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Why wear cycling sunglasses? Besides looking good (or goofy, eye of the beholder and all that), cycling sunglasses shield your eyes from bright sunlight and harmful UV rays, and also offer protection from the wind, rain, dust, grit and bugs that can impair your vision.

Cycling eyewear's not just for looking cool; it protects your eyes from harmful UV light and flying insects, dust and other crud.

Cycling sunglasses usually cover more of your face than fashion eyewear for better protection, and use tougher lenses.

Many manufacturers offer interchangeable lenses so you can tailor your cycling sunglasses for the conditions.

Photochromic lenses automatically darken in bright sunlight so you can use the same glasses in a range of conditions.

Need prescription cycling sunglasses? Most top eyewear makers offer them; ask your optometrist.

What should you look for in a pair of cycling sunglasses? Well they differ from regular sunglasses in that they have a wraparound design so they sit closer to your face. The frames are usually thinner and they're made from lightweight and durable materials, and the lenses are lighter too, typically shatterproof and they come in a vast rainbow of tints to suit different lighting conditions.

> On a budget? Read our roundup of the best cheap cycling sunglasses with glasses from 9.49> Looking for a bargain? We've found half a dozen great deals where retailers have cut up to 61% off their glasses.

Fit is the key criterion when choosing a new pair of cycling sunglasses. They need to be comfortable with no pinch points or excessive tightness, and they need to sit close to your face and not obscure your vision. Some manufacturers offer sunglasses in a narrow design or a women-specific fit, but the vast majority of cycling sunglasses are unisex with a one-size-fits-all design. For that reason, it's always a good idea to try some on before you buy and choose the glasses with the best fit.

Fit can sometimes be adjusted to preference. Some cycling sunglasses have adjustable arms and nosepieces that can tailor the fit, and some have interchangeable rubber parts that can customise the fit even further. You want the sunglasses to be stable so they dont bounce around or slip forward. The rubber contact points will help the glasses stay put when you sweat a lot. Generally, a sign of good fit is that you forget you're wearing them when you're cycling.

Arms can be flexible or rigid, Most are covered with a rubber material to grip your head and stop them moving about. When you're trying on a pair of glasses, it's worth doing so with your helmet on, as some glasses can foul the straps and retention systems of some helmets. The nose piece can either be fixed or adjustable, some glasses come with several differently sized rubber nosepieces so you can get the fit just right.

Lenses come in a huge range of tints and colours from dark black to protect your eyes in bright sunlight, to yellow for boosting contrast in poor light. Clear lenses are good for riding at night. There's now so much choice that it can be a little bewildering picking the right lenses for the particular conditions.

You need to choose a lens that matches your riding requirements. Many cycling sunglasses have a fixed lens, so you're stuck with whatever lens come with the sunglasses. Cycling sunglasses with interchangeable lenses are common these days, and very popular, for good reason. Choose a pair of glasses with several sets of lenses and you are going to be prepared for most typical cycling conditions.

Some manufacturers make photochromic lenses that get lighter or darker according to the conditions, but the range they offer is more limited at present than specific lenses, but can be a useful and appealing alternative if you don't want to have to worry about changing lenses.

Some lenses are vented or have an anti-fogging coating to help reduce fogging when you sweat. Some manufacturers apply a hydrophobic coating to help rain run off the glasses. You also want to make sure the lens has UVA and UVB protection. Some cycling sunglasses offer a prescription option, either with the sunglasses lenses made to your prescription or with clip-in lenses behind.

The price you can expect to pay for cycling sunglasses varies hugely. What does paying more money get you? The biggest difference is in the lens. The best cycling sunglasses boast very high quality optics that provide exceptional clarity, and you often have a wider range of tints to choose from.

The extra money often gets you a lighter weight frame and often more fit adjustment. You can expect extras like spare lenses to suit different conditions, hard-shell cases to store them in as well as soft fabric bags cleaning the lenses and storing the glasses when they're not in use.

Lets not forget that as well as performance, cycling sunglasses are also a fashion item, and looks are an important consideration for many. Cycling sunglasses are available in a massive range of designs and colours and there's something for all tastes and styles. But we'll leave that bit to you.

The Flywheel from Smith Optics are retro/modern-looking sunglasses featuring Smith's own tinted ChromaPop lenses. Theyre light, comfy and give excellent coverage for riding. Although downsides are few, the lens isnt interchangeable, meaning they're only really useful for spring and summer.

These semi-framed glasses are made from a very flexy thermoplastic (TR90) and feature auto-lock hinges and adjustable two-position nose pads. The pads are hydrophilic, by which Smith mean they stay grippy instead of getting slippery as the sweat starts flowing.

The lens uses Smith's ChromaPop technology, which filters two wavelengths of light the company claims 'cause colour confusion.' The aim is to boost your ability to see clearly, and the darkened lens gets a hydroleophobic coating to further help things.

Read our review of the Smith Optics Flywheel glasses

The 100% S3 MAAPs are lovely big sunglasses that provide excellent coverage and great clarity. They're comfortable to wear and secure on the face, though the style won't be for everyone. Big glasses are getting very common, especially among younger riders, and the S3 is a great example of why the increase in size is great for cycling.

The size of the lens means there is no frame getting in the way of your view. This is great for racing and bunch riding as you still get unimpeded lines of sight when hunched down in the drops.

Clarity on the road is really good, with a nice amount of contrast boost to make the world look much nicer on a grey day. The most challenging conditions for sunnies is bright sunlight after heavy rain, as this causes a lot of glare. The S3 deals with these conditions brilliantly: while the road was still bright, I was easily able to see potholes.

Read our review of the 100% S3 MAAP glasses

The very good quality Julbo Rush Reactiv sunglasses have a quick-reacting photochromic lens and are comfortable to wear, while offering a great field of vision. You can buy cheaper, but they hold their own in expensive company.

Like most things in the road cycling world, fashion heavily dictates what sunglasses we are wearing, and at the moment everything is getting bigger. The Rush Reactivs follow that trend.

The clarity of the Julbo's lens is very good, with no distortion as it curves around your face, and there's no refraction from car headlights when wearing the glasses in the dark.

The Reactiv lens found on this model is photochromic, so it reacts to changes in the amount of light outside. With a light transmission rate of between 12% to 87% this natural coloured lens with a smoked tint when activated is spot on for year-round use, whether day or night.

Read our review of the Julbo Rush Reactiv glasses

Galibier's Surveillance Precision Optics glasses offer excellent all-round vision for a full-framed pair of shades. They're lightweight and very comfortable to wear, and they're flipping cheap too.

On test we've had two of the three available options of Surveillance glasses, the Matt Black with Smoke Plasma Mirror lens (37), and the TortoiseShell frame with a Gold Plasma Lens (42). If you want a polarised lens then this is available in a Gloss White frame, also 42.

Both Plasma lenses are designed to be used in medium to bright light, with the black framed option offering truer colour perception in sunny conditions, while the Gold version on the TortoiseShell has a coating to increase contrast by filtering blue light and reduce glare. Both work brilliantly with really clear optics and no distortion whatsoever.

Read our review of the Galibier Surveillance Precision Optics glasses

With little to no fogging, good eye coverage and an unobstructed field of vision, Rockrider's XC Race Photochromatic glasses deliver a strong performance for their low price. The light-sensitive tinting works really well too, which is good it saves you using the flimsy lens-swapping mechanism.

At 39g, the XC Races are barely noticeable thermonuclear colouring aside once on. Coupled with an unrestricted view, they're a very unobtrusive bit of kit once in action. The only time I did notice them was, in fact, thanks to the neon yellow nose piece catching my eye, and there isn't another colour frame option in the range that is still photochromatic.

Rubber grippers at the ends of the arms and across the nose keep them firmly in place, wet or dry. More impressive is their resistance to fogging up, even when provoked. They can cloud over on slow, steep climbs in mild and damp conditions, but clear quickly once you move a bit faster.

Read our review of the RockRider XC Race Photochromatic sunglasses

The Rudy Project Defenders are an impressive pair of glasses, with the photochromic lens especially impressive in changeable conditions. They provide great protection, but the price will put some off.

Photochromic lenses have become increasingly popular in recent years, but can suffer by being slow to change. With the Rudy Project Defenders, changes happen rapidly enough that you don't instantly feel plunged into darkness, but equally don't leave you feeling like you're staring directly at the sun.

They go from essentially non-prescription clear lenses to dark black, and adjust to every light between, meaning you can always maintain a clear view of what's on the road in front of you. They also have impressive clarity and strong peripheral vision, despite being full frame glasses.

Read our review of the Rudy Project Defender ImpactX Photochromic 2

With fashion dictating that cycling shades return to the ski goggle shapes and sizes of the 90s, the Boll Shifter glasses are bang on trend, but they aren't form over function thanks to excellent visibility and sharp optics. Even though they are a fully framed pair of glasses, not one part of it gets in the way of your eyesight.

The lens wraps further round the side of your eye than most glasses with a frame, which means that when glancing over your shoulder or looking left or right you have full visibility. You can see the frame but it's positioned just far enough out of your line of sight.

Read our review of the Boll ShifterFind a Boll dealer

Decathlon's Rockrider ST 100 glasses previously known as Orao Arenberg are light, comfortable and cost less than a coffee and slice of cake. If you can put up with the inevitable 'safety glasses, aren't they?' jibes, you're quids in over the eye-candy brigade.

The ST100sare available with clear lenses, and also a yellow and a grey for overcast/foggy and bright weather respectively. All three are made from 100% UV-blocking impact-resistant polycarbonate.

Read our review of the Rockrider ST 100 glassesFind a Decathlon store

These are good value with clear, scratch-resistant lenses, and the ergonomic shape provides a particularly wrapped feel. The lenses have been treated to make them perfectly smooth to allow any water to slide off, keeping your vision clear.

You can also get them with polarising lenses, which help reduce glare from reflective surfaces, for 22.99.

Read our review of the Northwave Predator

A really popular model, these DArc glasses have a classic half-frame wraparound design and theyre supplied with three lenses to suit different conditions. They have a single lens design for maximum protection and the frame is coated with a rubberised material to provide a comfortable and non-slip fit.

Find a Madison dealer

These offer great style and impressive value for money, and the lightweight Grilamid plastic has a good degree of flex to allow them to fit different head sizes. The hinges have a nice smooth action and the rubber nosepiece is adjustable. A nine-layer coating gives the MLC blue tinted polycarbonate lens (pictured) great contrast in a range of lighting conditions, and the lenses are relatively easy to swap.

Read our review of the BBB Select Sport glassesFind a BBB dealer

The Tifosi Dolomites 2.0 are a strongly performing pair of glasses that allow for a good level of ventilation around the nose and ears, without being too breezy. We found that the lenses were both easy to fit and secure in the sturdy frame.

We've generally been impressed with Tifosi glasses; they're usually very good quality for their modest price. If the Dolomites don't quite float your boat take a look at the Radius FC glasses and the Talos model.

Read our review of the Tifosi Dolomite 2.0 sunglassesFind a Tifosi dealer

Lightweight, comfortable glasses with two lenses and a hard case included in the sensible price. The lightweight frame is made from a Grilamid material. You notice the lack of bulk when you first extract them from the hard case. You get two lenses in the hard case, a tinted multi-layer mirror coating lens and a low-light orange lens.

Read our review of the Salice 011 RW sunglasses

The Tifosi Davos Interchangeable Lens glasses offer good clarity, a wide field of vision and decent venting, although it would be nice if changing the lenses was a little less fiddly. Nevertheless, they're well made, and light.

When conditions are changeable it's important to have glasses that can adapt to the different lighting while also having good venting. The Davos, with their three lenses, are a good option. There are three colours included in the package: clear, AC red and smoke. These are each made of Grilamid TR-90, which according to Tifosi offers high resistance to chemical and UV damage, high alternative bend strength, and low density.

Read our review of the Tifosi Optics Davos glassesFind a Tifosi dealer

Although BBB's BSG-50 Summits are mid-range models, they're really good glasses and pack in a number of innovative features. One of the most important, and one that BBB is keen to promote, is the ease with which the lenses can be switched. In fact they excel here; aside from the high-end hinged Oakleys, they are one of the simplest to change that we have used.

It's good because you get three different lens colours with the glasses, with varying degrees of protection: full mirrored, yellow and clear. These lenses work really well and we were particularly impressed by their anti-fogging qualities, which works through a combination of anti-fog coating and very impressive ventilation on the top and sides of the lenses.

They're also available with photochromic lenses for about 110.

