March/April 2020 Newsletter
COVID-19 AND YOUR EYES
Understandably, the global COVID-19 pandemic is the major topic on TV, in newspapers, on people's minds and in our daily conversations. As we try to make sense of it, countless questions are being asked and the answers come from a variety of sources and are often conflicting. Some of these questions relate to the eyes. Will COVID-19 affect my eyes? Will wearing glasses protect me from contracting the virus? Should I stop wearing contact lenses?
WILL COVID-19 AFFECT MY EYES?
Conjunctivitis ("pink eye") has been found to occur in 1-3% of people with COVID-19. Conjunctivitis is an inflammation of the transparent membrane covering the eye. It is characterised by red itchy eyes, accompanied by a watery or yellow discharge. It is contagious but is generally self-limiting with no long-term consequences for the eyes or vision. If you do have the symptoms of conjunctivitis contact your optometrist.
There is no evidence to suggest that wearing glasses or sunglasses offers protection in areas where there may be exposure to the coronavirus. To some extent they could decrease the number of times we touch our eyes, one of the suggestions to limit the spread of the virus.
Just like washing our hands regularly with soap and water, it is essential to clean our glasses thoroughly and dry them with a clean cloth. Make sure that your glasses case is clean and even sanitised. If using an antibacterial sanitiser to wash your hands, it can be used on the temples and bridge of glasses but avoid contact with the lenses.
Older people are a vulnerable group, and they may be putting on and taking off reading glasses frequently during the day, touching their faces each time, particularly whilst doing shopping. They should ensure that their hands and glasses are clean and sanitized when they get home.
It is not necessary to stop wearing contact lenses during this time. Although not a new recommendation, wash your hands carefully before inserting and removing your lenses. The importance of adhering to good hygiene practices is fundamental to maintaining eye health. Diligently follow the instructions given by your optometrist.
Soap and water is the preferred option when washing your hands, although an antibacterial hand sanitiser can be used. The problem with hand sanitiser is that the alcohol could get into your eyes via the lenses and lead to discomfort.
Daily disposable contact lenses should be disposed of every evening as usual. Weekly or monthly lenses should be disinfected regularly as per your optometrist's directions.
If you have dry eyes and use artificial tears or other eye drops, continue using them, again ensuring that your hands are thoroughly washed before inserting the drops. Stopping their use could increase irritation of your eyes, causing you to rub or wipe them more frequently which is contrary to the instruction not to touch the face or eyes.
STAY SAFE. STAY WELL. LET'S FLATTEN THE CURVE TOGETHER.
EYE-QUIT! A CLEAR-EYED REASON TO STOP SMOKING
The harmful effects of smoking on the health of the body are well-known. It comes as no surprise that smoking has been linked to eye disease, too. When we take a puff of a cigarette or exhale smoke, the smoke wafts upwards towards the eyes, making them water, burn, look red and feel gritty. While these effects are temporary and last only as long as the smoke exposure does, it is the toxic chemicals that are inhaled that cause lasting damage, travelling from the lungs to other parts of the body through the blood stream, and leading to biological changes in the body and the eyes. A number of chronic eye conditions are linked to smoking.
Dry eye is characterised by itchy, watery eyes, intermittent blurring of vision and a burning sensation in the eyes caused by insufficient tear production and/or poor tear quality. While it does not typically cause permanent vision damage, it is consistently irritating and uncomfortable. Exposure to smoke exacerbates the discomfort, but, more seriously, the tobacco chemicals interfere with the production of tears.
It has been found that there is a direct link between smoking and the development of cataracts, the clouding of the eye's naturally clear lens. Symptoms of cataracts include blurry vision, difficulty seeing at night or in low light, and the appearance of colours as faded or dull. Smokers have been shown to have twice the risk of developing cataracts as non-smokers.
