If you have eye pain, eye redness that won't clear up with drops, blurry vision, light sensitivity, excessive tearing or feel as if there is something in your eye, you should see your eye doctor.

If untreated, Acanthamoeba keratitis will lead to severe pain and possible vision loss or blindness. In the case of the Denver woman, Stacey Peoples needed a corneal transplant. She now has normal vision with glasses, according to a Today story.

To avoid Acanthamoeba keratitis and all contact lens-related eye infections, be sure to carefully follow the lens care, handling and wearing instructions you receive from your eye doctor.

What Is Acanthamoeba Keratitis?

Acanthamoeba are naturally occurring amoeba (tiny, one-celled animals) commonly found in water sources, such as tap water, well water, swimming pools, hot tubs, and soil and sewage systems.

If these tiny parasites infect the eye, Acanthamoeba keratitis results.

First diagnosed in 1973, an estimated 85 percent of U.S. Acanthamoeba keratitis cases affect contact lens users, according to the Centers for Disease Control and Prevention (CDC). In the developed world, the incidence of Acanthamoeba keratitis is approximately one to 33 cases per million contact lens wearers.

That incidence may be increasing, though.

UK researchers at University College London found that rates of Acanthamoeba keratitis have nearly tripled since 2011 in the southeast of England. Moorfields Eye Hospital, where cases across the southeast of England are treated, recorded an average of 50.3 cases of Acanthamoeba keratitis.

Acanthamoeba Outbreaks Among Contact Lens Wearers

In recent years, the U.S. Centers for Disease Control and Prevention (CDC) and other researchers have noted sporadic outbreaks of Acanthamoeba keratitis cases among contact lens wearers.

In 2007, for example, the CDC released several public health warnings regarding Acanthamoeba keratitis associated with use of the contact lens solution Complete MoisturePlus, manufactured by Abbott Medical Optics (AMO) — formerly Advanced Medical Optics.

The CDC said a sevenfold increase in the risk of developing Acanthamoeba keratitis associated with use of the contact lens solution prompted AMO to withdraw Complete MoisturePlus from the market. The contact lens solution itself was not contaminated, but it seemed to be ineffective in preventing Acanthamoeba keratitis.

The CDC has issued similar warnings concerning fungal eye infections associated with the use of Bausch + Lomb's ReNu With MoistureLoc contact lens solution, which was removed from worldwide markets in May 2006.

In 2011, the CDC and state and local health officials investigated unusual clusters of Acanthamoeba keratitis cases to find common risk factors to reduce future infections. The preliminary analysis found contact lens hygiene practices played a role but did not result in a call to stop the sales of any contact lens-related products.

What Causes Acanthamoeba Keratitis?

Factors and activities that increase the risk of contracting Acanthamoeba keratitis include using contaminated tap or well water on contact lenses, using homemade solutions to store and clean contacts, wearing contact lenses in a hot tub and swimming or showering while wearing lenses.

Acanthamoeba is a single-cell organism that exists in nature in two forms: an active, growing form (left) and a dormant, stress resistant cyst (right). (Images: Morales, Khan and Walochnik [CC BY 2.0 ], via Wikimedia Commons) 

A dirty lens case also can be a source of Acanthamoeba infection.

In addition, some scientists theorize that new U.S. Environmental Protection Agency regulations aimed at reducing carcinogenic (potentially cancer-causing) products such as disinfectants in the water supply may have inadvertently boosted microbial risks, including an increased likelihood of finding Acanthamoeba in water supplies.

Other researchers associate recent increases in contact lens-related eye infections with the introduction of "no-rub" lens care systems that may result in less effective contact lens cleaning and disinfection.

But regardless of the cause of the increase, Acanthamoeba can be killed easily, especially when rubbed off the lens surface during cleaning. In the end, good contact lens hygiene is the best way to prevent Acanthamoeba keratitis.

How Do You Know if You Have Acanthamoeba Keratitis?

Symptoms of Acanthamoeba keratitis include red eyes and eye pain after removing your contact lenses, as well as tearing, light sensitivity, blurred vision and a feeling that something is in your eye.

With these types of symptoms, you should always contact your eye doctor. But keep in mind that Acanthamoeba keratitis is often difficult for your eye doctor to diagnose at first, because its symptoms are similar to pink eye symptoms and those of other eye infections.

Diagnosis of keratitis often occurs once it is determined that the condition is resistant to antibiotics used to manage other infections. A "ring-like" ulceration of your corneal tissue may also occur.

Unfortunately, if not promptly treated, Acanthamoeba keratitis can cause permanent vision loss or require a corneal transplant to recover lost vision.

How You Can Reduce the Risk of Getting Acanthamoeba Keratitis

There are several easy ways to greatly reduce the chance of getting this sight-threatening condition — and, in fact, any type of contact lens-related eye infection:

Remember to also clean and sterilize your lens cases, to avoid Acanthamoeba contamination.