Read our review of the BBB Summit glassesFind a BBB dealer

Lazer's Walter full frame glasses offer very good performance and a certain amount of dashing '80s style. Because of that they've become a bit of a favourite.

Shape-wise, and with their full-frame, single-lens design, these Lazer glasses bear more than a passing resemblance to Oakley's Pilot Eyeshades of the mid '80s. They don't have the sweat-catching brow strip, but that always used to fall off anyway. They're a bit more angular, too, and not as big, but they certainly have a retro kind of a feel.

There's nothing retro about the materials or construction, though. The polycarbonate frame is light and tough, with adjustable, rubberised ear and nose pieces that make getting a good fit very simple.

The Walters come with three lenses. There's a low-transmission semi-mirrored lens for sun, a high-contrast lens for overcast conditions, and a clear lens for night-time. All three have a hydrophobic coating which is very effective: the water beads on the surface very well and taking them off and tapping them on the handlebar clears most of the rain.

Read our review of the Lazer WaltersFind a Lazer dealer

The NRC X1RR Blackshadow glasses certainly look the business with their gold details and lenses, and thankfully they deliver top drawer performance and comfort too.

The lens is made by Zeiss and it has done a very good job as I couldn't find a single flaw in them. There is no loss of sharpness, wherever you move your eyes, and thanks to having no actual frame your field of vision is completely unobstructed, allowing you to see everything that is happening in front and to the side of you.

Read our review of the NRC X1RR Blackshadow glassesFind an NRC Eyewear dealer

They're a shade expensive compared to some other manufacturer's light-reactive shades, but the Julbo Aerospeed photochromic sunglasses are a sophisticated and very well-made set of sports glasses. The lenses automatically adjust to changing light and offer CAT 1-3 ratings for ultra-violet protection. Better still, should a lens, arm or similar component break, replacements are readily available.

The lenses are made from NXT, a plastic originally developed for helicopter windscreens. Aside from being light and shatterproof it has the lowest distortion of any plastic so there's no bending of light or warped vision. Since the lens is cast, and so takes longer to produce than an injected type, this increases the cost.

The reactive element is activated by ultra-violet light and will steadily darken, from clear to a dark shade, in around 15 seconds. This is also cast into the lens, so cannot scratch, or otherwise deteriorate. The other features are pretty much what you'd expect from high-end sports sunglasses. The inside and outsides feature anti-fogging and water-repelling (hydrophobic) treatments and the frame is made from Rilsan G85 polyamide and features silicone grippers for a secure, unobtrusive fit.

Read our review of the Julbo Aerospeed photochromicFind a Julbo dealer

With an RRP of 139.99, the Pro Escalate FSH glasses set is the most expensive that Tifosi makes; the company is better known for its good quality mid-range riding specs. It's a really good set though: there are three frame options, six lenses and a nice case to keep them all in.

FSH stands for Full, Shield and Half, and that's what you get: a full frame, a shield frame where the lens itself is the frame and a half frame. Well, you don't get the three whole frames, there's just one pair of Grillamid TR90 plastic arms that snap onto whichever front you fancy wearing.

Read our review of the Tifosi Pro Escalate FSHFind a Tifosi dealer

The BZ Optics PHO Fluro Yellow Frame with Photochromic Bi Focal Lens is a fully featured item of sports eyewear, for people who need bi-focal assistance in all conditions from darkness to bright glare. For 99.99 with interchangeable lenses, they're a pretty good pair of goggles in their own right.

At first glance the PHOs look like any other pair of cycling glasses, albeit clear ones if seen indoors the first time. Clear lenses always run the risk of resembling safety specs, and in this regard the PHOs aren't wide of the mark particularly in fluorescent yellow ('graphite' and white are also available).

The near-ubiquitous design of a single top frame facilitates the changing of lenses, done via a nifty wee grey clip at the temple that pivots out to unlock things. We must confess we wore the PHOs for a month before realising the lenses could be removed, the mechanism is so well hidden and its hold on the lens so secure. Additional lenses are available in photochromic non-prescription and with a 'blue mirror' finish, and of course as a replacement should you damage the original lens. The 'Reader' lens with the bifocal bit is available in +1.5, +2 and +2.5 powers.

Read our review of the BZ Optics PHO Bi-focal Photochromic GlassesFind a BZ Optics dealer

These Rudy Project Fotonyk cycling sunglasses are perfect for riding any time of the year thanks to their photochromic lenses changing from clear to dark in reaction to lighting levels. With great optics, comfort and not the slightest hint of fogging, they are a joy to wear.

We did the bulk of our testing of these in winter, perhaps the toughest time of the year to choose which glasses you're going to stick on for the ride, leaving and arriving home in the dark but with that whole sunrise/daylight/sunset thing going on in between. This is where the Fotonyks come into play with their ability to become all-rounders; they're suitable for practically every eventuality.

The first thing you notice is the clarity of the lenses. Our tester swapped mid-ride from POC Blades to the Fotonyks and the difference was noticeable, the Rudy Projects being so much clearer and sharper. Even as the lenses curve around your face there is no distortion at all.

Read our review of the Rudy Project Fotonyk Black Matte GlassesFind a Rudy Project dealer

Aerodynamic fairings on a pair of cycling sunglasses? Yep, the Boll 6th Sense are about as pro as you can get, especially with our test set being in AG2R La Mondiale colours. It isn't all about gimmicks, though, as these glasses are seriously good.

The big lens of the 6th Sense has a retro look to it, harking back to visors of the Nineties, but as far as technology goes they are bang up to date.

The frame is practically non-existent, which is something we like. There is nothing worse than crouching down in the drops or doing a quick shoulder check to find that there is a piece of plastic in your line of sight. The 6th Sense offer a massive field of vision without you even moving your head.

Read our review of the Boll 6th Sense glassesFind a Boll dealer

Oakley's Jawbreaker Prizm Road glasses were developed in collaboration with Mark Cavendish, a sprinter renowned for his very low head position when racing for the line. Usually for the win. The downside to that sort of aggressive position is that the top of the frame on most cycling glasses obscures your line of sight, and the result is usually a sore neck from craning to see under or over the frame.

With the Jawbreakers, Oakley sought to increase the upward field of view. The result is that the top of the frame is much higher than most other eyewear we have ever tested. There's very little intrusion into your vision. It's very impressive. Get your chin down on the stem and assume an aggressive position, as you would when racing or time trialling, and the top of the frame really doesn't intrude into your vision at all.

Read our review of the Oakley Jawbreaker Prizm

Optilabs is a Croydon-based specialist sports optician that offers a range of eyewear, all of which are available with prescription lenses. They all offer 100% UV protection.

Read our review of the Optilabs Switch glasses

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28 of the best cycling sunglasses protect your eyes from sun, crud and flying bugs - road.cc

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Contact Us : Hector CostelloSenior Manager Client Engagements4144N Central Expressway,Suite 600, Dallas,Texas 75204, U.S.A.Phone No.: USA: +1 (972)-362-8199 | IND: +91 895 659 5155

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Global Automotive Recognition System Market Projected to Reach USD XX.XX billion by 2025- CogniVue, EyeSight Technologies, Intel, Qualcomm, Gestsure...

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In this latest research publication on the Gesture Control Interfaces market, a thorough overview of the current market scenario has been portrayed, in a bid to aid market participants, stakeholders, research analysts, industry veterans and the like to borrow insightful cues from this ready-to-use market research report, thus influencing a definitive business discretion.

The aim of the report is to equip relevant players in deciphering essential cues about the various real-time market based developments, also drawing significant references from historical data, to eventually present a highly effective market forecast and prediction, favoring sustainable stance and impeccable revenue flow despite challenges such as sudden pandemic, interrupted production and disrupted sales channel in the Gesture Control Interfaces market.

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Market segment by Type, the product can be split into Wearable BasedVision BasedInfrared BasedElectric Field BasedUltrasonic Based

Market segment by Application, split into Consumer ElectronicsAutomotiveGaming and EntertainmentHealthcareDefenseOthers

The report is targeted to offer report readers with essential data favoring a seamless interpretation of the Gesture Control Interfaces market.Therefore, to enable and influence a flawless market specific business decision, aligning with the best industry practices, this specificresearch report on the Gesture Control Interfaces market also lends a systematic rundown on vital growth triggering elements comprising market opportunities, persistent market obstacles and challenges, also featuring a comprehensive outlook of various drivers and threats that eventually influence the growth trajectory in the Gesture Control Interfaces market.

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About Us : With unfailing market gauging skills, has been excelling in curating tailored business intelligence data across industry verticals. Constantly thriving to expand our skill development, our strength lies in dedicated intellectuals with dynamic problem solving intent, ever willing to mold boundaries to scale heights in market interpretation.

Contact Us : Hector CostelloSenior Manager Client Engagements4144N Central Expressway,Suite 600, Dallas,Texas 75204, U.S.A.Phone No.: USA: +1 (972)-362-8199 | IND: +91 895 659 5155

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Global Gesture Control Interfaces Market Projected to Reach USD XX.XX billion by 2025- GestureTek, Gestigon, Leap Gesture, EyeSight Technologies,...

By Reneva Fourie Jul 6, 2020

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I am supposed to rest my eyes, but my eyes are refusing to remain closed, because they can see clearly for the first time.

I was born with a sight impairment. I thought that spectacles (and later contact lenses) had enabled me to enjoy perfect vision despite the impairment. I was wrong. Having had intraocular surgery in Damascus, Syria, everything is so vivid, that it appears abnormally large. The cost was a fraction of the price that South Africans pay for normal laser surgery.

During the month of June, the lenses in my eyes were removed and replaced with synthetic, multi-focal, intraocular lenses. The lenses were designed to address my inherent short-sightedness (myopia) as well as the normal retinal degeneration that human beings naturally develop as they age. It is anticipated that I will now have perfect vision for the rest of my life.

I had to have one eye done at a time, with two weeks between the operations. Although it has barely been a week since my second eye operation; my eyes have been at work ever since their implantation. Despite strict instructions to steer clear of activities that will strain them, all efforts to close them and focus on other things have been impossible as the difference in quality of life is overwhelming.

Only people with sight challenges will understand. Seeing is a tiring and stressful exercise for those who are visually impaired, no matter how mild. It requires tremendous effort, attention, and focus. The consequences are multi-fold. There are endless headaches. Your eyes tire easily so you always feel a need to rest them. And of course, you try and avoid things that require good eyesight because looking is simply exhausting.

One of the things that you avoid, is being around people too much.Depending on the degree of impairment, you cannot see people clearly unless they are right in front of you. And while one learns to recognise those closest to you by using other means, it takes a while to become accustomed to new people; and so you avoid people in general to save yourself the embarrassment of appearing arrogant.

Then, you always have bruises. You are always bumping into or falling over things, whether you are wearing spectacles or not and consequently the label of being clumsy develops and is internalised. Academically you develop an excellent memory because half the time you battle to figure out what was written on the board. Personally, I had almost no vision at night, and having to move anywhere beyond my bed always made me feel extremely insecure.

If those were my experiences, and I had forty percent of my sight, which is regarded as moderate visual acuity, I cannot even imagine what life must be like for those with severe visual acuity and those who are blind. According to the World Health Organisation (2018) at least 2.2 billion people have a vision impairment or blindness. More than a million South Africans are recorded as sight disabled. Eyecare however, is not an integral part of South Africas health care system.

About a decade ago, I explored undergoing a laser operation on my eyes. Despite belonging to a top-of-the-range medical aid, the medical aid refused to cover the costs because the operation was regarded as cosmetic. The price quoted at the time was more than I could afford. Laser operations in South Africa remain accessible only to an exclusive group. Multi-focal intraocular surgery is accessible to an even smaller group. In Syria, a far-more sophisticated operation than laser surgery cost me less than the quote given to me back then for the laser surgery.

Laser operations in Syria are common. Intraocular surgery in Syria is common. Everyone who needs it, have their eyes fixed, when they reach the appropriate age. The right to sight is a norm and, consequently, eyecare forms an integral part of the public health system. Public health care in Syria is free and even private healthcare is much more affordable than it is in South Africa.

South Africa has far-reaching legislation to accommodate persons living with disabilities. The obliteration of that which causes the disability, however, requires further discourse and effort. Given that the costs of eradication are far less than the costs of maintenance; and the tremendous improvement in quality of life, the highest consideration should be given to ensuring that the latest technology be made available and accessible to all those whom it can assist, regardless of income.

As the country prepares for the implementation of the National Health Insurance, it is important that eyecare forms an integral part of the services that will be provided. The right to sight is not a luxury; it is not cosmetic; it is an imperative.