AGE-RELATED MACULAR DEGENERATION (AMD)
Smoking is a key risk factor for AMD, with smokers developing the condition on average 5 years earlier than non-smokers. AMD is a deterioration of the macula, the sensitive central area of the retina at the back of the eye which is responsible for central vision. Tobacco interferes with blood flow and causes oxidative stress, reducing the amount of oxygen and nutrients reaching the macula, gradually destroying central vision and resulting in distorted or blurred vision, blind spots and eventually vision loss. Research has shown that giving up smoking reduces the risk of macular degeneration.
Diabetic retinopathy is a progressive eye condition caused by uncontrolled elevated blood sugar levels which damage the blood vessels of the retina. The blood vessels break down, leak or become blocked, injuring the retina and permanently affecting vision. Smokers who also have diabetes risk developing diabetic retinopathy, and if they already have it, it may progress more quickly than in non-smokers.
Smoking can increase the risk of developing glaucoma, a condition typically caused by elevated pressure within the eyes. Glaucoma causes a gradual break-down of the optic nerve which is responsible for transmitting visual information from the eye to the brain where it is processed. As the nerve cells die, vision is slowly lost. Once damaged, the optic nerve does not heal; vision loss is permanent and irreversible.
SMOKING DURING PREGNANCY
Smoking during pregnancy may harm the unborn baby's vision. It increases the risk of premature birth, which in turn increases the risk of the baby developing retinopathy of prematurity, an eye disease in premature babies characterised by abnormal blood vessel growth in the eye that can progress to vision loss.
The uvea is the middle layer of the eye which is rich in blood vessels carrying blood and nutrients to the eye. Uveitis is inflammation of the uvea causing it to become red, swollen and painful, and interfering with the flow of blood. It can damage the retina and the iris, exacerbate other eye conditions and result in vision loss. Toxins in cigarette smoke can cause tissue inflammation, doubling the risk of smokers developing uveitis.
Graves' disease is a condition which affects the thyroid gland. Bulging eyes may be one of the symptoms, and this can become worse in smokers.
CONTACT LENSES AND SMOKING
Smokers who wear contact lenses are twice as likely as non-smokers to suffer from dry eyes, which may cause them to experience increased ocular irritation and discomfort with their contact lenses. Their risk of developing corneal ulcers is raised.
Many non-smokers experience irritation from secondhand smoke, but the effects may be more damaging than annoying, particularly for young children who have been found to show signs of smoke-related health problems, both in the body and in the eyes. New research suggests that secondhand smoke may damage children's eyes and possibly lead to problems with vision later in life.
WORLD NO TOBACCO DAY ON 31ST MAY IS AN OPPORTUNITY TO "BE A QUITTER"!
For "2020: The Year of the Eye," the American Academy of Ophthalmology intended to list 20 vision-healthy foods. Instead, they came up with 36! It is widely believed that failing eyesight is an inevitable aspect of aging, but it has been found that a healthy lifestyle, which includes a healthy diet, can significantly reduce the risk of problems with the eyes. In fact, the same diet that enhances heart health and general well-being will help the eyes. Just as the heart relies on larger blood vessels, the eyes rely on tiny arteries for oxygen and nutrients.
Many studies on age-related eye disease agree that certain specific nutrients are vital for eye health. These include zinc, copper, vitamins A, C and E, beta carotene, omega 3 fatty acids, lutein and zeaxanthin. While some nutrients keep the eyes healthy, some have been found to reduce the risk of developing eye diseases.
LEAFY GREEN VEGETABLES
Lutein and zeaxanthin are antioxidants found in high concentrations in the macula, the centre of the retina which is responsible for central vision. They are believed to protect eye tissues from sunlight damage and reduce the risk of cataracts and macular degeneration. The body does not naturally produce enough of these nutrients that it needs so it is important to include them in the diet. Leafy green vegetables that are rich in these antioxidants include spinach, kale, broccoli and peas. The body needs fat to absorb lutein and zeaxanthin, so it is best to eat them with healthy fat such as avocado or a drizzle of olive oil.