1. Follow your eye doctor's recommendations regarding care of your contact lenses. Use only products that he or she recommends.

2. Never use tap water with your contact lenses. The  FDA
    has recommended that contact lenses should not be exposed to water of any kind.

3. Do not swim, shower or use a hot tub while wearing contacts. If you do decide to wear your lenses while swimming, wear airtight  swim goggles over them. (Read about additional strategies for swimming with contact lenses.)

4. Soak your lenses in fresh disinfecting solution every night. Don't use a wetting solution or saline solution that isn't intended for disinfection.

5. Always wash your hands before handling your lenses.

6. Always clean your contacts immediately upon removal (unless you are wearing  disposable contact lenses that are replaced daily). To clean your lenses, rub the lenses under a stream of multipurpose solution — even if using a "no-rub" solution — and store them in a clean case filled with fresh (not "topped off") multipurpose or disinfecting solution.

Take Care of Your Contact Lens Case

Cleanliness and proper care are equally important for contact lens cases.

It's important to clean, rinse and air-dry your contact lens case immediately after removing your lenses from the case. Discard the old solution and rub the inside wells of the case with clean fingers for at least five seconds. Then fill the case with multipurpose solution or sterile saline (not tap or bottled water), dump this out, and store the case upside down with the caps off.

As an extra precaution, you might want to consider sterilizing your empty contact lens case once a week by submerging it in boiling water for a few minutes.

Many eye doctors also say you should discard and replace your contact lens case monthly or, at a minimum, every three months to help prevent contamination.

Prevention is your best defense against Acanthamoeba keratitis. Always use good hygiene during contact lens use and care.

From Coopervision: Millions of children across Canada are poised to benefit from a breakthrough therapy that addresses the fast-growing issue of myopia (nearsightedness), which is projected to negatively affect more than 50 percent of the world’s population by 2050.

CooperVision MiSight® 1 day contact lenses are now available for fitting by Eye Care Professionals. It is the world’s first one-day soft contact lens clinically proven to substantially slow the progression of myopia in children.

Myopia significantly increases the risk of retinal detachment and myopic maculopathy, with even low myopia levels associated with a higher prevalence of glaucoma and cataracts3. MiSight® 1 day has been shown to reduce myopia progression by more than half versus a single-vision one-day lens1,4. Over three years, children wearing MiSight® 1 day had 59 percent less myopia progression and 52 percent less axial elongation on average than those wearing a single-vision one-day lens1.

The innovative contact lens is designed for children who have a myopia prescription from -0.25 to -6.00. Its ActivControl® Technology addresses both axial elongation and refractive error4.

Ease of Fitting, Wear and Care

For Eye Care Professionals, MiSight® 1 day is as easy to fit as a single-vision soft contact lens. They benefit from repeatable outcomes with minimal chair time and follow-up visits, compared to therapies such as OrthoK.

References:

1 Chamberlain P, Logan N, Jones D, Gonzalez-Meijome J, Saw S-M, Young G. Clinical evaluation of a dual-focus myopia control 1 day soft contact lens: 3-year results. Presented at: British Contact Lens Association Clinical Conference, Liverpool, England.

2 Holden BA, Fricke TR, Wilson DA, et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016;123(5):1036-1042.

3 Flitcroft DI. The complex interactions of retinal, optical and environmental factors in myopia aetiology. Prog Retin Eye Res. 2012;31(6):622-660.

4 Data on file, CooperVision.

5 Children ages 8-15.

Struggling to see comfortably at night? Call us for more information on the new Zeiss DriveSafe Lenses!

ZEISS DriveSafe

One pair of glasses for everyday use and safer driving.

Most drivers are exposed to difficult driving conditions that impact their vision, including driving in rain, snow or fog, and of course driving at night. For most, this can be a major source of stress - in fact, over two thirds of adults report difficulty driving in these challenging visual conditions. ZEISS DriveSafe, an all-day lens and coating solution designed for patients who need the most help with vision while driving. ZEISS DriveSafe’s unique technology addresses the most stressful visual challenges drivers face today.

ZEISS DriveSafe is available in both single vision and progressive lens types. 

May is Vision Awareness Month. More than 20 million Americans suffer from severe vision loss. While not all eye diseases can be prevented, there are simple steps that everyone can take to help their eyes remain healthy now and reduce their chances of vision loss in the future.

Here are the top 10 tips from the American Academy of Ophthalmology to safeguard your vision:

1.Wear sunglasses
UV blocking sunglasses delay the development of cataracts, since direct sunlight hastens their formation. Sunglasses prevent retinal damage; they also protect the delicate eyelid skin to prevent both wrinkles and skin cancer around the eye, and both cancerous and non-cancerous growths on the eye. Check for 100 percent UV protection: Make sure your sunglasses block 100 percent of UV-A rays and UV-B rays.