* Reneva Fourie is a policy analyst specialising in governance, development and security and currently resides in Damascus, Syria.

** The views expressed here are not necessarily those of IOL.

See original here:
There shouldn't be a price tag on the right to sight - IOL

NORTH CHICAGO, Ill., July 9, 2020 /PRNewswire/ --Allergan, an AbbVie (NYSE: ABBV) company, today announced that the U.S. Food and Drug Administration (FDA) approved a supplemental Biologics License Application (sBLA) that supports expanded use of BOTOX for the treatment of spasticity in pediatric patients 2 years of age and older, including those with lower limb spasticity caused by cerebral palsy.

This label expansion is based on Allergan and another manufacturer selectively waiving orphan exclusivity marketing rights each company held for the use of their respective neurotoxins in the treatment of pediatric patients with spasticity caused by cerebral palsy. BOTOX was first approved in June 2019 for the treatment of pediatric patients with upper limb spasticity and in October 2019 for the treatment of pediatric patients with lower limb spasticity, excluding spasticity caused by cerebral palsy. BOTOX has not been shown to improve upper extremity functional abilities, or range of motion at a joint affected by a fixed contracture.

Spasticity is a debilitating neurological condition involving muscle stiffness that can result in tight muscles in the upper and lower limbs. The severity can range from mild to severe, often interfering with normal muscular movement and function. This can result in delayed or impaired motor development, as well as difficulty with posture and positioning. Common causes of spasticity in children include cerebral palsy, traumatic brain injury, multiple sclerosis, spinal cord injury, and stroke.

"Cerebral palsy is the most common cause of pediatric spasticity, which can have a profound impact on a child's development and quality of life. With its established safety and efficacy profile, we are pleased that BOTOX can now more broadly support physicians treating pediatric spasticity," said Mitchell F. Brin, M.D., Senior Vice President, Chief Scientific Officer, BOTOX & Neurotoxins, AbbVie."Building upon our 30 years of research and development efforts with BOTOX, our commitment to neurotoxin innovation continues, and it is particularly rewarding to bring forth new treatments to advance care for pediatric patients."

The safety and efficacy of BOTOX as treatment for lower limb spasticity for pediatric patients is supported by a Phase 3 study with more than 300 patients two to 17 years of age with lower limb spasticity because of cerebral palsy. These trials included a 12-week, double-blind study and a one-year open-label extension study.

Allergan is committed to providing resources and services, such as the BOTOX Savings Program, to help ensure BOTOX is accessible and affordable to patients.

About BOTOX

BOTOX is one of the most widely researched medications in the world, with a proven history as a therapeutic agent.1 First approved by the FDA in 1989 for two rare eye muscle disorders blepharospasm and strabismus in adults, BOTOX was the world's first approved botulinum toxin type A treatment. Today, BOTOX is FDA-approved for 11 therapeutic indications, including Chronic Migraine, overactive bladder, leakage of urine (incontinence) due to overactive bladder caused by a neurologic condition, cervical dystonia, spasticity, and severe underarm sweating (axillary hyperhidrosis). Backed by strong science and continuous innovation, BOTOX proudly embraces its past while boldly looking to the future.

BOTOX(onabotulinumtoxinA) ImportantInformation

IndicationsBOTOXis aprescriptionmedicinethatisinjectedintomuscles andused:

BOTOX is also injected into the skin to treat the symptoms of severe underarm sweating (severe primary axillary hyperhidrosis) when medicines used on the skin (topical) do not work well enough in people 18 years and older.

Itis notknownwhether BOTOXissafeor effectivetopreventheadaches in patientswithmigraine whohave14orfewer headachedays eachmonth (episodicmigraine).

BOTOXhasnotbeenshowntohelppeopleperformtask-specific functions withtheir upper limbsor increasemovementinjointsthatare permanentlyfixedinpositionbystiffmuscles.

Itis notknownwhether BOTOXis safeor effectivefor severe sweating anywhere other thanyour armpits.

IMPORTANT SAFETY INFORMATION

BOTOXmaycause serioussideeffects that can belifethreatening.Get medicalhelp right awayifyou haveanyoftheseproblemsanytime(hours toweeks) afterinjection ofBOTOX:

There has not been a confirmed serious case of spread of toxin effect away from the injection site when BOTOX has been used at the recommended dose to treat chronic migraine, severe underarm sweating, blepharospasm, or strabismus.

BOTOXmaycauseloss ofstrengthor general muscleweakness,vision problems,ordizziness withinhours toweeksoftakingBOTOX.If this happens,do notdriveacar,operate machinery, or do other dangerous activities.

Do not receiveBOTOXifyou:are allergic to any of the ingredients in BOTOX (see Medication Guide for ingredients); had an allergic reaction to any other botulinum toxin product such as Myobloc (rimabotulinumtoxinB), Dysport (abobotulinumtoxinA), orXeomin (incobotulinumtoxinA); have a skininfectionat theplannedinjectionsite.

Do not receiveBOTOXfor thetreatment of urinaryincontinenceif you:have a urinary tract infection (UTI) or cannot empty your bladder on your own and are not routinely catheterizing. Due to the risk of urinary retention (not being able to empty the bladder), only patients who are willing and able to initiate catheterization post treatment, if required, should be considered for treatment.

Patientstreatedforoveractivebladder:In clinical trials, 36 of the 552 patients had to self-catheterize for urinary retention following treatment with BOTOX compared to 2 of the 542 treated with placebo. The median duration of postinjection catheterization for these patients treated with BOTOX 100 Units (n = 36) was 63 days (minimum 1 day to maximum 214 days) as compared to a median duration of 11 days (minimum 3 days to maximum 18 days) for patients receiving placebo (n = 2). Patients with diabetes mellitus treated with BOTOX were more likely to develop urinary retention than nondiabetics.

Patientstreatedfor overactivebladder duetoneurologic disease:In clinical trials, 30.6% of patients (33/108) who were not using clean intermittent catheterization (CIC) prior to injection, required catheterization for urinary retention following treatment with BOTOX 200 Units as compared to 6.7% of patients (7/104) treated with placebo. The median duration of post-injection catheterization for these patients treated with BOTOX 200 Units (n = 33) was 289 days (minimum 1 day to maximum 530 days) as compared to a median duration of 358 days (minimum 2 days to maximum 379 days) for patients receiving placebo (n = 7). Among patients not using CIC at baseline, those with MS were more likely to require CIC post injection than those with SCI.

Thedoseof BOTOXisnot thesameas,orcomparableto, another botulinumtoxin product.

Seriousand/or immediate allergicreactionshavebeen reportedincluding itching, rash, red itchy welts, wheezing, asthma symptoms, or dizziness or feeling faint. Get medical help right away if you experience symptoms; further injection of BOTOX should be discontinued.

Tellyour doctor aboutallyour muscleornerveconditionssuch as ALS or Lou Gehrig's disease, myasthenia gravis, or Lambert-Eaton syndrome, as you may be at increased risk of serious side effects including difficulty swallowing and difficulty breathing from typical doses of BOTOX.

Tellyour doctor ifyou haveany breathing-related problems.Your doctor may monitor you for breathing problems during your treatment with BOTOX for spasticity or for detrusor overactivity associated with a neurologic condition. The risk of developing lung disease in patients with reduced lung function is increased in patients receiving BOTOX.

Corneaproblemshavebeen reported.Cornea (surface of the eye) problems have been reported in some people receiving BOTOX for their blepharospasm, especially in people with certain nerve disorders. BOTOX may cause the eyelids to blink less, which could lead to the surface of the eye being exposed to air more than is usual. Tell your doctor if you experience any problems with your eyes while receiving BOTOX. Your doctor may treat your eyes with drops, ointments, contact lenses, or with an eye patch.

Bleeding behind theeyehasbeen reported.Bleeding behind the eyeball has been reported in some people receiving BOTOX for their strabismus. Tell your doctor if you notice any new visual problems while receiving BOTOX.

Bronchitisand upperrespiratorytract infections (common colds) have been reported. Bronchitis was reported more frequently in adults receiving BOTOX for upper limb spasticity. Upper respiratory infections were also reported more frequently in adults with prior breathing related problems with spasticity. In pediatric patients treated with BOTOX for upper limb spasticity, upper respiratory tract infections were reported more frequently. In pediatric patients treated with BOTOX for lower limb spasticity, upper respiratory tract infections were not reported more frequently than placebo.

Autonomicdysreflexiain patientstreated for overactivebladder dueto neurologic disease. Autonomic dysreflexia associated with intradetrusor injections of BOTOX could occur in patients treated for detrusor overactivity associated with a neurologic condition and may require prompt medical therapy. In clinical trials, the incidence of autonomic dysreflexia was greater in patients treated with BOTOX 200 Units compared with placebo (1.5% versus 0.4%, respectively).

Tellyour doctor aboutallyour medicalconditions,includingifyou:have or have had bleeding problems; have plans to have surgery; had surgery on your face; weakness of forehead muscles; trouble raising your eyebrows; drooping eyelids; any other abnormal facial change; have symptoms of a urinary tract infection (UTI) and are being treated for urinary incontinence (symptoms of a urinary tract infection may include pain or burning with urination, frequent urination, or fever); have problems emptying your bladder on your own and are being treated for urinary incontinence; are pregnant or plan to become pregnant (it is not known if BOTOX can harm your unborn baby); are breastfeeding or plan to (it is not known if BOTOX passes into breast milk).

Tellyour doctor aboutallthemedicinesyou take,includingprescriptionand over-the-counter medicines,vitamins,andherbal supplements.UsingBOTOXwith certainother medicines may cause serious side effects. Do not start anynew medicinesuntil you havetoldyour doctor thatyouhavereceived BOTOXin the past.

Tell your doctor if you received any other botulinum toxin product in the last 4 months; have received injections of botulinum toxin such as Myobloc,Dysport, or Xeominin the past (tell your doctor exactly which product you received); have recently received an antibiotic by injection; take muscle relaxants; take an allergy or cold medicine; take a sleep medicine; take aspirin-like products or blood thinners.

Other sideeffects ofBOTOXinclude: dry mouth, discomfort or pain at the injection site, tiredness, headache, neck pain, eye problems: double vision, blurred vision, decreased eyesight, drooping eyelids, swelling of your eyelids, dry eyes; drooping eyebrows; and upper respiratory tract infection. In people being treated for urinary incontinence other side effects include: urinary tract infection, painful urination, and/or inability to empty your bladder on your own. If you have difficulty fully emptying your bladder after receiving BOTOX, you may need to use disposable self-catheters to empty your bladder up to a few times each day until your bladder is able to start emptying again.

For moreinformationrefer totheMedicationGuideor talk withyour doctor.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit http://www.fda.gov/medwatchor call 1-800-FDA-1088.

Please see BOTOX full Product Information including Boxed Warning and Medication Guide.

About AbbVie

AbbVie's mission is to discover and deliver innovative medicines that solve serious health issues today and address the medical challenges of tomorrow. We strive to have a remarkable impact on people's lives across several key therapeutic areas: immunology, oncology, neuroscience, eye care, virology, women's health and gastroenterology, in addition to products and services across its Allergan Aesthetics portfolio. For more information about AbbVie, please visit us at http://www.abbvie.com. Follow @abbvie on Twitter, Facebook, Instagram, YouTubeand LinkedIn.

Forward-Looking Statements

Some statements in this news release are, or may be considered, forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995. The words "believe," "expect," "anticipate," "project" and similar expressions, among others, generally identify forward-looking statements. AbbVie cautions that these forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially from those indicated in the forward-looking statements. Such risks and uncertainties include, but are not limited to, competition from other products, challenges to intellectual property, difficulties inherent in the research and development process, adverse litigation or government action, and changes to laws and regulations applicable to our industry. Additional information about the economic, competitive, governmental, technological and other factors that may affect AbbVie's operations is set forth in Item 1A, "Risk Factors," of AbbVie's 2019 Annual Report on Form 10-K, which has been filed with the Securities and Exchange Commission.AbbVie undertakes no obligation to release publicly any revisions to forward-looking statements as a result of subsequent events or developments, except as required by law.

References:

SOURCE AbbVie

abbvie.com

Go here to see the original:
FDA Approves Expanded BOTOX (onabotulinumtoxinA) Label for the Treatment of Pediatric Patients with Spasticity - PRNewswire

TRI-CITIES, WA - As students continue learning from home and using technology, increased screen time can have a negative impact on eyesight.

Madeline Carter talked with Dr. Elizabeth Heaston Thompson from the Heaston Thompson Vision Clinic to find out what parents can do to protect kids from vision problems related to online learning.