ORANGE-COLOURED FRUITS AND VEGETABLES
Vegetables such as carrots, pumpkin, squash and sweet potatoes are rich in beta carotene, which gives them their colour. Beta carotene is converted by the body into vitamin A, which helps protect the surface of the eye and is essential for combating eye dryness, maintaining good vision and decreasing the risk of vision loss due to macular degeneration and cataracts. Similar to lutein and zeaxanthin, beta carotene and vitamin A are absorbed best when eaten with healthy fat.
FOODS TO HELP US "C" BETTER
Vitamin C is critical to eye health. As an antioxidant, it helps protect the body from unhealthy lifestyle and environmental factors, which produce free radicals that can damage cells in the body. Vitamin C helps the body repair and grow new tissue cells and fight age-related eye damage, such as cataracts and macular degeneration. Citrus fruits, strawberries, tomatoes, apricots and certain vegetables are vitamin C-rich foods.
NUTS AND LEGUMES
Vitamin E is an antioxidant which keeps cells healthy and can protect the eyes from age-related damage. It is found in avocados, almonds and sunflower seeds. Other nuts and legumes which help maintain eye health include walnuts, cashews, lentils, and chia and flax seeds.
Studies have found that a diet rich in omega-3 fatty acids enhances tear function and may help to alleviate dry eyes and reduce the risk of developing eye disease later in life. Many fish are rich sources of omega-3 fatty acids, but the fish that contain the most beneficial levels of this nutrient are oily fish, for example salmon, tuna, trout, anchovies and sardines. Salmon is also a good source of vitamin D which helps protect the eyes against macular degeneration.
MEAT AND BEANS
The mineral zinc has been linked to long-term eye health by keeping the retina healthy and protecting the eyes from the damaging effects of light. The eyes themselves contain high levels of zinc, particularly in the retina and blood vessels surrounding the retina. Excellent food sources of zinc include beef, chicken, turkey and pork. Zinc can lower the amount of copper in the body, a mineral which is needed to help form red blood cells. Fortunately, zinc and copper can be increased together by including a variety of beans, such as kidney beans and lima beans in the diet.
Eggs contain high levels of lutein and zeaxanthin, as well as zinc and vitamins C and E, all of which have an important role to play in minimising the risk of developing eye disease.
Maintaining hydration is essential for the whole body and can be particularly beneficial in reducing the symptoms of dry eyes. Drinking plenty of water to keep the body hydrated is important but green tea may be even more helpful in lowering the risk of developing cataracts and macular degeneration. Green tea contains catechins which have antioxidant and anti-inflammatory properties. Other foods high in catechins include dark chocolate, red wine, berries and apples.
Is it advisable to take nutritional supplements? This is a difficult question which does not have a simple answer. Generally, it is believed that a healthy balanced diet can provide adequate nutrition, but certain people are unable to absorb the necessary nutrients from their diet or are on a restrictive diet, while others question the nutritional quality of our food. It is best to discuss these issues with a health care professional. Taking a specific supplement for macular degeneration is frequently recommended by eye care professionals.
While these foods have been separated into different categories according to the nutrients they contain, many foods contain a number of important nutrients and their benefits overlap. The key is to eat a balanced diet of various foods with varying nutrients. As one expert expressed it: "Eat a rainbow!" Most importantly, remember that it is never too late to start eating healthy!
WHAT COLOUR IS THAT?
Colour blindness is a condition that is often misunderstood. The name implies that colour blind people are unable to see colour and can see only black and white, but this is not true. A more accurate term would be "colour vision deficiency" because people are able to see colour but they see a much narrower range of colour. It is estimated that with normal colour vision, people can see up to one million shades of colour, while people with colour vision deficiency may see only about ten thousand shades. To the normally sighted person, a rainbow features all seven colours. For many colour blind people, however, a rainbow only appears to have two or three colours.