2. Don’t smoke
Tobacco smoking is directly linked to many adverse health effects, including age-related macular degeneration (AMD). Studies show that current smokers and ex-smokers are more likely to develop AMD than people who have never smoked. Smokers are also at increased risk for developing cataracts.

3. Eat right
Vitamin deficiency can impair retinal function. The belief that eating carrots improves vision has some truth, but a variety of vegetables, especially leafy green ones, should be an important part of your diet. Researchers have found people on diets with higher levels of vitamins C and E, zinc, lutein, zeaxanthin, omega-3 fatty acids DHA and EPA are less likely to develop early and advanced AMD.

4. Baseline eye exam
Adults with no signs or risk factors for eye disease should get a baseline eye disease screening at age 40 — the time when early signs of disease and changes in vision may start to occur. Based on the results of the initial screening, an ophthalmologist will prescribe the necessary intervals for follow-up exams. Anyone with symptoms or a family history of eye disease, diabetes or high blood pressure should see an ophthalmologist to determine how frequently your eyes should be examined.

5. Eye protection
An estimated 2.5 million eye injuries occur in the U.S. each year, so it is critical to wear proper eye protection to prevent eye injuries during sports such as hockey and baseball and home projects such as home repairs, gardening, and cleaning. For most repair projects and activities around the home, standard ANSI-approved protective eyewear will be sufficient. Sports eye protection should meet the specific requirements of that sport; these requirements are usually established and certified by the sport’s governing body and/or the American Society for Testing and Materials (ASTM).

6. Know your family history
Many eye diseases cluster in families, so you should know your family’s history of eye disease because you may be at increased risk. Age-related eye diseases, including cataracts, diabetic retinopathy, glaucoma and age-related macular degeneration are expected to dramatically increase — from 28 million today to 43 million by the year 2020.

7. Early intervention
Most serious eye conditions, such as glaucoma and AMD, are more easily and successfully treated if diagnosed and treated early. Left untreated, these diseases can cause serious vision loss and blindness. Early intervention now will prevent vision loss later.

8. Contact lens care
Follow your ophthalmologist’s instructions regarding the care and use of contact lenses. Abuse, such as sleeping in contacts that are not approved for overnight wear, using saliva or water as a wetting solution, using expired solutions, and using disposable contact lenses beyond their wear can result in corneal ulcers, severe pain and even vision loss.

9. Be aware of eye fatigue
If you have eye strain from working at a computer or doing close work, you can follow the 20-20-20 rule: Look up from your work every 20 minutes at an object 20 feet away for twenty seconds. If eye fatigue persists, it can be a sign of several different conditions, such as dry eye, presbyopia, or spectacles with lenses that are not properly centered. See an ophthalmologist to determine why you are having eye fatigue and to receive proper treatment. If you don’t already have an ophthalmologist, Find an ophthalmologist in your area. Consumers can submit questions about eye health to an ophthalmologist at Ask an ophthalmologist.

From Zeiss Canada:

Blue Light: the Good and the Bad

How much blue light do we need? And how and when should we be protecting ourselves against it? Can blue light blocking glasses or lenses help?

A debate is raging over the beneficial and damaging effects of blue light. On the one hand, blue light can be a helpful tool in combating seasonal depression and insomnia. On the other hand, blue light can permanently damage the human eye. So what's the deal with blue light? And what has changed about the artificial light we experience every day? Why do our bodies need the biological effects of this wavelength? And how and when should we protect ourselves from the potentially damaging effects of blue light? Read on to find out more about the good and the bad of blue light.  

The visible spectrum

The light that reaches and enters the human eye is divided into visible light, comprising wavelengths from 380 to 780 nm, and non-visible light, which includes light in the ultraviolet range (UV light) and the infrared range (IR light).

Experts have been aware for some time that UV light can potentially damage biological tissue, such as our skin and eyes. That is why people typically take precautions to protect themselves from the sun, using items such as sunscreen or a pair of sunglasses. However, visible blue-violet light also has the potential to cause damage to our eyes. Although blue-violet light has less energy than ultraviolet light, it is almost entirely unfiltered as it passes through the eye and reaches the retina. By way of contrast, ultraviolet light is almost entirely absorbed by the front part of the eye, and significantly less than 5% of it reaches as far as the retina.

The blue component of light between 380nm and 500nm is also known as high-energy visible (HEV) light. In particular blue-violet wavelengths between 380nm and 440nm are seen as potentially damaging and have been implicated as one of the possible causes of photoretinitis, i.e. damage to the retina caused by high-energy incident light. 