Dr. Liz says there are several things parents can do right now to protect their kids. She recommends:

Skipping lines of text when reading or re-reading lines

Headaches

Poor reading comprehension

Rubbing eyes

Short attention span with reading

Covering one eye when looking at something up close or in the distance

If local optometrists are not currently open for regular vision screenings, Dr. Liz suggests scheduling eye exams for the near future.

Read the original post:
Protecting kids from vision problems related to online learning - NBC Right Now

Specsavers has announced it is now taking appointments for customers who have experienced changes to their vision since their last eye test.

From 1 June, customers have been able to book in-store appointments, welcome news as research revealed a third of people in the UK have noticed a deterioration in their eyesight during lockdown.

Customers booking an appointment online will be contacted by their local store by phone to discuss their sight concerns, and to make sure that coming in to store is the best option.

The chain is currently unable to see customers who have not experienced changes to their vision.

The announcement of Specsavers taking appointments applies to England only; for the rest of the UK, appointments are for urgent and essential care only.

Here's everything you need to know:

Will social distancing be in place?

While lockdown measures may be easing slowly, it's still incredibly important that social distancing is adhered to.

As such, Specsavers is introducing a number of changes to the way it works in an effort to make sure its always as safe as possible for colleagues and customers.

The number of people in store will be limited, with one member of a household permitted inside at a time - unless they're with a child or vulnerable adult.

You'll also be asked to keep at least two metres from other customers.

Store teams will be wearing personal protective equipment (PPE) for their protection as well as yours.

Youll be welcome to try on as many glasses as youd like, but when you're finished you'll be asked to give them back to staff so they can be cleaned thoroughly.

Test rooms will also be thoroughly disinfected following consultations, as well as all testing equipment used during the eye test, ready for the next appointment.

Specsavers is also avoiding the use of cash, and any new pairs of glasses you buy can be delivered to your home, eliminating the need to come back to the store.

What if I can't make it to a store?

If you're unable to make it to a store, there are still ways in which Specsavers can help.

The chain's new RemoteCare service allows you to speak to an expert by video or over the phone about any sight or hearing questions you have.

Its free to use and you dont need to be a Specsavers customer to use it.

Contact lens top-ups, hearing aid batteries and even new specs can also be bought online.

Specsavers say: "If youve got an appointment booked, but youre not feeling well or you have any COVID-19 symptoms, wed ask that you dont come in until youre feeling better.

"Well make sure to arrange for a later date."

Originally posted here:
Essential eye tests open up in England to deal with lockdown sight deterioration - here's how to book - Lancashire Post

One of the main causes of the condition is atherosclerosis, a disease in which fatty deposits known as plaques build up on the interior of the artery walls. These plaques can rupture and send debris into the bloodstream, which can potentially cause a full or partial blockage in another vessel.

It makes sense, then, that the risk factors for atherosclerosis and for retinal vessel occlusion overlap. These include obesity, smoking, high cholesterol, high blood pressure and diabetes. Age is also a risk factor, with the majority of retinal vessel occlusions occurring in people who are 65 years of age and older. People living with a blood clotting disorder and those with glaucoma, which is chronically high pressure within the eye, are also at increased risk.

The same lifestyle changes that reduce the risk of atherosclerosis will also reduce the risk of retinal vessel occlusion, as well as diabetes, cardiovascular disease and stroke. A very important step is for smokers to quit. We know how difficult this is, so please ask your health care provider for help with crafting and sticking to a plan.

Limit alcohol consumption and get regular exercise. Eat a diet that is high in fresh vegetables, leafy greens, fruits and lean meats and low in added salt, sugar and unhealthy fats. You dont have to go for a halo here. We suggest our patients aim for 80% healthful eating. For those with health issues such as diabetes or hypertension, we tighten it up to 90% healthful eating.

More here:
ASK THE DOCTORS: Retinal artery occlusion related to atherosclerosis - Journal Times

The government has been urged to renew its guidance for supermarkets and address the pressing medical needs of people with eye conditions, as those living with sight loss warn they are being denied access to vital treatments and ignored as social distancing measures are implemented.

In a survey conducted by charity Fight for Sight, some four in 10 people said they feared their sight would further deteriorate during the pandemic, with some saying they had not been able to access regular injections and necessary surgeries to preserve their vision.

Meanwhile, 73 per cent of respondents to the poll of 325 adults with eye conditions said they had experienced reduced access to treatments during the outbreak. Two in five said they found it difficult to follow social distancing rules during the lockdown, with more than half saying they had seen their access to food and goods diminished during measures to stop the spread of the coronavirus.

Sharing the full story, not just the headlines

Angharad Paget-Jones, 27, who is registered blind and uses a guide dog, said she had been shouted at by members of the public after finding herself too close to them while out shopping while large supermarkets have not been able to make staff available to help her find the things she needs.

Meanwhile her guide dog, Tudor, is more likely to be confused than aided by yellow warning tape used to mark 2m distances which outside the context of the virus are often used to identify steps and trip hazards.

She told the Independent: Im told there are arrows and spacing on the floor, but as someone who cant see the ground and as somebody who cannot see the floor thats not very much good and my dog isnt trained [for this] ... hes not trained to know what they are. Its like the queueing outside supermarkets hes trained to find the door hes not trained to find the end of the queue.

She added that government messaging throughout the pandemic has frequently forgotten the needs of disabled people. They arent even putting audio descriptions on their feeds, theyre not putting out large print for us, they didnt even have sign language on the broadcasts so theyve forgotten disabled people and thats not good enough especially as everyone is one slip away from being disabled.

Meanwhile Elaine Young, 68, from South Lanarkshire in Scotland has had her local hospital cancel an appointment to treat her age-related macular degeneration and fears her eyesight may suffer as a consequence.

Im worried that by not having my injection, my eyesight is getting worse, she said. Ive noticed that there are more wavy lines in my vision.

Its frustrating because I have no idea when my next appointment will be or even when theyll start up the clinic again.

No hype, just the advice and analysis you need

The concern from disabled people comes a month after a cross-party letter signed by 97 MPs and peers urged the government to re-evaluate its current strategy to ensure social distancing does not lead to exclusion for those with disabilities.

Chief Executive of Fight for Sight, Sherine Krause said: The government must develop a plan that addresses the immediate need of people with eye conditions, so they dont become blind because of lockdown and social distancing measures.

Additionally, were calling on the government to urgently update its advice to retailers on social distancing measures to ensure the needs of people with poor vision are not excluded. In the longer term, we must continue to fund research for new, more efficient treatments and cures for the leading causes of blindness and sight loss, to help ease the pressure on our NHS.

Follow this link:
Theyve forgotten disabled people: Government urged to protect those with sight loss during outbreak - The Independent

It is feared that children spend too much time in front of the screen Image Credit: Supplied. For illustrative purpose only

Dubai: Over-exposure to screen time in recent weeks has resulted in a significant rise in complaints of eye issues such as redness and tired eyes, especially among children and young adults, claim eye specialists.

As per the World Economic Forum, globally around 1.2 billion children are out of classrooms, raising concerns over constant exposure to devices and their impact on eye health. Across the UAE, nearly 1.1 million students have been studying from home since March 2020.

According to Dr Mohit Jain, Specialist Ophthalmologist at RAK Hospital, students may be suffering from Computer Vision Syndrome and there is a need to minimise damage to the eyes.

Dr Jain said: Using digital devices has become unavoidable. However, when we focus on a screen, the muscles in the eyes contract. If the muscles stay contracted for too long, they get tired and lead to strain and may affect eyesight, especially in the growing age. This excessive use of devices not only puts a strain on the eyes but is also a risk factor for eye weakness and myopia. In other words, students staring at screens for prolonged periods may end up wearing glasses, and if they are wearing glasses already, the power may increase rapidly, warned Dr Jain.

More severe consequences of prolonged screen-time can be blurred vision, neck pain, irritated eyes, dizziness, double vision and difficulty in refocusing eyes.

Blink more often

Discussing tips on ways to moderate the excessive use of devices, Dr Jain advised that parents as a first step need to restrict the use of devices when it comes to entertainment and amusement. More importantly, children need to follow the 20-20-20 rule to give their eyes a much-needed break from watching the screen that is, after every 20 minutes of screen time; they should look away and stare at a distance of approximately 20 feet for 20 seconds before looking back at the device. This helps to relax the eye muscles, he said.

Dr Jain said the visual impact of screen learning prompt children to stare at screens for longer periods. Children tend to blink far less than they would usually do causing the eyes to dry out. Blinking keeps the eyes moist and clean. Therefore, parents should encourage their children to blink at regular intervals, even if it requires constant repeated reminders. A simple tip to do that is to stick a reminder note to the device itself, added Dr Jain. He also advised parents to ensure that children and young adults should keep their devices at a safe distance of 18 to 26 inches to avoid over-contracting the eye muscles.

Tips for eye protection

Make sure there is ample natural light in yur childs room when he or she is in a digital class.

Students need to follow the 20-20-20 rule ie take a break from the computer every 20 minutes and stay at a distance of 20 feet for 20 seconds to relax the eye muscle

Ask your child to blink more often when working on the computer

If there is redness, rashness , take care to provide medical attention

Go for eye check-ups regularly and get your childs vision assessed regularly so that he does not strain the eyes when he needs to correct his vision or when he needs an updraged number

Continued here:
Over-exposure to screen time leading to eye complaints among kids in the UAE - Gulf News

If you ever suddenly lose sight in one or both eyes, seek help immediately.

Q: A friend of our family suddenly lost the vision in his left eye because of something called retinal artery occlusion. What is that? How do you protect against it?

A: To answer your question, we should begin with a bit of anatomy. The retina is a layer of light-sensitive tissue that lines the back of the eye. Its job is to receive the incoming rays of light that pass through the lens and translate them into signals. These signals, or impulses, then travel along the optic nerve to the brain, which interprets them as the images we see. As with all tissues within the body, the retina needs a steady supply of blood to function properly. In the case of the retina, this comes primarily from an artery and a vein. If either of these vessels, or any of their smaller branches, become blocked, which is known as an occlusion, the retina sustains damage.

When a blockage occurs in the vein that serves the retina, the blood can't drain away. Instead, it backs up and raises pressure within the eye, which can cause serious damage that affects sight. When the blockage occurs in the artery, as with your family friend, the retina is starved of oxygen and nutrients. Unless blood flow is restored quickly, the blockage will cause the cells of the retina to die. The result is a loss of vision. Unfortunately, there is no way to reverse the damage that arises as a result of retinal vessel occlusion.

One of the main causes of the condition is atherosclerosis, a disease in which fatty deposits known as plaques build up on the interior of the artery walls. These plaques can rupture and send debris into the bloodstream, which can potentially cause a full or partial blockage in another vessel. It makes sense, then, that the risk factors for atherosclerosis and for retinal vessel occlusion overlap. These include obesity, smoking, high cholesterol, high blood pressure and diabetes. Age is also a risk factor, with the majority of retinal vessel occlusions occurring in people who are 65 and older. People living with a blood clotting disorder and those with glaucoma, which is chronically high pressure within the eye, are also at increased risk.

The same lifestyle changes that reduce the risk of atherosclerosis will also reduce the risk of retinal vessel occlusion, as well as diabetes, cardiovascular disease and stroke. A very important step is for smokers to quit. We know how difficult this is, so please ask your health care provider for help with crafting and sticking to a plan. Limit alcohol consumption and get regular exercise. Eat a diet that is high in fresh vegetables, leafy greens, fruits and lean meats and low in added salt, sugar and unhealthy fats. You don't have to go for a halo here. We suggest our patients aim for 80% healthful eating. For those with health issues such as diabetes or hypertension, we tighten it up to 90% healthful eating.

Retinal vessel occlusion is a medical emergency. If you ever suddenly lose sight in one or both eyes, seek help immediately.

Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024.

See the original post:
Retinal artery blockage can lead to lost vision: Ask the Doctors - GoErie.com

DEAR DOCTOR: A friend of our family suddenly lost the vision in his left eye because of something called retinal artery occlusion. What is that? How do you protect against it?

DEAR READER: To answer your question, we should begin with a bit of anatomy. The retina is a layer of light-sensitive tissue that lines the back of the eye. Its job is to receive the incoming rays of light that pass through the lens and translate them into signals. These signals, or impulses, then travel along the optic nerve to the brain, which interprets them as the images we see. As with all tissues within the body, the retina needs a steady supply of blood to function properly. In the case of the retina, this comes primarily from an artery and a vein. If either of these vessels, or any of their smaller branches, become blocked, which is known as an occlusion, the retina sustains damage.