HOW WE SEE COLOUR
The retina has two different types of cells, called photoreceptors, that detect and respond to light. These are the rods and cones. On average, we have about 110 million rods, which are activated in low or dim light, and 6 million cones, which are stimulated in brighter environments. Cones contain photo pigments, or colour-detecting molecules. Colour is not inherent in objects; rather, the surface of the object absorbs some colours and reflects others. The reflected colours enter the eye, are picked up by the photoreceptors on the retina, and sent via the optic nerve to the brain which processes them and interprets them as the sensation of colour. Cones are sensitive to red, green and blue light. If only the rods are activated, we see only shades of grey.
WHAT IS COLOUR DEFICIENCY?
Colour deficiency is an inherited condition that is thought to affect 300 million people throughout the world. It affects 1 in 12 males and 1 in 200 females. Usually, the condition is carried by the mother and passed down to her son. Babies are born colour blind. As they grow, their colour vision improves and is typically fully developed by the age of 6 months.
When the cones have all the various pigments, called photopigments, the eye sees all possible colours. Colour vision deficiency is caused by a change or reduction of sensitivity of one or more of the photopigments, resulting in colours not being perceived as they should be. Sometimes there is less sensitivity to some colours than to others, and sometimes certain colours cannot be perceived at all.
TYPES OF COLOUR VISION DEFICIENCY
Perception of colour is more subjective than objective. Because it is learned and based on each individual's subjective perception and past experience, it is not possible to be completely sure how the world of colour is seen, whether by people who have colour deficiency or not. However, it is possible to differentiate the various degrees and types of colour deficiency.
Red-green colour deficiency is the most common form of colour deficiency. It is characterised by confusion between all colours that have some red or green in them. More rarely, sufferers have a reduced ability to see blue and yellow hues. Achromatopsia, also known as "complete colour blindness", is the only type that fully lives up to the term "colour blind". It is extremely rare, and those who have achromatopsia only see the world in shades of grey, black and white, and may be extremely sensitive to light.
LOOKING THROUGH COLOUR DEFICIENT EYES
Colour confusion can manifest in many everyday situations that people without the condition take for granted. The frustration of a mismatched outfit, questionable paint choices, difficulty interpreting colour coded information, and being unable to determine whether fruit is ripe or food is cooked are just a few examples. Drivers with colour deficiency often judge traffic lights by their position rather than their colour but may have trouble if the lights are oriented differently, for example side by side or high above an intersection. On the sports field, the difficulty assessing the distance or pace of a fast-moving ball on green grass may influence the response of a player with colour deficiency.
Being colour deficient can impact career choices, because it could be a handicap, for example, for an electrician, a pilot, a doctor, a painter, a chef, a web designer, a florist, and many others in which the accurate perception of colour plays a critical role.
"Blindness to one's color blindness is common," remarks one expert, as many people are unaware that they do not experience colour as other people do. There are tests that are performed by optometrists to determine what type of colour deficiency a person has. While certain promoters of glasses with specific colour filters claim that the glasses enhance the colour signal and help make colour vision deficiency less stressful for sufferers, further evidence is needed. Most people with colour vision deficiency have learnt to adapt to their condition.
CHANGE THE WAY YOU SEE THE WORLD
A contact lens is a thin lens placed directly on the surface of the eye and is a comfortable convenient alternative or addition to wearing glasses. Leonardo Da Vinci is frequently credited with introducing the idea of contact lenses in 1508, although his methods were not practical. Modern contact lenses have been in use for decades, and the technology is constantly changing and developing as manufacturers realise the need to improve the comfort, safety and vision needs of contact lens wearers. With these significant developments comes the assurance that there is a contact lens solution for each of the 150 million contact lens wearers worldwide.
