contact lens

Contacts May One Day Be Used to Deliver Glaucoma Medication.

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A special type of contact lens has been designed to gradually deliver medication to the eye, researchers report.

This kind of contact lens could help people who have a hard time using eye drops to treat conditions such as glaucoma, the study authors explained.

The new study showed that the drug-dispensing lenses were able to effectively lower the eye pressure in monkeys with glaucoma at least as much as the standard eye drops used to treat the disease.

“This promising delivery system removes the burden of administration from the patient and ensures consistent delivery of medication to the eye, eliminating the ongoing concern of patient compliance with dosing,” study co-author Dr. Janet Serle said in a news release from the Massachusetts Eye and Ear Infirmary. Serle is a glaucoma specialist at Icahn School of Medicine at Mount Sinai in New York City.

Glaucoma is a group of diseases where increased pressure in the eye damages the optic nerve, according to the U.S. National Eye Institute. It’s the number one cause of irreversible blindness around the world. There is no cure for this disease, but treatment can reduce pressure in the eye and help prevent vision loss.

Right now, glaucoma medications only come in eye drops. Patients who have trouble with eye drops may not use their medication as directed by their doctor, the researchers pointed out.

“If we can address the problem of [people not using their eye drops as directed], we may help patients adhere to the therapy necessary to maintain vision in diseases like glaucoma, saving millions from preventable blindness,” said study first author Dr. Joseph Ciolino. He’s an ophthalmologist at Massachusetts Eye and Ear and an assistant professor of ophthalmology at Harvard Medical School in Boston.

“This study also raises the possibility that we may have an option for glaucoma that’s more effective than what we have today,” Ciolino said.

For the study, researchers tested the effectiveness of medicated contacts in four monkeys with glaucoma. The drug-administering contact lenses have a medicated polymer film that slowly delivered the glaucoma medication, latanoprost, to the monkeys’ eyes.

The study found the contacts with lower doses of latanoprost reduced eye pressure as much as the eye drop version of the medication. And lenses that dispensed higher doses of the drug resulted in greater reduction of eye pressure than the eye drops.

Dr. Daniel Kohane, the study’s senior author, said that “instead of taking a contact lens and allowing it to absorb a drug and release it quickly, our lens uses a polymer film to house the drug, and the film has a large ratio of surface area to volume, allowing the drug to release more slowly.” Kohane is director of the Laboratory for Biomaterials and Drug Delivery at Boston Children’s Hospital.

The drug in the medicated contacts is stored in the lenses’ outer edges, leaving the center of the lens clear. As a result, the drug in the contacts doesn’t impair vision, hydration or breathability. The contacts could be customized for each patient with a prescription to correct vision or not, the study authors said.

The researchers had previously shown in a 2014 study that the lens is capable of delivering medication continuously for one month.

More research is needed to confirm the new findings, particularly because animal research often doesn’t produce similar results in humans. The study authors plan to test the safety and effectiveness of the drug-dispensing contacts on people.

41 million Americans could be putting themselves at risk for permanent eye damage – and it’s largely preventable

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When people ask me why I don’t wear contacts, I typically come up with some excuse to avoid admitting the truth: that sticking a plastic device directly on the fragile mucous membrane surrounding my cornea terrifies me.

But it does, and it’s the reason I’ve always felt A-OK just wearing glasses.

contact lens, eye

A new report from the Centers for Disease Control and Prevention makes me feel a little justified in my fear of contacts, despite the fact that they’re largely safe and effective – at least when worn correctly.

The report builds on previous findings from 2014, when the CDC found that more than 99% of the contact lens wearers they surveyed reported at least one behavior that put them at risk for an eye infection. Forty-one millions Americans don’t share my fear, opting to use contacts on the regular.

According to the new study, which looked at 1,075 reported infections related to wearing contacts, many of these infections can lead to long-lasting damage. On the bright side, they’re typically preventable.

Here were their main findings:

About 1 in 5 reports included someone who’d had a scarred cornea, needed a corneal transplant, or had reduced vision.

Roughly 20% of the reported infections included someone who’d had severe problems with their cornea, the eye’s clear front dome. The corneaplays a key role in clear vision and has a remarkable capacity to recover from most minor nicks. But an infection – like the ones described in the CDC’s report – can damage the cornea’s deeper layers, making it tough to completely heal.

In some cases, corneal damage can also cause scarring, which can distort your vision. When the scarring is severe, you may need a corneal transplant, which involves swapping part of your cornea with tissue from a donor.