When a blockage occurs in the vein that serves the retina, the blood cant drain away. Instead, it backs up and raises pressure within the eye, which can cause serious damage that affects sight. When the blockage occurs in the artery, as with your family friend, the retina is starved of oxygen and nutrients. Unless blood flow is restored quickly, the blockage will cause the cells of the retina to die. The result is a loss of vision. Unfortunately, there is no way to reverse the damage that arises as a result of retinal vessel occlusion.

One of the main causes of the condition is atherosclerosis, a disease in which fatty deposits known as plaques build up on the interior of the artery walls. These plaques can rupture and send debris into the bloodstream, which can potentially cause a full or partial blockage in another vessel. It makes sense, then, that the risk factors for atherosclerosis and for retinal vessel occlusion overlap. These include obesity, smoking, high cholesterol, high blood pressure and diabetes. Age is also a risk factor, with the majority of retinal vessel occlusions occurring in people who are 65 years of age and older. People living with a blood clotting disorder and those with glaucoma, which is chronically high pressure within the eye, are also at increased risk.

The same lifestyle changes that reduce the risk of atherosclerosis will also reduce the risk of retinal vessel occlusion, as well as diabetes, cardiovascular disease and stroke. A very important step is for smokers to quit. We know how difficult this is, so please ask your health care provider for help with crafting and sticking to a plan. Limit alcohol consumption and get regular exercise. Eat a diet that is high in fresh vegetables, leafy greens, fruits and lean meats and low in added salt, sugar and unhealthy fats. You dont have to go for a halo here. We suggest our patients aim for 80% healthful eating. For those with health issues such as diabetes or hypertension, we tighten it up to 90% healthful eating.

Retinal vessel occlusion is a medical emergency. If you ever suddenly lose sight in one or both eyes, seek help immediately.

Eve Glazier, M.D., MBA, is an internist and associate professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10880 Wilshire Blvd., Suite 1450, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.

We are making critical coverage of the coronavirus available for free. Please consider subscribing so we can continue to bring you the latest news and information on this developing story.

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Eye problem related to atherosclerosis | Community | times-news.com - Cumberland Times-News

BRITISH Prime Minister Boris Johnson's chief adviser Dominic Cummings last week claimed he had travelled with his family to Barnard Castle in County Durham "to see if I could drive safely". His explanation was that he had thought his vision might have been affected by coronavirus.

Eye symptoms are recognised as a possible symptom of the disease conjunctivitis, sticky eyes and red eyes have been reported in around a third of patients according to a small study in Wuhan, China, published in March.

Conjunctivitis is also included as a less common symptom in the World Health Organisation's official list. But could Covid-19 affect vision? Robert MacLaren, a professor of ophthalmology at Oxford University, says: "You would be expected to make a full recovery from the eye problems reported so far, although it may cause temporary difficulties such as blurred vision."

The Royal National Institute Of Blind People says: "There is no evidence of sight loss caused directly by the virus," but noted "research is being carried out into some very rare cases that appear to be secondary to other complications such as blood clots caused by the virus".

Solo dmg media

Link:
Can the coronavirus really affect sufferers' eyes, as Dominic Cummings claimed? - The Irish News

Dear Doctor: A friend of our family suddenly lost the vision in his left eye because of something called retinal artery occlusion. What is that? How do you protect against it?

Dear Reader: To answer your question, we should begin with a bit of anatomy. The retina is a layer of light-sensitive tissue that lines the back of the eye. Its job is to receive the incoming rays of light that pass through the lens and translate them into signals. These signals, or impulses, then travel along the optic nerve to the brain, which interprets them as the images we see. As with all tissues within the body, the retina needs a steady supply of blood to function properly. In the case of the retina, this comes primarily from an artery and a vein. If either of these vessels, or any of their smaller branches, become blocked, which is known as an occlusion, the retina sustains damage.

When a blockage occurs in the vein that serves the retina, the blood can't drain away. Instead, it backs up and raises pressure within the eye, which can cause serious damage that affects sight. When the blockage occurs in the artery, as with your family friend, the retina is starved of oxygen and nutrients. Unless blood flow is restored quickly, the blockage will cause the cells of the retina to die. The result is a loss of vision. Unfortunately, there is no way to reverse the damage that arises as a result of retinal vessel occlusion.

Originally posted here:
Retinal artery occlusion related to atherosclerosis | | thetandd.com - The Times and Democrat

A GRANDDAD has had his sight saved thanks to opticians and surgeons.

Robert Scott, from Paddington, woke up one morning last month with a shadow on the bottom of his right eye.

At the urging of his wife Anne, the 63-year-old made an appointment at Specsavers on Sankey Street in the town centre where he was examined by optometrist Andrea Eaton.

She said: "I spoke to Robert initially on the phone to assess the situation and invited him into the store for a thorough examination later that day.

"Although closed for routine appointments, we have remained open for those requiring immediate attention while following government advice on social distancing and hygiene.

"It was clear upon close inspection that Roberts retina had detached from its position, becoming separated from the blood supply that provides it with essential nutrients and oxygen.

"I referred him immediately to the St Pauls Eye Unit at the Royal Liverpool University Hospital."

Retired company director Robert underwent surgery to reattach the retina the next day in order to save his sight.

The dad-of-two and granddad-of-four is now recovering at home after a successful operation.

He said: "When the shadow in my vision first appeared, I went to bed and thought nothing of it.

"It was only when I mentioned it to my wife the next day that I was compelled to get it looked at.

I had no idea it could be so serious.

"Id encourage anyone else experiencing unusual symptoms to get checked out straight away.

"Thanks to Andreas quick action in-store at Specsavers and the talented surgeons that worked on me, my sight will eventually return.

"For that Im very grateful."

Continue reading here:
Granddad has sight saved by opticians at Specsavers - Warrington Guardian

Ive been watching a lot of NASCAR lately, primarily because its the only sport that has gotten everything up and running again with any sort of regularity. That isnt to say things are back to normal, because with no fans and everyone at the track wearing masks, its clear we still have a while to go.

However, during a recent race, something unusual and completely unrelated to safety measures caught my eye (a pun, as youll soon see, could not have been more intended).

While looking at Joey Loganos in-car camera, I noticed he was wearing what appeared to be a pair of run-of-the-mill prescription glasses beneath his helmet. This stuck with me for two reasons because A) I would have thought driving a racecar would be more of a contact lens situation and B) it was an inspiring example of an athlete with less-than-great eyesight making it work.

I grew up with lousy eyes. If I had a pair of billiard balls in my eye sockets, my vision would only be marginally worse than it is now. At a certain point, I was forced to don a pair of glasses and endure the common barrage of childhood taunts that come with them, like four eyes and Look at this guy with his glasses! What do you do? Read books or something? Ha!

Fortunately for me and other people with vision issues, there have been heroic athletes who broke barriers by wearing glasses where no glasses had been worn before (or where its at least fairly inconvenient).

Lets take a look at some of the sports worlds bespectacled heroes.

When I was playing Little League and swinging at every ball that came my way (and several other flying objects I thought were baseballs but turned out not to be), I thought my hopes of making it to The Show were dashed. Damn you, feeble eyes. Damn you!

However, proof that poor eyesight was not a baseball career death sentence would come by way of the Great White North. Enter: Eric Gagne.

Best remembered as a closer for the Los Angeles Dodgers (where he was an absolute save machine), Gagne also brought some serious specs to the mound. They looked like theyd be at home at the shooting range just as much as they did on the mound.

Imagine having to come to the plate in the ninth down by two. The entire game rests on your shoulders. Youre shaking in your cleats as it is, and now, youre getting the stare down from those glasses. Youd swing at anything just to retreat into the clubhouse and drink a beer.

While pitching ability is probably the main reason Gagne was able to become the fastest pitcher to reach 100 saves, I like to think the glasses helped a little bit.

Folks, its important to remember that there are other eye maladies than just not seeing clearly. Thats why Kareem Abdul-Jabbar, the NBAs all-time leading scorer, opted to throw on his iconic goggles in the first place. Due in part to his height, Kareem got poked in the eyes a lot, and back in his college days, he even missed two games with a cornea injury.

Everyone knows you cant rack up copious amounts of points if youre sitting on the bench or missing an eye thanks to a defenders rogue finger. Youve got to protect those peepers, and if that means goggles, you wear goggles.

Abdul-Jabbar was a member of the Milwaukee Bucks and the Los Angeles Lakers during his career, but yknow what? He was also a Trailblazer.for eye protection.

Even the gridiron has seen some glasses and (with apologies to Rodrigo Blankenship) there is perhaps no case more notable thanLos Angeles Rams running back Eric Dickerson.

Dickerson sported a pair of rec specs during his time in the league, even if it was a less than desirable necessity. In a 2016 interview on the NFL Network, Dickerson was asked if his trademark frames were prescription or all style, to which he responded:

I am blind as a bat. I hated them goggles. I hated wearing those goggles.

I tried to go without them a couple times. Id go through practice and put contacts in. They worked. Id get into the game. I said, Keep my goggles on the sideline. First hit, contacts pop out.

Whether he was a fan of his eyewear or not, they helped Dickerson become a Pro Football Hall of Famer, and if there was an Athletic Eyewear Hall of Fame (which Im now realizing should be in Los Angles because that seems to be where everyone with glasses played at some point) hed be a first-ballot inductee there too.

No, notthoseHanson Brothers. Were talking about another group of long-haired siblings who played together 20 years before MMMBop dominated the charts: Jack, Steve, and Jeff Hanson, who were scoffed at for their numerous eccentricities from the moment they arrived in Charleston, West Virginia in Slap Shot.

They were mocked for beating up a soda machine that had the audacity to take their quarter, playing slot cars in their hotel room on a road trip, and, of course, for all wearing thick-rimmed, Buddy Holly-esque glasses.

But the second the three got the nod from Chiefs player-coach Reggie Dunlop in a game against the Broome County Blades, the trio took the entire Federal League by storm, dismantling the opposition and even squaring up against the likes of Tim Dr. Hook McCracken and the fearsome Ogie Oglethorpe.

The Hansons are some of the greatest inspirations in the history of corrective athletic optometry. It could be even be argued by some that their presence helped to keep the Chiefs from relocating to Florida.

The Hanson Brothers: absolute legends of both the rink and the optometrists office.

Read more here:
Lets Appreciate The Athletes Who Managed To Make Rec Specs Look Cooler Than They Have Any Right To Be - BroBible

If you have aneye examand are told you have 20/20 vision, does this mean you have perfect eyesight? Is it possible to achieve even better than 20/20 vision? And what is "perfect vision" anyway?

To answer these questions, let's take a closer look at vision-related terminology to fully understand howeye doctorsmeasure the quality of your vision.

Visual acuity.This, literally, is the sharpness of your vision. Visual acuity is measured by your ability to identify letters or numbers on a standardizedeye chartfrom a specific viewing distance.

Visual acuity is a static measurement, meaning you are sitting still during the testing and the letters or numbers you are viewing also are stationary.

Visual acuity also is tested under high contrast conditions typically, the letters or numbers on the eye chart are black, and the background of the chart is white.

Although visual acuity testing is very useful to determine the relative clarity of your eyesight in standardized conditions, it isn't predictive of the quality of your vision in all situations. For example, it can't predict how well you would see:

Three major physical and neurological factors determine visual acuity:

How accurately thecorneaand lens of the eye focus light onto theretina

The sensitivity of the nerves in the retina and vision centers in the brain

The ability of the brain to interpret information received from the eyes

Only light that is focused on a very small and highly sensitive portion of the central retina (called themacula) influences visual acuity measurements obtained during an eye exam.

Visual acuity typically is quantified with Snellen fractions (see "What is 20/20 Vision?" below).

Eyesight.The exact definition of "eyesight" is difficult to pin down. Depending on which dictionary or other resource you check, it can mean "ability to see," "the sense of seeing," "vision," "range of sight" or "view." Often, the terms "eyesight" and "visual acuity" are used interchangeably.

Vision.This is a broader term than visual acuity or eyesight. In addition to sharpness of sight or simply a description of the ability to see, the term "vision" usually includes a wider range of visual abilities and skills. These includecontrast sensitivity, the ability to track moving objects with smooth and accurate eye movements,color vision, depth perception, focusing speed and accuracy, and more.

If this more inclusive (and accurate) definition of "vision" is used, what most people call "20/20 vision" should really be called "20/20 visual acuity." Realistically, that probably won't happen. For better or worse, the term "20/20 vision" is likely here to stay.