Contact lenses are very versatile and are a good choice of vision correction for people who enjoy an active lifestyle, who want to look and feel more natural or who want a full field of vision wherever they look. There are a number of different options available for different vision conditions.
CONTACT LENSES FOR REFRACTIVE ERRORS
A refractive error occurs when the eye cannot accurately focus the light entering the eye, resulting in blurred vision. The most common refractive errors are myopia (shortsightedness), hyperopia (farsightedness), astigmatism and presbyopia, which is generally associated with aging.
For people who are shortsighted or farsighted there are numerous options, including hard or soft contact lenses. Most people choose to wear soft contact lenses which are generally more comfortable. There are a number of soft contact lenses to choose from. Daily wear contact lenses are worn on a daily basis and removed at night. Within this category are various disposable lenses which, as their name implies, are thrown away after use. The advantage of disposable lenses is convenience, no need for cleaning solutions, and a reduced risk of infection, but they can be expensive. Extended wear contact lenses can be worn while one is sleeping but need to be removed for cleaning at least once a week. They come with an increased chance of infection.
Gas-permeable lenses are the most common type of hard lenses. They are made of a stiff but permeable material which allows oxygen to connect with the surface of the eye. Due to their rigid nature, they may take time to adjust to, they need to be disinfected every day and should not be slept in. They are often preferred by people who have allergies or tend to get protein deposits on their soft contact lenses.
People with astigmatism have an unusual eye shape, and that shape can lead to blurred vision at all distances. Toric lenses are specifically designed for astigmatism. They differ from regular contact lenses in that they have different powers in different meridians and there is only one correct way to wear them. Rigid gas-permeable lenses are particularly helpful with astigmatism.
Traditional contact lenses are made to correct just one type of vision issue, but presbyopia, which is associated with aging, presents a different challenge. For example, a person may need a prescription for distance vision as well as one for close work. A simple solution could be to wear reading glasses over contact lenses for near vision, but some people prefer not to have the added inconvenience of glasses. There are contact lens options which deal effectively with both issues. Monovision involves the use of single-vision lenses to focus one eye for distance vision and the other for near vision. The brain then learns to see clearly at all distances. Multifocal contact lenses are comparable to glasses with bifocal or progressive lenses, in that they have prescriptions for both distance and near vision and are designed to provide a gradual transition between the two.
A scleral contact lens is a large firm contact lens that rests on the white of the eye, the sclera, rather than covering only a portion of the cornea. All modern scleral lenses are made with highly breathable, rigid gas permeable lens materials so that, although they cover the entire cornea, plenty of oxygen reaches the front surface of the eye to keep it healthy and comfortable. Scleral lenses may also be used to improve vision and reduce pain and light sensitivity for people suffering from disorders or injuries to the eye, such as severe dry eye syndrome, irregularly shaped corneas due to keratoconus, complications following eye surgery as well as discomfort wearing conventional contact lenses.
THERAPEUTIC SOFT LENSES
Soft lenses which do not have a prescription built into them are often used in the treatment and management of non-refractive conditions of the eye. A bandage contact lens allows the wearer to see while protecting an injured or diseased cornea from the constant rubbing of blinking eyelids. They may be used in the treatment of conditions including dry eyes, corneal abrasions and erosion, keratitis, corneal edema, chemical and burn injuries among others.
PHOTOCHROMIC CONTACT LENSES
Photochromic contact lenses are contact lenses that work in a similar fashion to photochromic glasses and are of particular benefit to people with light sensitivity. They appear clear indoors, gradually darkening when exposed to sunlight. While not intended to replace sunglasses, they do offer comfort to people who find bright light and glare disturbing, as well as providing some protection from harmful ultraviolet (UV) rays and the blue light from LED screens.
LENSES FOR COLOUR VISION DEFICIENCY
There is no cure for colour vision deficiency or colour blindness, as it is commonly known. However, some manufacturers claim that using special tinted glasses or wearing a red-tinted contact lens on one eye may increase some people's ability to compensate for missing colour filters in the eye and help them to differentiate between certain colours. Further evidence is however needed.