More than 1 in 4 reports mentioned contact lens habits that are known to increase the chance of getting an infection.

While these problems sound severe, most of them are potentially preventable. For example, the report found that many users reported sleeping in their contact lenses when not prescribed and wearing lenses for longer than the prescribed period.

“Contact lens wearers can reduce their risk for contact lens-related infections by improving their hygiene behaviors, such as not sleeping in contact lenses unless prescribed and replacing their contact lenses as prescribed,” the report states.

So next time you get up to put on your contacts, remember – you’re putting in a medical device, and you should handle it with care.

Here are some simple tips for good contact lens hygiene:

1. Wash your hands before handling your lenses.

2. Completely replace yesterday’s contact solution.

3. Wear your contacts for only as long as they’re prescribed.

4. Rinse your lens case with contact solution and wipe it out with a clean towel after every use.

Google Patents for contact lens that can scan your Iris

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Google’s love for contact lenses is never ending. The search engine giant has already done considerable work on contact lenses and their use in health applications.

Now, Google has patented a new technology that transforms contact lenses into an identification device.

This new technology involves covering all parts of the iris of an eye. The contact lens surface contains one or more light sensors that are embedded on its surface and these reflect off light from the iris.

google-contact-lens-iris-fingerprint

These sensors collect an image of the iris and it is then compared with the image of same iris saved in computer’s memory. If a match between the two images is found then a door for the wearer will be unlocked or else a file containing sensitive information might become accessible.

Specifications about the technology’s applications haven’t been disclosed in the patent. Presumably, the lenses will be used for biometric authentications in numerous contexts.

Google has been testing smart contact lenses, which can be used one day by diabetics for measuring their blood sugar levels. In such type of lens, a small chip along with sensors is embedded between two coats of lens material. Tears touch the sensors through a small perforation in the material of the lens and thus, the sensors acquire blood sugar levels form the liquid. Through this lens, blood sugar level can be tested once every second.

Watch the video.URL: https://youtu.be/pYD1Mkdm_1E

Contact Lens With Built-In Zoom Designed To Treat Macular Degeneration; Are Wink-Controlled Lenses The Future Of Eyewear?

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Contact lenses with a built-in zoom may change the future of vision. An international team of researchers developed contact lenses zooming capablities and presented the futuristic device at the American Association for the Advancement of Science’s (AAAS) annual meeting in California on Friday.

Zoom In Contact Lenses

The first lens prototype was unveiled in 2013, but it has been significantly improved since then, and now comes with smart glasses. The 1.55-millimeter-thick contact lens contains a tiny reflective telescope, which is activated by a single wink of the eye. It looks like something out of a sci-fi movie or futuristic James Bond sequel.

When light hits the lens, small mirrors bounce light around and change how the user perceives the size of objects, magnifying the entire view. The researchers compared it to looking through low-level magnification binoculars. The lenses only work with smart glasses that respond to the wearer’s winks — the right eye to turn on the zoom and the left eye to deactivate it, bringing it back to a normal visual level. The glasses send images to the retina through hundreds of nerves, which convert light into electric impulses. The moment the signals are converted and transmitted to the brain, the user is able to “see.”

The Future Of Vision

“We think these lenses hold a lot of promise for low vision and age-related macular degeneration,”said the team’s presenter Eric Tremblay, from the Ecole Polytechnique Federale de Lausanne in Switzerland, in a press release. “At this point this is still research, but we are hopeful it will eventually become a real option for people with AMD.”

Age-related macular degeneration (AMD), a vision disorder that affects older people, is the leading cause of vision loss for people aged 50 and older, according to the National Eye Institute. As people age, some experience damage to the macula, which is the tiny spot in the back of the eye responsible for seeing fine detail and color. AMD doesn’t lead to complete blindness, but it does severely impair a person’s ability to see, eventually interfering with facial recognition, driving, reading, writing, cooking, and other tasks.

The new device, which researchers called “a huge leap forward” has the power to magnify objects up to 2.8 times. The Pentagon funded the research, but not with elderly peoples’ eyesight in mind. They were originally designed to serve as a form of bionic vision for soldiers, but have since become a revolutionary treatment solution for a rapidly growing older population. Because it was first designed with the intent of helping American soldiers, the cost of the zoom-in lens for the average person will need to be considerably lowered in order to make it not only wearable but also affordable.