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The term "20/20" and similar fractions (such as 20/40, 20/60, etc.) are visual acuity measurements. They also are called Snellen fractions, named after Herman Snellen, the Dutch ophthalmologist who developed this measurement system in 1862.

In the Snellen visual acuity system, the top number of the Snellen fraction is the viewing distance between the patient and the eye chart. In the United States, this distance typically is 20 feet; in other countries, it is 6 meters.

At this testing distance, the size of the letters on one of the smaller lines near the bottom of the eye chart has been standardized to correspond to "normal" visual acuity this is the "20/20" line. If you can identify the letters on this line but none smaller, you have normal (20/20) visual acuity.

The increasingly larger letter sizes on the lines on the Snellen chart above the 20/20 line correspond to worse visual acuity measurements (20/40, 20/60, etc.); the lines with smaller letters below the 20/20 line on the chart correspond to visual acuity measurements that are even better than 20/20 vision (e.g., 20/15, 20/12, 20/10).

The single big "E" at the top of most Snellen eye charts corresponds to 20/200 visual acuity. If this is the smallest letter size you can discern with your best corrective lenses in front of your eyes, you arelegally blind.

On most Snellen charts, the smallest letters correspond to 20/10 visual acuity. If you have 20/10 visual acuity, your eyesight is twice as sharp as that of a person with normal (20/20) vision.

Yes, it's indeed possible to have sharper than 20/20 vision. In fact, most people with young, healthy eyes are capable of identifying at least some of the letters on the 20/15 line or even smaller letters on the Snellen chart.

This may be due in part to better printing methods available today vs. those in the 19th century when Snellen was determining the smallest letters a person with normal vision should be able to discern. So a case could be made that "normal" visual acuity today is an ability to identify letters that are a bit smaller than those on the 20/20 line of a traditional Snellen eye chart.

On the other hand, people are living longer today than they did in Snellen's era. Normal aging changes in the eye, such as earlycataracts, could justify considering somewhat larger letters than those on the 20/20 line as being indicative of "normal" vision among adults in their 60s or older.

Regardless of these considerations, let's say your eye doctor says you have 20/20 vision (or, more accurately, 20/20 visual acuity), and you want sharper eyesight. What can you do?

If your 20/20 vision doesn't seem sharp enough, it could be that your eyes havehigher-order aberrations (HOAs)that cannot be corrected with regular eyeglasses or soft contact lenses. Your eye doctor can check for these aberrations withwavefront technologythat is available in some eye care practices.

If HOAs are caused by small irregularities in the shape of the front surface of your eyes, being fitted withgas permeable contact lenses (GP lenses)often can improve your visual acuity better than eyeglasses or soft contact lenses. This is because GP lenses are rigid and essentially replace the eye's irregular front surface with a perfectly smooth, curved surface to focus light more accurately.

Another option might becustom wavefront LASIK. This personalized laser vision correction surgery can provide vision that is comparable to wearing rigid gas permeable contact lenses (which often is sharper than the visual acuity provided by glasses or soft contact lenses), without the hassle of the daily contact lens care.

If you prefer to wear eyeglasses to correct your refractive errors, glasses with specialhigh-definition lenses might give you sharper vision than regular eyeglass lenses.

It's nearly impossible to quantify what "perfect" vision is. A more interesting question is, "Perfect for what?"

For example, if you are driving on a sunny day, excellent Snellen visual acuity might be the main factor in your satisfaction with your vision. But your traveling companion, who has worse visual acuity than yours, might be happier with her vision in the same circumstances because she is wearing polarized sunglasses with anti-reflective coating that enhance contrast and block glare.

Or an athlete who has better than 20/20 vision might struggle with his performance because he doesn't have certain dynamic visual skills that allow him to react to moving objects as quickly as a teammate whose static visual acuity isn't as sharp as his.

The first step to maximizing the clarity and comfort of your eyesight in all situations is to see a qualified optometrist orophthalmologistfor a comprehensive eye exam and vision evaluation.

If you are interested in finding out if laser vision correction could sharpen your vision better than glasses or contacts, ask to be referred to an experiencedLASIK surgeonfor a consultation.

If you want to maximize your dynamic vision skills for sports and other activities, seek an eye doctor who is a sports vision specialist and ask aboutsports vision training.

Finally, if your child has 20/20 vision but is struggling with eye strain and other vision problems in school, seek the advice of an eye care provider who specializes in children's vision to have your child evaluated for possiblelearning-related vision problems.

Ready to have your eyes checked? Find an eye doctor near you.

Page updated April 2019

Read more:
Visual Acuity: Is 20/20 Perfect Vision?

1. Flashing Lights, Floaters, or a Gray Shadow in Your Vision

The sudden onset of flashing lights, a noticeable increase in the amount of floaters, a shadow in your peripheral vision, or a gray curtain moving across your field of vision could be signs of a detachment of the retina the nerve layer in the back of the eye that sends images to the brain. Nearsightedness, eye diseases like glaucoma, and physical injury to the eye are among the causes of retinal detachment. Unless treated quickly, usually with surgery, retinal detachment can lead to blindness.

Sudden vision loss could signal a number of eye diseases and conditions. One is macular degeneration, also known as age-related macular degeneration or AMD, which is a leading cause of vision loss in people 65 and older in the United States. Vision loss caused by AMD can be gradual, but in some cases it can be sudden when blood vessels in the eye leak fluid or blood under the retina, which is made up of nerve cells that allow you to see.

Another cause of sudden vision loss could be a type of glaucoma, which leads to a rapid buildup of fluid pressure in the eye that damages the optic nerve. There are many other conditions that can cause persistentloss of vision.

Most eye diseases are painless, but some conditions or injuries can result in eye pain, says Richard Shugarman, MD, an ophthalmologist in West Palm Beach, Florida. Eye pain can be caused by glaucoma,dry eye, an eye injury, a scratched cornea, or even cancer of the eye.

Any significantinjury to the eyeshould be evaluated by a doctor, particularly if there is redness or pain that lasts for more than 15 to 20 minutes.

If you experience any discomfort in your eye after doing an activity in which a small particle could have entered your eye, such as hammering or working under a car, dont ignore it. Have your eyes checked out by a doctor to make sure that you dont have a foreign particle in the eye, which can cause an infection.

Having two red eyes is probably not as serious as one red eye, says Dr. Shurgarman. When both eyes are red at the same time, it could be a sign of a cold orconjunctivitis (pink eye) minor infections that are self-healing. But one red eye can be an indicator of a deeper inflammation, such as scleritis or uveitis. Scleritis is the inflammation of the tough, outer protective barrier around the eye, and uveitis is the inflammation and swelling of the middle coating of the eyeball.

While most people who use contact lenses dont experience problems when they follow the rules of proper contact lens care and use, serious infections can occasionally occur. If you wear contact lenses, never ignore eye pain, redness, or discomfort see an eye doctor right away.

Even if it clears up, blurred vision can be a sign of a number of eye problems, such as glaucoma, uveitis, a torn retina, or AMD. Losing vision in one eye may be an early symptom of astroke. Vision loss, especially in one eye, could be a sign that the carotid artery, which is a major supplier of blood to the eyes, is blocked, says Shugarman.

If youve had eye surgery and experience any redness, eye pain, or blurring of vision, call your doctor right away for an evaluation.

Even if a symptom appears to go away, youre better off checking with your eye specialist if you encounter any of these warning signs.

Here is the original post:
9 Serious Vision Symptoms to Watch Out For | Everyday Health

"6/6" redirects here. For the date, see June 6.

Visual acuity (VA) commonly refers to the clarity of vision, but technically rates an examinee's ability to recognize small details with precision. Visual acuity is dependent on optical and neural factors, i.e., (1) the sharpness of the retinal focus within the eye, (2) the health and functioning of the retina, and (3) the sensitivity of the interpretative faculty of the brain.[1]

A common cause of low visual acuity is refractive error (ametropia), errors in how the light is refracted in the eyeball, and errors in how light entering the eye is interpreted by the brain. The latter is the primary cause for low vision in people with albinism. . Causes of refractive errors include aberrations in the shape of the eyeball or the cornea, and reduced flexibility of the lens. Too high or too low refractive error (in relation to the length of the eyeball) is the cause of nearsightedness (myopia) or farsightedness (hyperopia) (normal refractive status is referred to as emmetropia). Other optical causes are astigmatism or more complex corneal irregularities. These anomalies can mostly be corrected by optical means (such as eyeglasses, contact lenses, laser surgery, etc.).

Neural factors that limit acuity are located in the retina or the brain (or the pathway leading there). Examples for the first are a detached retina and macular degeneration, to name just two. Another common impairment, amblyopia, is caused by the visual brain not having developed properly in early childhood. In some cases, low visual acuity is caused by brain damage, such as from traumatic brain injury or stroke. When optical factors are corrected for, acuity can be considered a measure of neural well-functioning.

Visual acuity is typically measured while fixating, i.e. as a measure of central (or foveal) vision, for the reason that it is highest there. However, acuity in peripheral vision can be of equal (or sometimes higher) importance in everyday life. Acuity declines towards the periphery in an inverse-linear fashion (i.e. the decline follows approximately a hyperbola).[2][3] The decline is according to E2/(E2+E), where E is eccentricity in degrees visual angle[verification needed], and E2 is a constant of approximately 2 deg[4][5][6]. At 2 deg eccentricity, for example, acuity is half the foveal value. The visual acuity standard does not recognize an examinee's ability to recognize large objects or symbols that are exceed the size and quality offered by a standard exam. Nor can visual acuity alone cannot determine the over all quality visual function.

Visual acuity is a measure of the spatial resolution of the visual processing system. VA, as it is sometimes referred to by optical professionals, is tested by requiring the person whose vision is being tested to identify so-called optotypes stylized letters, Landolt rings, pediatric symbols, symbols for the illiterate, standardized Cyrillic letters in the GolovinSivtsev table, or other patterns on a printed chart (or some other means) from a set viewing distance. Optotypes are represented as black symbols against a white background (i.e. at maximum contrast). The distance between the person's eyes and the testing chart is set so as to approximate "optical infinity" in the way the lens attempts to focus (far acuity), or at a defined reading distance (near acuity).

A reference value above which visual acuity is considered normal is called 6/6 vision, the USC equivalent of which is 20/20 vision: At 6 metres or 20 feet, a human eye with that performance is able to separate contours that are approximately 1.75 mm apart.[7] Vision of 6/12 corresponds to lower performance, while vision of 6/3 to better performance. Normal individuals have an acuity of 6/4 or better (depending on age and other factors).

In the expression 6/x vision, the numerator (6) is the distance in metres between the subject and the chart and the denominator (x) the distance at which a person with 6/6 acuity would discern the same optotype. Thus, 6/12 means that a person with 6/6 vision would discern the same optotype from 12 metres away (i.e. at twice the distance). This is equivalent to saying that with 6/12 vision, the person possesses half the spatial resolution and needs twice the size to discern the optotype.

A simple and efficient way to state acuity is by converting the fraction to a decimal: 6/6 then corresponds to an acuity (or a Visus) of 1.0 (see Expression below), while 6/3 corresponds to 2.0, which is often attained by well-corrected healthy young subjects with binocular vision. Stating acuity as a decimal number is the standard in European countries, as required by the European norm (EN ISO 8596, previously DIN 58220).

The precise distance at which acuity is measured is not important as long as it is sufficiently far away and the size of the optotype on the retina is the same. That size is specified as a visual angle, which is the angle, at the eye, under which the optotype appears. For 6/6 = 1.0 acuity, the size of a letter on the Snellen chart or Landolt C chart is a visual angle of 5 arc minutes (1 arc min = 1/60 of a degree). By the design of a typical optotype (like a Snellen E or a Landolt C), the critical gap that needs to be resolved is 1/5 this value, i.e., 1 arc min. The latter is the value used in the international definition of visual acuity:

Acuity is a measure of visual performance and does not relate to the eyeglass prescription required to correct vision. Instead, an eye exam seeks to find the prescription that will provide the best corrected visual performance achievable. The resulting acuity may be greater or less than 6/6 = 1.0. Indeed, a subject diagnosed as having 6/6 vision will often actually have higher visual acuity because, once this standard is attained, the subject is considered to have normal (in the sense of undisturbed) vision and smaller optotypes are not tested. Subjects with 6/6 vision or "better" (20/15, 20/10, etc.) may still benefit from an eyeglass correction for other problems related to the visual system, such as hyperopia, ocular injuries, or presbyopia.