COLOURED CONTACT LENSES
Coloured contact lenses may be simply cosmetic to change the appearance of the eyes, or they may contain a prescription to correct a refractive error as well. Cosmetic lenses need to be treated like all contact lenses to avoid the risk of infection – they should be prescribed by an optometrist, cleaned regularly as directed by the optometrist, not be shared with others and definitely not bought at markets or party stores. Some coloured contact lenses completely cover the iris dramatically changing eye colour, while others merely tint the iris, highlighting the natural colour of the eyes.
CONTACT LENSES AND TECHNOLOGY
Contact lens technology is a fertile area of ongoing research with new developments emerging at a rapid rate. To provide medical professionals a means to monitor and manage their patients' health, some companies are working on contact lenses which will display information related to chronic medical conditions, such as glucose levels in diabetes and elevated eye pressure in glaucoma sufferers. Others are researching contact lenses which can deliver medication, for example eye drops that need to be inserted regularly or antihistamines to people with allergies. Telescopic lenses could help those with macular degeneration move between normal and magnified vision literally in the blink of an eye! A similar effect could be obtained with auto-focusing contact lenses.
Augmented reality is the ultimate demonstration of how technology can change our perception of the world. In the near future we could be experiencing augmented reality through our contact lenses, allowing us to display images, play videos and open web browsers right in our line of vision. We could be taking photographs just by blinking, creating maps in front of us as we walk, and seeing objects, once blurry in the foreground, come into focus. Science fiction or a likely reality?
THROUGH DIFFERENT EYES
Talk about seeing the world through new eyes. Not long ago, we celebrated the beginning of a new decade. To many, it felt like the dawning of a new era. And suddenly, here we are. Sitting inside our homes for 21 days.
I'm not about to ignore the seriousness of the situation, or put a happy face on a major international crisis. But since we're in this anyway, what if we could grasp the opportunity to put on new glasses (or new eyes), and see things from a fresh perspective?
I mean, this is the perfect chance to see your partner/family/housemate through different eyes... hopefully good ones. Hopefully we'll find new things to love about each other. Hopefully it won't matter that they leave dishes in the sink and half-empty coffee cups all over the place. Hopefully we won't mind that they breathe weirdly while they work. Hopefully we won't reach a stage where we're drawing lines on the floor to mark out Your Side and My Side.
See, we all have those meaningless little habits that would be annoying to the people living with us. Only they're not really, because we only enact them for a few hours every day. The rest of the time, we're inflicting those habits on our co-workers as they inflict theirs on us. Now? It's all day, every day.
But let's stay on track and keep things positive. (Fresh optimistic eyes, remember?) Staring at your four walls could help you see your home in a completely different way.
There's a story going around about how Swiss shops have no stock on their shelves. No, not their supermarkets - their hardware stores. The people of Switzerland are embracing this chance to complete all the DIY tasks they've been putting off. They figure they've finally got some time on their hands. When all this is over, House & Leisure will have to dedicate an entire issue to Switzerland's newly-fabulous homes.
Now that's what they mean when they talk about seeing the opportunity in the crisis. Seeing the silver lining and all that. So maybe it's time to grab that To-Do list. (No, not the one you made... the one your spouse made for you.)
Ever the optimist, my estate agent friend has a brilliant marketing strategy in mind. When shutdown is over, she's going to send out a flyer that says: "Tired of your house after 21 days inside? Time to buy a new one!" (True story.)
As the world starts to look different, maybe we'll start to feel different too. No traffic means no road rage. No gym means no frustration with those people who hog three machines at a time. Lockdown means no rushing to meetings. No rushing anywhere, in fact.
Again, these are challenging times. But what if it all ends and we discover we've become... nicer?
And how will everything look once we step outside again? Maybe the same. But maybe, not quite.