“It’s very important and hard to strike a balance between function and the social costs of wearing any kind of bulky visual device,” Tremblay said. “There is a strong need for something more integrated, and a contact lens is an attractive direction.”

The idea of zoom-in lenses isn’t unique to this research team’s efforts, however older models required users to tilt their heads or position their eyes to activate the magnification. Other visual aid inventions that were presented at the AAAS conference were said to have the potential to help 285 million people with vision impairments throughout the world. The team’s goal is to begin clinical trials by 2016 in collaboration with Paris-based Pixium Vision.

“Our chips are already working well in animals,” said researcher Daniel Palanker of Stanford University in California. The team has already been able to restore vision in blind rats about halfway, which is good progress considering “there is currently no solution for patients with macular degeneration.”

Contact lens with… inbuilt telescope to increase peripheral vision 3-fold in a wink — RT News

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Reuters / Brian Snyder

A revolutionary new contact lens with a built in telescope could help millions to regain their full sight. Just a wink of one’s eye is enough to zoom in or turn the telescope off, which increases peripheral vision three fold.

The new technology is set to help sufferers of age-related macular degeneration (AMD), which can result in the loss of vision in the center of the visual field. This makes it difficult to read and recognize faces.

The 1.55mm thick lens contains an extremely thin, reflective telescope. Small mirrors inside bounce light around, expanding the perceived size of objects and magnifying the view, similar to looking through low-magnification binoculars.

It is very simple to operate with the lens working in conjunction with glasses. A simple wink of the right eye makes the telescope zoom in, while if the user winks with their left eye, then the telescope is turned off.

“The most compelling reason why you would want to have this is to help people with serious visual problems, such as macular degeneration, or other retinal illnesses where people have severe vision loss,”said Dr. Eric Tremblay, who is a designer with the Swiss Federal Institute of Technology, which is based in Lausanne.

“In a lot of cases magnification is very useful. So what people usually use are head-mounted telescopes which don’t work for everything,” which was reported by the Daily Telegraph.

The contact lens had an unlikely source for funding, with DARPA, the Pentagon’s research agency providing the cash. They wanted it to be developed to give soldiers a form of bionic vision.

“They were really interested in supervision, but the reality is more tame than that,” said Tremblay at the American Association for the Advancement of Science in San Jose. So far, only five people have tested the latest version, according to the Guardian.

View image on Twitter

There are currently telescope glasses on the market, however they have proved to be cumbersome and expensive for the public, with the technology on sale at $9,240. The new makers of the lens say the new design will be much cheaper. However, it will need some more work before it can be sod publicly as the user can only currently wear it for 30 minutes, as it blocks oxygen to the eye.

Cathy Yelf, the acting CEO of the Macular Society, said: “There is virtue in having a zoomable contact lens for some people with macular degeneration who have lost their central vision. We will be interested to see how, in practice, it works for people with AMD. With an ageing population, investment in research and new treatments is a pressing issue as there,” she said.

Do’s and Don’ts for Contact Lens Wearers .

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Even though your daily contact lens routine may seem to be working well, experts say some common practices can be threatening to eye health.

“It’s a lack of information,” says ophthalmologist Jeffrey Goshe, MD. “People aren’t being told to do most of the things that are standard for contact lens care.”

Dr. Goshe shares these do’s and don’ts for safe contact lens use:

1. DON’T sleep in your contacts

“Despite what manufacturers say about lenses that are safe to sleep in, almost every study of contact lens-related infections found a strong link between the risk of infection and sleeping in contacts,” says Dr. Goshe.

“It’s a period of decreased oxygen flow to the eye.  There are newer lenses that are approved for continuous wear up to thirty days, but I still recommend that my patients remove their contacts on a daily basis.”

2. DO get an eye exam annually

“If your contact lenses are too loose or too tight, you can have problems,” says Dr. Goshe.

People may not realize that the fit of their lenses can change throughout their lives, and an annual check-up can determine if adjustments should be made.

contact lens case

3. DO establish a relationship with an optometrist and stick with him or her

When you jump around from doctor to doctor based on who’s offering a glasses coupon, you won’t have continuity of care that’s necessary to track your eye health over time.

If problems do occur, go to an optometrist or ophthalmologist, not an urgent care center.

4. DON’T wear your lenses past their recommended use

“Some people say they wear them until they feel like they need to be changed,” says Dr. Goshe.“But that’s a sign that something bad has already started to happen.