Visual acuity is measured by a psychophysical procedure and as such relates the physical characteristics of a stimulus to a subject's percept and his/her resulting responses. Measurement can be by using an eye chart invented by Ferdinand Monoyer, by optical instruments, or by computerized tests[8] like the FrACT.[9]

Care must be taken that viewing conditions correspond to the standard,[10] such as correct illumination of the room and the eye chart, correct viewing distance, enough time for responding, error allowance, and so forth. In European countries, these conditions are standardized by the European norm (EN ISO 8596, previously DIN 58220).

Theodor Wertheim in Berlin presents detailed measurements of acuity in peripheral vision.[2][15]

Hugh Taylor uses these design principles for a "Tumbling E Chart" for illiterates, later used[16] to study the visual acuity of Australian Aborigines.[12]

Rick Ferris et al. of the National Eye Institute chooses the LogMAR chart layout, implemented with Sloan letters, to establish a standardized method of visual acuity measurement for the Early Treatment of Diabetic Retinopathy Study (ETDRS).These charts are used in all subsequent clinical studies, and did much to familiarize the profession with the new layout and progression. Data from the ETDRS were used to select letter combinations that give each line the same average difficulty, without using all letters on each line.

The International Council of Ophthalmology approves a new 'Visual Acuity Measurement Standard', also incorporating the above features.

Antonio Medina and Bradford Howland of the Massachusetts Institute of Technology develop a novel eye testing chart using letters that become invisible with decreasing acuity, rather than blurred as in standard charts. They demonstrate the arbitrary nature of the Snellen fraction and warn about the accuracy of visual acuity determined by using charts of different letter types, calibrated by Snellen's system.[17]

Daylight vision (i.e. photopic vision) is subserved by cone receptor cells which have high spatial density (in the central fovea) and allow high acuity of 6/6 or better. In low light (i.e., scotopic) vision, cones do not have sufficient sensitivity and vision is subserved by rods. Spatial resolution is then much lower. This is due to spatial summation of rods, i.e. a number of rods merge into a bipolar cell, in turn connecting to a ganglion cell, and the resulting unit for resolution is large, and acuity small. Note that there are no rods in the very center of the visual field (the foveola), and highest performance in low light is achieved in near peripheral vision[2]

The maximum angular resolution of the human eye is 28 arc seconds or 0.47 arc minutes,[18] this gives an angular resolution of 0.008 degrees, and at a distance of 1km corresponds to 136mm. This is equal to 0.94 arc minutes per line pair (one white and one black line), or 0.016 degrees. For a pixel pair (one white and one black pixel) this gives a pixel density of 128 pixels per degree (PPD).

6/6 vision is defined as the ability to resolve two points of light separated by a visual angle of one minute of arc, corresponding to 60 PPD, or about 290350 pixels per inch for a display on a device held 250 to 300mm from the eye.[19]

Thus, visual acuity, or resolving power (in daylight, central vision), is the property of cones.[20]To resolve detail, the eye's optical system has to project a focused image on the fovea, a region inside the macula having the highest density of cone photoreceptor cells (the only kind of photoreceptors existing in the fovea's very center of 300 m diameter), thus having the highest resolution and best color vision. Acuity and color vision, despite being mediated by the same cells, are different physiologic functions that do not interrelate except by position. Acuity and color vision can be affected independently.

The grain of a photographic mosaic has just as limited resolving power as the "grain" of the retinal mosaic. To see detail, two sets of receptors must be intervened by a middle set. The maximum resolution is that 30 seconds of arc, corresponding to the foveal cone diameter or the angle subtended at the nodal point of the eye. To get reception from each cone, as it would be if vision was on a mosaic basis, the "local sign" must be obtained from a single cone via a chain of one bipolar, ganglion, and lateral geniculate cell each. A key factor of obtaining detailed vision, however, is inhibition. This is mediated by neurons such as the amacrine and horizontal cells, which functionally render the spread or convergence of signals inactive. This tendency to one-to-one shuttle of signals is powered by brightening of the center and its surroundings, which triggers the inhibition leading to a one-to-one wiring. This scenario, however, is rare, as cones may connect to both midget and flat (diffuse) bipolars, and amacrine and horizontal cells can merge messages just as easily as inhibit them.[7]

Light travels from the fixation object to the fovea through an imaginary path called the visual axis. The eye's tissues and structures that are in the visual axis (and also the tissues adjacent to it) affect the quality of the image. These structures are: tear film, cornea, anterior chamber, pupil, lens, vitreous, and finally the retina. The posterior part of the retina, called the retinal pigment epithelium (RPE) is responsible for, among many other things, absorbing light that crosses the retina so it cannot bounce to other parts of the retina. In many vertebrates, such as cats, where high visual acuity is not a priority, there is a reflecting tapetum layer that gives the photoreceptors a "second chance" to absorb the light, thus improving the ability to see in the dark. This is what causes an animal's eyes to seemingly glow in the dark when a light is shone on them. The RPE also has a vital function of recycling the chemicals used by the rods and cones in photon detection. If the RPE is damaged and does not clean up this "shed" blindness can result.

As in a photographic lens, visual acuity is affected by the size of the pupil. Optical aberrations of the eye that decrease visual acuity are at a maximum when the pupil is largest (about 8mm), which occurs in low-light conditions. When the pupil is small (12mm), image sharpness may be limited by diffraction of light by the pupil (see diffraction limit). Between these extremes is the pupil diameter that is generally best for visual acuity in normal, healthy eyes; this tends to be around 3 or 4mm.

If the optics of the eye were otherwise perfect, theoretically, acuity would be limited by pupil diffraction, which would be a diffraction-limited acuity of 0.4 minutes of arc (minarc) or 6/2.6 acuity. The smallest cone cells in the fovea have sizes corresponding to 0.4 minarc of the visual field, which also places a lower limit on acuity. The optimal acuity of 0.4 minarc or 6/2.6 can be demonstrated using a laser interferometer that bypasses any defects in the eye's optics and projects a pattern of dark and light bands directly on the retina. Laser interferometers are now used routinely in patients with optical problems, such as cataracts, to assess the health of the retina before subjecting them to surgery.

The visual cortex is the part of the cerebral cortex in the posterior part of the brain responsible for processing visual stimuli, called the occipital lobe. The central 10 of field (approximately the extension of the macula) is represented by at least 60% of the visual cortex. Many of these neurons are believed to be involved directly in visual acuity processing.

Proper development of normal visual acuity depends on a human or an animal having normal visual input when it is very young. Any visual deprivation, that is, anything interfering with such input over a prolonged period of time, such as a cataract, severe eye turn or strabismus, anisometropia (unequal refractive error between the two eyes), or covering or patching the eye during medical treatment, will usually result in a severe and permanent decrease in visual acuity and pattern recognition in the affected eye if not treated early in life, a condition known as amblyopia. The decreased acuity is reflected in various abnormalities in cell properties in the visual cortex. These changes include a marked decrease in the number of cells connected to the affected eye as well as cells connected to both eyes in cortical area V1, resulting in a loss of stereopsis, i.e. depth perception by binocular vision (colloquially: "3D vision"). The period of time over which an animal is highly sensitive to such visual deprivation is referred to as the critical period.

The eye is connected to the visual cortex by the optic nerve coming out of the back of the eye. The two optic nerves come together behind the eyes at the optic chiasm, where about half of the fibers from each eye cross over to the opposite side and join fibers from the other eye representing the corresponding visual field, the combined nerve fibers from both eyes forming the optic tract. This ultimately forms the physiological basis of binocular vision. The tracts project to a relay station in the midbrain called the lateral geniculate nucleus, part of the thalamus, and then to the visual cortex along a collection of nerve fibers called the optic radiation.

Any pathological process in the visual system, even in older humans beyond the critical period, will often cause decreases in visual acuity. Thus measuring visual acuity is a simple test in accessing the health of the eyes, the visual brain, or pathway to the brain. Any relatively sudden decrease in visual acuity is always a cause for concern. Common causes of decreases in visual acuity are cataracts and scarred corneas, which affect the optical path, diseases that affect the retina, such as macular degeneration and diabetes, diseases affecting the optic pathway to the brain such as tumors and multiple sclerosis, and diseases affecting the visual cortex such as tumors and strokes.

Though the resolving power depends on the size and packing density of the photoreceptors, the neural system must interpret the receptors information. As determined from single-cell experiments on the cat and primate, different ganglion cells in the retina are tuned to different spatial frequencies, so some ganglion cells at each location have better acuity than others. Ultimately, however, it appears that the size of a patch of cortical tissue in visual area V1 that processes a given location in the visual field (a concept known as cortical magnification) is equally important in determining visual acuity. In particular, that size is largest in the fovea's center, and decreases with increasing distance from there.[2]

Besides the neural connections of the receptors, the optical system is an equally key player in retinal resolution. In the ideal eye, the image of a diffraction grating can subtend 0.5 micrometre on the retina. This is certainly not the case, however, and furthermore the pupil can cause diffraction of the light. Thus, black lines on a grating will be mixed with the intervening white lines to make a gray appearance. Defective optical issues (such as uncorrected myopia) can render it worse, but suitable lenses can help. Images (such as gratings) can be sharpened by lateral inhibition, i.e., more highly excited cells inhibiting the less excited cells. A similar reaction is in the case of chromatic aberrations, in which the color fringes around black-and-white objects are inhibited similarly.[7]

Visual acuity is often measured according to the size of letters viewed on a Snellen chart or the size of other symbols, such as Landolt Cs or the E Chart.

In some countries, acuity is expressed as a vulgar fraction, and in some as a decimal number.

Using the metre as a unit of measurement, (fractional) visual acuity is expressed relative to 6/6. Otherwise, using the foot, visual acuity is expressed relative to 20/20. For all practical purposes, 20/20 vision is equivalent to 6/6. In the decimal system, acuity is defined as the reciprocal value of the size of the gap (measured in arc minutes) of the smallest Landolt C, the orientation of which can be reliably identified. A value of 1.0 is equal to 6/6.

LogMAR is another commonly used scale, expressed as the (decadic) logarithm of the minimum angle of resolution (MAR). The LogMAR scale converts the geometric sequence of a traditional chart to a linear scale. It measures visual acuity loss: positive values indicate vision loss, while negative values denote normal or better visual acuity. This scale is commonly used clinically and in research because the lines are of equal length and so it forms a continuous scale with equally spaced intervals between points, unlike snellen charts which have different numbers of letters on each line.

A visual acuity of 6/6 is frequently described as meaning that a person can see detail from 6 metres (20ft) away the same as a person with "normal" eyesight would see from 6 metres. If a person has a visual acuity of 6/12, he is said to see detail from 6 metres (20ft) away the same as a person with "normal" eyesight would see it from 12 metres (39ft) away.

Healthy young observers may have a binocular acuity superior to 6/6; the limit of acuity in the unaided human eye is around 6/36/2.4 (20/1020/8), although 6/3 was the highest score recorded in a study of some US professional athletes.[26] Some birds of prey, such as hawks, are believed to have an acuity of around 20/2;[27] in this respect, their vision is much better than human eyesight.

When visual acuity is below the largest optotype on the chart, the reading distance is reduced until the patient can read it. Once the patient is able to read the chart, the letter size and test distance are noted. If the patient is unable to read the chart at any distance, he or she is tested as follows:

For example, the recording CF 5' would mean the patient was able to count the examiner's fingers from a maximum distance of 5 feet directly in front of the examiner.

(The results of this test, on the same patient, may vary from examiner to examiner. This is due more so to the size differences of the various examiner's hands and fingers, than fluctuating vision.)

For example, the recording HM 2' would mean that the patient was able to distinguish movement of the examiner's hand from a maximum distance of 2feet directly in front of the examiner.

(The results of the Hand Motion test are often recorded without the testing distance. This is due to the fact that this test is performed after the patient cannot "pass" the Counting Fingers test. At this point, the examiner is usually directly in front of the patient, and it is assumed that the Hand Motion test is performed at a testing distance of 1 foot or less.)

Various countries have defined statutory limits for poor visual acuity that qualifies as a disability. For example, in Australia, the Social Security Act defines blindness as:

A person meets the criteria for permanent blindness under section 95 of the Social Security Act if the corrected visual acuity is less than 6/60 on the Snellen Scale in both eyes or there is a combination of visual defects resulting in the same degree of permanent visual loss.[28]

In the US, the relevant federal statute defines blindness as follows:[29]

[T]he term "blindness" means central visual acuity of 20/200 or less in the better eye with the use of a correcting lens. An eye that is accompanied by a limitation in the fields of vision such that the widest diameter of the visual field subtends an angle no greater than 20 degrees shall be considered for purposes in this paragraph as having a central visual acuity of 20/200 or less.

