went into January. And somehow February got stuck with its 28 days, and nothing more.
 
Then Julius Caesar did something, something. For some reason he added some more days to get to a total of 365. But somehow February still got landed with just 28 days. And then stuff happened and centuries went by... and now our February as we know it still has 28. (Hey, I never said I was a historian, and I told you it gets complicated...)
 
And there you kinda have it. Romans. Caesar. Responsible for so much. Made our calendar. Just like I said, a politician is a politician. My theory is they did it because they were typical politicians – determined to confuse the life out of us.
 
So happy February. Make the most of these days because you've only got 28 of them. And hey, if you wanna know where leap years come from, please go ahead and ask someone else.