”That could be abrasion to your cornea or bacteria building up on the inside of your lens. “It’s like putting a dirty band-aid on your eye,” he says.  “If your lenses are designed to be replaced every two weeks, you should replace them at least that often.”

5. DO wash your lenses and case properly

Never rinse your contacts with tap water or stick them in your mouth. Tap water is not sterile and may contain organisms that can cause very severe infections.

Contact lenses should be cleaned with a commercial contact lens solution, following the instructions provided by the manufacturer. Clean and dry your case each day and fill it with new solution rather than “topping off” the solution from the previous day.

6. DON’T ignore the warning signs of infection

“If you are experiencing pain, redness, blurriness or light sensitivity, your eyes may be having a problem that requires medical attention,” Dr. Goshe says.

As a rule of thumb, if any of these symptoms persists for more than 24 hours, I recommend that patient be seen as soon as possible by an optometrist or ophthalmologist. If the symptoms are severe, regardless of the duration, the patient should be seen immediately.

“If treated promptly, the majority of contact lens-related problems don’t lead to long-term vision problems.  However, in severe cases scarring, reduced vision, or blindness can result,” Dr. Goshe says.

By knowing the facts, you can comfortably wear contact lenses without strain or injury to your eyes.

Contact lens merges plastics and active electronics via 3-D printing

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As part of a project demonstrating new 3-D printing techniques, Princeton researchers have embedded tiny light-emitting diodes into a standard contact lens, allowing the device to project beams of colored light.

Michael McAlpine, the lead researcher, cautioned that the lens is not designed for actual use—for one, it requires an external power supply. Instead, he said the team created the device to demonstrate the ability to “3-D print” electronics into complex shapes and materials.

“This shows that we can use 3-D printing to create complex electronics including semiconductors,” said McAlpine, an assistant professor of mechanical and aerospace engineering. “We were able to 3-D print an entire device, in this case an LED.”

The hard is made of plastic. The researchers used tiny crystals, called quantum dots, to create the LEDs that generated the colored light. Different size dots can be used to generate various colors.

“We used the quantum dots [also known as nanoparticles] as an ink,” McAlpine said. “We were able to generate two different colors, orange and green.”

The contact lens is also part of an ongoing effort to use 3-D printing to assemble diverse, and often hard-to-combine, materials into functioning devices. In the recent past, a team of Princeton professors including McAlpine created a bionic ear out of living cells with an embedded antenna that could receive radio signals.

Yong Lin Kong, a researcher on both projects, said the bionic ear presented a different type of challenge.

McAlpine and Yong Lin Kong, a graduate student in mechanical and aerospace engineering, use a custom-built 3-D printer to create the electronics described in their research. Credit: Frank Wojciechowski

“The main focus of the project was to demonstrate the merger of electronics and biological materials,” said Kong, a graduate student in mechanical and aerospace engineering.

Kong, the lead author of the Oct. 31 article describing the current work in the journal Nano Letters, said that the contact lens project, on the other hand, involved the printing of active electronics using diverse materials. The materials were often mechanically, chemically or thermally incompatible—for example, using heat to shape one material could inadvertently destroy another material in close proximity. The team had to find ways to handle these incompatibilities and also had to develop new methods to print electronics, rather than use the techniques commonly used in the electronics industry.

“For example, it is not trivial to pattern a thin and uniform coating of nanoparticles and polymers without the involvement of conventional microfabrication techniques, yet the thickness and uniformity of the printed films are two of the critical parameters that determine the performance and yield of the printed active device,” Kong said.

To solve these interdisciplinary challenges, the researchers collaborated with Ian Tamargo, who graduated this year with a bachelor’s degree in chemistry; Hyoungsoo Kim, a postdoctoral research associate and fluid dynamics expert in the mechanical and aerospace engineering department; and Barry Rand, an assistant professor of electrical engineering and the Andlinger Center for Energy and the Environment.

McAlpine said that one of 3-D printing’s greatest strengths is its ability to create electronics in complex forms. Unlike traditional electronics manufacturing, which builds circuits in flat assemblies and then stacks them into three dimensions, 3-D printers can create vertical structures as easily as horizontal ones.

“In this case, we had a cube of LEDs,” he said. “Some of the wiring was vertical and some was horizontal.”

To conduct the research, the team built a new type of 3-D printer that McAlpine described as “somewhere between off-the-shelf and really fancy.” Dan Steingart, an assistant professor of mechanical and and the Andlinger Center, helped design and build the new printer, which McAlpine estimated cost in the neighborhood of $20,000.