A person's visual acuity is registered documenting the following: whether the test was for distant or near vision, the eye(s) evaluated and whether corrective lenses (i.e. glasses or contact lenses) were used:

So, distant visual acuity of 6/10 and 6/8 with pinhole in the right eye will be: DscOD 6/10 PH 6/8. Distant visual acuity of count fingers and 6/17 with pinhole in the left eye will be: DscOS CF PH 16/17. Near visual acuity of 6/8 with pinhole remaining at 6/8 in both eyes with spectacles will be: NccOU 6/8 PH 6/8.

"Dynamic visual acuity" defines the ability of the eye to visually discern fine detail in a moving object.

Visual acuity measurement involves more than being able to see the optotypes. The patient should be cooperative, understand the optotypes, be able to communicate with the physician, and many more factors. If any of these factors is missing, then the measurement will not represent the patient's real visual acuity.

Visual acuity is a subjective test meaning that if the patient is unwilling or unable to cooperate, the test cannot be done. A patient who is sleepy, intoxicated, or has any disease that can alter their consciousness or mental status, may not achieve their maximum possible acuity.

Illiterate patients who cannot read letters and/or numbers will be registered as having very low visual acuity if this is not known. Some patients will not tell the examiner that they do not know the optotypes, unless asked directly about it. Brain damage can result in a patient not being able to recognize printed letters, or being unable to spell them.

A motor inability can make a person respond incorrectly to the optotype shown and negatively affect the visual acuity measurement.

Variables such as pupil size, background adaptation luminance, duration of presentation, type of optotype used, interaction effects from adjacent visual contours (or crowding") can all affect visual acuity measurement.

The newborns visual acuity is approximately 6/133, developing to 6/6 well after the age of six months in most children, according to a study published in 2009.[30]

The measurement of visual acuity in infants, pre-verbal children and special populations (for instance, handicapped individuals) is not always possible with a letter chart. For these populations, specialised testing is necessary. As a basic examination step, one must check whether visual stimuli can be fixated, centered and followed.

More formal testing using preferential looking techniques use Teller acuity cards (presented by a technician from behind a window in the wall) to check whether the child is more visually attentive to a random presentation of vertical or horizontal gratings on one side compared with a blank page on the other side the bars become progressively finer or closer together, and the endpoint is noted when the child in its adult carer's lap equally prefers the two sides.

Another popular technique is electro-physiologic testing using visual evoked (cortical) potentials (VEPs or VECPs), which can be used to estimate visual acuity in doubtful cases and expected severe vision loss cases like Leber's congenital amaurosis.

VEP testing of acuity is somewhat similar to preferential looking in using a series of black and white stripes (sine wave gratings) or checkerboard patterns (which produce larger responses than stripes). Behavioral responses are not required and brain waves created by the presentation of the patterns are recorded instead. The patterns become finer and finer until the evoked brain wave just disappears, which is considered to be the endpoint measure of visual acuity. In adults and older, verbal children capable of paying attention and following instructions, the endpoint provided by the VEP corresponds very well to the psychophysical measure in the standard measurement (i.e. the perceptual endpoint determined by asking the subject when they can no longer see the pattern). There is an assumption that this correspondence also applies to much younger children and infants, though this does not necessarily have to be the case. Studies do show the evoked brain waves, as well as derived acuities, are very adult-like by one year of age.

For reasons not totally understood, until a child is several years old, visual acuities from behavioral preferential looking techniques typically lag behind those determined using the VEP, a direct physiological measure of early visual processing in the brain. Possibly it takes longer for more complex behavioral and attentional responses, involving brain areas not directly involved in processing vision, to mature. Thus the visual brain may detect the presence of a finer pattern (reflected in the evoked brain wave), but the "behavioral brain" of a small child may not find it salient enough to pay special attention to.

A simple but less-used technique is checking oculomotor responses with an optokinetic nystagmus drum, where the subject is placed inside the drum and surrounded by rotating black and white stripes. This creates involuntary abrupt eye movements (nystagmus) as the brain attempts to track the moving stripes. There is a good correspondence between the optokinetic and usual eye-chart acuities in adults. A potentially serious problem with this technique is that the process is reflexive and mediated in the low-level brain stem, not in the visual cortex. Thus someone can have a normal optokinetic response and yet be cortically blind with no conscious visual sensation.

Visual acuity depends upon how accurately light is focused on the retina, the integrity of the eye's neural elements, and the interpretative faculty of the brain.[31] "Normal" visual acuity (in central, i.e. foveal vision) is frequently considered to be what was defined by Herman Snellen as the ability to recognize an optotype when it subtended 5 minutes of arc, that is Snellen's chart 6/6-metre, 20/20 feet, 1.00 decimal or 0.0 logMAR. In young humans, the average visual acuity of a healthy, emmetropic eye (or ametropic eye with correction) is approximately 6/5 to 6/4, so it is inaccurate to refer to 6/6 visual acuity as "perfect" vision. 6/6 is the visual acuity needed to discriminate two contours separated by 1 arc minute 1.75mm at 6 metres. This is because a 6/6 letter, E for example, has three limbs and two spaces in between them, giving 5 different detailed areas. The ability to resolve this therefore requires 1/5 of the letter's total size, which in this case would be 1 minute of arc (visual angle). The significance of the 6/6 standard can best be thought of as the lower limit of normal, or as a screening cutoff. When used as a screening test, subjects that reach this level need no further investigation, even though the average visual acuity with a healthy visual system is typically better.

Some people may suffer from other visual problems, such as severe visual field defects, color blindness, reduced contrast, mild amblyopia, cerebral visual impairments, inability to track fast-moving objects, or one of many other visual impairments and still have "normal" visual acuity. Thus, "normal" visual acuity by no means implies normal vision. The reason visual acuity is very widely used is that it is easily measured, its reduction (after correction) often indicates some disturbance, and that it often corresponds with the normal daily activities a person can handle, and evaluates their impairment to do them (even though there is heavy debate over that relationship).

Normally, visual acuity refers to the ability to resolve two separated points or lines, but there are other measures of the ability of the visual system to discern spatial differences.

Vernier acuity measures the ability to align two line segments. Humans can do this with remarkable accuracy. This success is sometimes regarded as hyperacuity. Under optimal conditions of good illumination, high contrast, and long line segments, the limit to vernier acuity is about 8 arc seconds or 0.13 arc minutes, compared to about 0.6 arc minutes (6/4) for normal visual acuity or the 0.4 arc minute diameter of a foveal cone. Because the limit of vernier acuity is well below that imposed on regular visual acuity by the "retinal grain" or size of the foveal cones, it is thought to be a process of the visual cortex rather than the retina. Supporting this idea, vernier acuity seems to correspond very closely (and may have the same underlying mechanism) enabling one to discern very slight differences in the orientations of two lines, where orientation is known to be processed in the visual cortex.

The smallest detectable visual angle produced by a single fine dark line against a uniformly illuminated background is also much less than foveal cone size or regular visual acuity. In this case, under optimal conditions, the limit is about 0.5 arc seconds or only about 2% of the diameter of a foveal cone. This produces a contrast of about 1% with the illumination of surrounding cones. The mechanism of detection is the ability to detect such small differences in contrast or illumination, and does not depend on the angular width of the bar, which cannot be discerned. Thus as the line gets finer, it appears to get fainter but not thinner.

Stereoscopic acuity is the ability to detect differences in depth with the two eyes. For more complex targets, stereoacuity is similar to normal monocular visual acuity, or around 0.61.0 arc minutes, but for much simpler targets, such as vertical rods, may be as low as only 2 arc seconds. Although stereoacuity normally corresponds very well with monocular acuity, it may be very poor, or absent, even in subjects with normal monocular acuities. Such individuals typically have abnormal visual development when they are very young, such as an alternating strabismus, or eye turn, where both eyes rarely, or never, point in the same direction and therefore do not function together.

The eye has acuity limits for detecting motion.[32] Forward motion is limited by the subtended angular velocity detection threshold (SAVT), and horizontal and vertical motion acuity are limited by lateral motion thresholds. The lateral motion limit is generally below the looming motion limit, and for an object of a given size, lateral motion becomes the more insightful of the two, once the observer moves sufficiently far away from the path of travel. Below these thresholds subjective constancy is experienced in accordance with the Stevens' power law and WeberFechner law.

There is a specific acuity limit in detecting an approaching object's looming motion.[33][34] This is regarded as the subtended angular velocity detection threshold (SAVT) limit of visual acuity.[35] It has a practical value of 0.0275 rad/s.[36] For a person with SAVT limit of t {displaystyle {dot {theta }}_{t}} , the looming motion of a directly approaching object of size S, moving at velocity v, is not delectable until its distance D is[33]

where the S2/4 term is omitted for small objects relative to great distances by small-angle approximation.

To exceed the SAVT, an object of size S moving as velocity v must be closer than D; beyond that distance, subjective constancy is experienced. The SAVT t {displaystyle {dot {theta }}_{t}} can be measured from the distance at which a looming object is first detected:

where the S2 term is omitted for small objects relative to great distances by small-angle approximation.

The SAVT has the same kind of importance to driving safety and sports as the static limit. The formula is derived from taking the derivative of the visual angle with respect to distance, and then multiplying by velocity to obtain the time rate of visual expansion (d/dt = d/dx dx/dt).

There are acuity limits ( t {displaystyle {dot {theta }}_{t}} ) of horizontal and vertical motion as well.[32] They can be measured and defined by the threshold detection of movement of an object traveling at distance D and velocity v orthogonal to the direction of view, from a set-back distance B with the formula

Because the tangent of the subtended angle is the ratio of the orthogonal distance to the set-back distance, the angular time rate (rad/s) of lateral motion is simply the derivative of the inverse tangent multiplied by the velocity (d/dt = d/dx dx/dt). In application this means that an orthogonally traveling object will not be discernible as moving until it has reached the distance

where t {displaystyle {dot {theta }}_{t}} for lateral motion is generally 0.0087 rad/s with probable dependence on deviation from the fovia and movement orientation,[32] velocity is in terms of the distance units, and zero distance is straight ahead. Far object distances, close set-backs, and low velocities generally lower the salience of lateral motion. Detection with close or null set-back can be accomplished through the pure scale changes of looming motion.[34]

The motion acuity limit affects radial motion in accordance to its definition, hence the ratio of the velocity v to the radius R must exceed t {displaystyle {dot {theta }}_{t}} :

Radial motion is encountered in clinical and research environments, in dome theaters, and in virtual-reality headsets.

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Visual acuity - Wikipedia

Can you see an optician at this time? (Picture: Getty Images)

Speculation over whether coronavirus can affect your eyesight has been rife since Dominic Cummings claimed he made a trip to Barnard Castle during lockdown amid concerns Covid-19 had affected his eyesight.

Boris Johnson has also suggested his vision had been affected by the virus, after saying in Mondays press briefing that he has had to wear glasses for the first time in years.

All of which may have left others wondering about their own vision, and whether it might have been affected but can you currently go to an optician for an eye test?

Heres what you need to know

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All routine eye tests have been suspended in the wake of lockdown so if you had an eye test booked chances are it wont have happened.

However, some opticians have remained open during this time, with the Government having classed them as being among essential services but only to provide urgent or emergency care where needed, to alleviate pressure on GPs, hospital eye departments and A&E departments.

SpecSavers are among those who have kept some of their branches open for this but have emphasised on their website they have only remained open when it is safe for both our customers and colleagues.

Vision Express are also open for urgent and emergency appointments, with Asda Opticians and Boots Opticians and among others who have remained open for this purpose only but not all branches are open.

In all cases, you are advised not to visit an optician directly, but to to call your local branch if you have a problem, so they can assess your situation and whether or not you need to be seen face to face, either at their branch if its open, or elsewhere.

If your local optician is an independent or belongs to another chain you should also call first to discuss the nature of the problem, and to confirm whether they are open for appointments at this time.

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An urgent or emergency appointment is classed as one where you might need immediate clinical help such as having red eyes, contact lens discomfort, a foreign object in the eye, a sudden change in vision or unexpected flashers or floaters in the eye.

If your glasses or contact lenses are broken and you need replacements, most opticians are currently delivering these to peoples homes free of charge, so that they do not have to visit the branch to collect them.

MORE: Passenger with poor eyesight killed by train after falling from platform

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Are opticians open and can you get an eye test? - Metro.co.uk