Beneficial aspects of blue light

Light does more than just help us see, it is also an important means of regulating our biological rhythms and affects our general well-being. Light influences whether or not we are awake, focused, productive, and feel energized and healthy.

Scientific studies have confirmed the biological effect of light on our body. Ultraviolet light, for example, influences the production of vitamins. Exposure to bright light and, in particular, the portion of blue light affects our hormonal balance. Hormones in the body regulate how a person feels as well as their sleep-wake cycle. In daylight, the portion of blue light is relatively high, whereas it is significantly reduced in the evening.

When it's bright outside, the body releases serotonin – also known as one of the "happy hormones" – and cortisol, a stress hormone. Both of these make us feel awake and active. However, melatonin is considered a sleep hormone and causes us to feel tired and sleep soundly when it is dark.

Light, in particular blue light that reaches the retina, also affects our psychological well-being. That is why light therapy is successfully employed to treat winter depression and insomnia. But, as is so often the case, the axiom "everything in moderation" still applies. Exposure to too much light also carries certain risks and can even be damaging. 

Damaging effects of blue light

Too much light in the ultraviolet and blue-violet bands can damage the human eye. As well as leading to painful inflammation of the conjunctiva and cornea, it can also cause damage to the eye's crystalline lens (e.g., cataracts) and especially to the retina (macular degeneration).

That's why it is so important to wear sunglasses with 100% UV protection in strong sunshine, especially in situations where there is a lot of glare such as on water or snowy mountain slopes. 

The modern world: light sources with a high proportion of blue light

From light-emitting diodes (LEDs) and xenon light to energy-saving bulbs and electromagnetic radiation from screens, all the "new light sources" that are designed to make our lives better and easier contain a higher proportion of blue light than the old traditional light bulbs. The different spectral composition of the light means that we are exposed to significantly more blue light than before. Could this be having a detrimental effect on our eyesight?

But it is important to remember  that spending one hour outside on a normal overcast day exposes our eyes to 30 times more blue light than spending one hour inside sitting in front of a screen.

Clear eyeglass lenses with a blue light filter: blue light blocking lenses

It is now possible to get clear lenses with a blue light filter, such as DuraVision® Blue Protect. But why should we?

Blue light radiation from light sources or screens can be irritating or tiring for some people's eyes. A blue filter can provide people with sharper vision: the different wavelengths of visible light are refracted in slightly different ways by the cornea and crystalline lens, so not all of them strike the same focal point on the retina. Some people will be familiar with these phenomena – for example, the fact that it's easier to clearly see red at a distance and blue close up, or the way in which infographics with red, green and blue lines are more tiring to keep in focus than lines which are all shaded in the same or similar colors.

Some people find that light sources with a high proportion of blue light can make them feel more restless at night. When we find ourselves in a dark room or outside at dusk or at night-time, our eyes switch to a different mode of vision. In low_light the human eye shifts from green sensitivity to the high-energy blue spectrum. That means we perceive blue light more intensely, which can give the sensation of increased glare. This effect will be familiar to drivers who have been blinded by the glaring headlights of oncoming vehicles, especially those with modern xenon or LED headlights. Eyeglass lenses with a blue light filter can create more comfortable vision in these situations.

DuraVision BlueProtect is a lens coating for clear lenses which can be applied as an additional layer to create blue light blocking glasses. It offers all the benefits of a traditional DuraVision Premiumcoating by ZEISS, including optimized hardness in an easy-clean design. BlueProtect also includes a blue filter which attenuates blue light in the 380 to approx. 450 nm band. That means improved visual comfort for anyone who wants protection against blue light during indoor activities without losing the beneficial effects of blue light in the approx. 450 to 500 nm band! Eyeglasses with DuraVision BlueProtect can be worn all day long, unless you choose to wear your sunglasses for outdoor activities or use PhotoFusion lenses, which also offer 100% UV protection.

How digital devices are changing our vision

Tablets, smart phones and other digital displays are not only changing the light spectrum we are exposed to – they are also changing our visual behavior. It's important to recognize that we are spending far more time looking at things "close up" than we did before. That's often because the background brightness is too low. This is even a problem among children: "school myopia" refers to the increasing propensity of children to suffer from short-sightedness once they start school. 

If we fail to spend enough time looking into the distance, then our eyes don't get as much opportunity to relax, and we essentially "unlearn" the ability to focus quickly for various distances. That causes digital eye strain. In addition, we naturally blink less when we're staring at digital displays, so our cornea is moistened less frequently by tear fluid. This can lead to tired, strained eyes. And in the worst case it can even impair our vision.

Our tip: We recommend giving your eyes frequent breaks by looking into the distance often – even when you are in the middle of working on your laptop, tablet or smartphone. And make sure your eyes are exposed to enough brightness while ensuring they are adequately protected against excessive UV and blue-violet light.