McAlpine said that he does not envision 3-D printing replacing traditional manufacturing in electronics any time soon; instead, they are complementary technologies with very different strengths. Traditional manufacturing, which uses lithography to create electronic components, is a fast and efficient way to make multiple copies with a very high reliability. Manufacturers are using 3-D printing, which is slow but easy to change and customize, to create molds and patterns for rapid prototyping.

Prime uses for 3-D printing are situations that demand flexibility and that need to be tailored to a specific use. For example, conventional manufacturing techniques are not practical for medical devices that need to be fit to a patient’s particular shape or devices that require the blending of unusual materials in customized ways.

“Trying to print a cellphone is probably not the way to go,” McAlpine said. “It is customization that gives the power to 3-D printing.”

In this case, the researchers were able to custom 3-D print electronics on a contact lens by first scanning the lens, and feeding the geometric information back into the printer. This allowed for conformal 3-D printing of an LED on the contact lens.

Terminator Eyes: Hi-tech contact lenses show texts and maps.

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Iafp-photo-torsten-blackwoodmagine texting while driving, or placing a call while showering, without holding your phone in your hands. It’s not sci-fi any more – a new technology allows information like text messages and driving directions to be projected onto a contact lens.

The hardware behind this invention is a spherical curved LCD display that can fit into a contact lens, developed by Ghent University‘s Centre of Microsystems Technology in Belgium.

“This is not science fiction,” chief researcher for the project Jelle De Smet told the Telegraph. “This will never replace the cinema screen for films. But for specific applications it may be interesting to show images such as road directions or projecting text messages from our smart phones straight to our eye.”

These lenses may hit the market within the next few years. In an upgrade from previous models, a new LCD display allows the entire curved surface of the lens to be used.

Earlier versions were based on LEDs, where the display resolution would be limited to only a small number of pixels.

The University of Washington has also been developing new generation of contact lenses that would receive emails and would be able to project information from the Internet, much like in the movie ‘Terminator.’

Other uses of the lens include the concept of adaptable sunglasses – the contact lenses would darken on exposure to light. The lenses could also be used in the fields of medicine and cosmetics.

These advances mark the push for a much wider development of the technology, with the aim of creating a fully pixelated contact lens display as detailed as a television screen.

Tech giants such as Google and Apple have been working to develop similar technology. This past year, Google introduced Project Glass – frames for eyeglasses that project a small computer display into a person’s field of vision. Apple has reportedly patented similar innovations.

Source: http://rt.com

Contact lenses bestow telescopic vision.

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Researchers have created contact lenses which, when paired with special spectacles, bestow telescopic vision on their wearers.

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The contact-lens-and-spectacles combination magnifies scene details by 2.8 times.

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Polarising filters in the spectacles allow wearers to switch between normal and telescopic vision.

The telescopic sight system has been developed to help people suffering age-related blindness.

Age-related macular degeneration is one of the most common forms of blindness and damages the part of the eye, the macula, that handles fine detail. As this area degenerates, sufferers lose the ability to recognise faces and perform tasks, such as driving and reading, that rely on picking up details.

Precise control

The contact lens created by the researchers has a central region that lets light through for normal vision. The telescopic element sits in a ring around this central region. Tiny aluminium mirrors scored with a specific pattern act as a magnifier as they bounce the light around four times within the ring before directing it towards the retina.

In ordinary use, the magnified image is not seen as it is blocked by polarising filters set in a companion pair of spectacles. Wearers can switch it on by changing the filters on the spectacles so the only light falling on their retina comes from the magnified stream.

For their filtering system, the researchers, led by Joseph Ford at UC San Diego and Eric Tremblay at Switzerland’s EPFL, adapted a pair of glasses that Samsung produces for some of its 3D TV sets. In normal use, these spectacles create a 3D effect by alternately blocking the right or left lens.

The prototype contact lens produced by the team is 8mm in diameter, 1mm thick at its centre and 1.17mm thick in its magnifying ring.

“The most difficult part of the project was making the lens breathable,” Dr Tremblay told the BBC. “If you want to wear the lens for more than 30 minutes you need to make it breathable.”

Gases have to be able to penetrate the lens to keep the parts of the eye covered by the contact, especially the cornea, supplied with oxygen, he said.

The team has solved this problem by producing lenses riddled with tiny channels that let oxygen flow through.

However, said Dr Tremblay, this made manufacturing the lenses much more difficult.

“The fabrication tolerances are quite challenging because everything has to be so precise,” he said.

Despite this, gas-permeable versions of the telescopic lens are being prepared that will be used in clinical trials in November, he said. Eventually it should be possible for those with age-related sight problems to wear the telescopic lenses all day.

The lenses are an improvement on other ways these sight problems have been tackled which has included surgery to implant a telescopic lens or wearing bulky spectacles that have telescopic lenses forming part of the main lens.

Clara Eaglen, eye health campaigns manager at the RNIB said the research looked “interesting” and praised its focus on macular degeneration.

“It is encouraging that innovative products such as these telescopic contact lenses are being developed, especially as they aim to make the most of a person’s existing vision,” she said. “”Anything that helps to maximise functioning vision is very important as this helps people with sight loss to regain some independence and get out and about again, helping to reduce isolation.”

The lenses may one day find their way into other areas as the research was being funded by Darpa, the research arm of the US military.

“They are not so concerned about macular degeneration,” he said. “They are concerned with super vision which is a much harder problem.

“That’s because the standard is much higher if you are trying to improve vision rather than helping someone whose eyesight has deteriorated,” he said.

Source: BBC

 

Most Contact Lens Wearers Don’t Follow Safety Steps

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Study: Less Than 1% Fully Compliant With Recommended Care
woman inserting contact lens

Most people who wear contact lenses say they know about the wear and care recommendations, but almost none actually comply with them, a new study shows.

More than 80% of contact lens wearers surveyed prior to an eye exam believed they followed good lens wear and care practices, but just 2% actually complied with most recommended lens hygiene steps.

And less than 1% were found to be fully compliant with recommendations such as washing their hands before handling lenses, using fresh lens solution every time instead of topping off old solution, and replacing lens cases frequently.

Contact Lens Awareness

The new survey included patients undergoing eye exams in private practice or university-affiliated optometry settings.

Overall, 85% of the patients perceived themselves as compliant with all lens-wearing practices, but only 0.4% was considered fully compliant.

The study also showed that while most of the contact wearers knew what they needed to do to avoid complications, few actually followed all the recommendations. The researchers concluded that patient awareness was not the problem.

The most frequent complications reported by the surveyed contact lens wearers were discomfort (72%) and infection (47%).

In their analysis published in the December issue of the journal Optometry and Vision Science, researchers Danielle M. Robertson, OD, PhD, and H. Dwight Cavanagh, MD, PhD, of the University of Texas Southwestern Medical Center called for new strategies to improve compliance with safe contact lens use.

Dos and Don’ts of Contact Lens Wear

American Optometric Association (AOA) spokesman Randall Fuerst, OD, says one of the most common causes of contact lens-related complications is failure to replace contacts as recommended.

“This is particularly common with lenses approved for two-week use,” he tells WebMD. “People often use them for three weeks or even a month, which can cause problems.”

When wearers use lenses longer than recommended or don’t follow proper handling and storage practices, there is a greater likelihood of deposit buildup that can lead to chronic eye redness or infection.

Wash Hands, Replace Case, Don’t Top Off

Among the other AOA recommendations:

  • Always wash and dry your hands before handling contact lenses.
  • Clean lenses often, as recommended by your eye doctor. Rub the lenses with your fingers and rinse thoroughly before soaking lenses overnight in sufficient multi-purpose solution to completely cover the lenses.
  • Use only fresh solution every time to clean and store contacts. Never top off old solution with new because the active ingredient in some solutions can break down over time. This is also why contact lens solutions should never be used after the discard date on the bottle has passed.
  • Never use tap water in any area of lens care, including rinsing the lens and lens case. Tap water may contain microorganisms that can cause eye infection.
  • Store lenses in the proper lens storage case and replace your case at least every three months. Clean the case after each use and keep it open and dry between cleaning.
  • Never swim in lenses or wear them in a hot tub.

Extended Wearers Need to ‘Listen to Their Eyes’

Fuerst also recommends that people who choose to sleep in their contact lenses use a wetting drop made for contact wearers before going to bed at night and upon waking in the morning.

Most lenses sold today are approved for a seven-day continuous use, but some newer lenses have been approved for 30-day use.

Fuerst says people who do not take their contacts out for extended periods need to be especially vigilant about “listening to their eyes.”

“If your eyes are feeling gritty, sandy, or irritated, or if they are more red than normal, take your contacts out and don’t wear them when you sleep for a while,” he says.

source:webMD