If you are just joining us in our conversation of current working theories for why myopia (near-sightedness) is becoming so much more prevalent in modern society (an increase of 66% since the 1970s!) then check out our previous articles on peripheral defocus theory and near point stress theory.  Remember all of these theories are not meant to stand alone -- our eyes develop over many years into adulthood, and in addition to genetics there are definitely strong environmental factors at play in determining the prescription we end up with.  Today we're discussing some really intriguing research that is surprisingly simple; how can light change how our eyes develop?

The average US classroom is a dim place -- set around 500 lux on average, but recommended light settings can be around 300 lux for activities like computer and projector use. image via

A glass classroom in Yangxi City, China via

Does this look like your eye? A little red, a little irritated, red rims along the lash margin?  That's the calling card of chronic inflammation caused by ocular rosacea (a type of  chronic dry eye). via

Do you have red rimmed eyes and eyelids?  Suffer from recurrent styes? Watering? Burning? Foreign body sensation? Puffy eyelids? Light sensitivity? If you answered yes to a few of these questions, chances are you have a type of inflammatory dry eye condition we refer to as ocular rosacea.  Ocular rosacea is a very common finding; studies suggest the incidence of ocular rosacea could be as high as 72% of patients with rosacea, and many of us with rosacea are undiagnosed (Chronic facial redness and flushing?  You've probably got it and just haven't been formally diagnosed!).  For years we've been treating ocular rosacea-related dry eye with lid hygiene, artificial tears, and more recently pulsing doses of oral doxycycline used to target inflammation more-so than for any antibacterial properties.  But a new study published in the International Journal of Ophthalmology last month suggests that Restasis, an anti-inflammatory eye drop used for treating dry eye, may be even more effective than our current gold standard treatment of oral doxycycline pulsed for months at a time.

The study followed 38 patients with diagnosed rosacea and ocular rosacea signs and symptoms.  The group was split evenly with 19 patients being started on Restasis eye drops taken twice daily for 3 months, and the other 19 patients being placed on 100 mg oral doxycycline taken twice daily for one month, then once daily for the two months.  All patients were instructed to use daily eyelid hygiene and artificial tears 4 times a day throughout the study period.  Before the study began and then monthly thereafter, patients were scored on symptoms (burning? watering?) and clinical signs (eyelid redness? corneal staining?) by a group of ophthalmologists.  Standard protocol dry eye testing was also performed at these visits, including OSDI surveys, Schirmer's Test and tear break up time.

Red, inflamed meibomian glands can't secrete tear film regularly as you blink,  causing dryness, burning, watering, and foreign body sensation.  That's  why a vital part of dry eye treatment includes lid hygiene and chronic use of  anti-inflammatory medications, be they topical like Restasis or oral like doxycycline.

Unless you've been actively avoiding all news media for the past few weeks, you've probably seen this report out of the Center for Disease Control: your eyes turn red in pool water not due to chlorine, but due to urine exposure.  Studies show that when chlorine interacts with urine and body waste, the ammonia and chlorine interact to form chloramine -- the chemical polymer responsible for that distinctive "pool" smell and those red, irritated eyes.  Shockingly, that's not even the worst thing the CDC found in your swimming pool!  That distinction belongs to Cryptosporidium, a chlorine resistant parasite found in human diarrhea that is the leading cause of water-born illness in the US. Studies do show that in immune deficient rhesus monkeys (and theoretically humans as well) Cryptosporidium can lead to a resilient and contagious conjunctivitis (pink eye in layman's terms).

Wearing goggles is an essential step to protect your eyes!  via

So if you are going to be in the pool this holiday weekend, what's your best way to protect your eyes from irritation and infection risk?

• Wear goggles. Goggles form a tight shield around the face that can limit ocular exposure to anything in the water.  If you need glasses to see, you can also purchase prescription goggles at most local opticals.
• Bring contact lens solution and a case.  The safest course of action is to remove your contact lenses before you get in the water.  If you do get in the water with contact lenses on, the first thing you need to do when you are done swimming is to wash your hands, remove and clean your contact lenses with a multipurpose solution.  Never rinse your lenses in tap water to clean, and rinsing them with saline will help with irritation but cannot fully clean lenses like a multipurpose cleaner can.  Do not keep wearing those lenses the rest of the day without properly cleaning the pool water away.

  If your eye looks like this, take our your contact lenses and don't put them back in until your eye returns to its' normal appearance!  via

• Consider daily disposable lenses. If you are a frequent swimmer, I highly recommend daily disposable contact lenses so that you constantly have a fresh, uncontaminated contact lens every single day.  
• Play it safe.  If your eyes are red and irritated, take your contact lenses out.  The worst thing you can do is ignore your eye when it is telling you something is wrong. Contact lenses trap irritants and parasites against the eye, preventing the eye from being able to blink these dangerous particles away as they would naturally.  If your eye feels irritated, it is a signal not to be ignored!
• Be even more vigilant about not wearing contact lenses if you are swimming in lakes! Despite the shock value of this type of news, swimming in pools treated with chlorine are so much safer than swimming in untreated lake water that is full of pathogens.  The most common blinding corneal infections associated with contact lens wear are caused by exposure to untreated lakes, or exposure to less rigorously treated hot tub or tap water.  Deanne Soza, the young gymnast we talked about in this article is an unfortunate example of how dangerous it is to wear contact lenses in hot tubs -- the residual infection nearly blinded her in both eyes and has been a major setback to her career.  Don't let yourself become the next sad story shared on social media as a warning to others.

We all know that we need sunscreen to protect our skin, but sunglasses are just as much if not more of a vital part of your battle against UV damage, cancer, and premature aging and wrinkles. Wearing sunglasses is one of the only ways you can help reduce your risk of blinding conditions like ocular tumors, cataracts, and macular degeneration.  Not to mention the fact that they are best way to protect your delicate eyelid skin from wrinkles and common skin cancers.  And the best thing about sunglasses?  Well they are fashionable of course too.  Just check out some of my favorites from Instagram:

Keratoconus causes progressive corneal steepening and is devastating to vision via

For patients diagnosed with keratoconus, accepting how little can be done with modern medicine to protect and preserve their quickly declining vision can be the most devastating part of the diagnosis. Our current treatment model in the world of keratoconus goes something like this: try to keep going in contact lenses as long as possible, and when even those can't do the job anymore, time for a corneal transplant. Many patients live with a possible visual doomsday hanging over their head -- that day where contact lenses just won't work anymore and they might have to accept that they are going blind or needing major, risky surgery. Luckily, new technologies are being researched and explored that can stabilize the cornea and help prevent further vision loss.  Both corneal Intacs and corneal cross linking are currently performed in the United States, and both can help stabilize the degenerative process behind keratoconus. Unfortunately, not everyone is a candidate for these surgeries.  Advanced keratoconus patients whose corneal curvature is steeper than 60D or whose cornea is thinner than 350 microns wouldn't be able to pursue either of these surgical options due to the risk of complications.  But new research by Dr. Gerrit Melles in the Netherlands and Dr. Jack Parker with UAB has demonstrated a possible intervention that would stabilize the corneas of even these higher risk patients: Bowman's layer transplantation.

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If you are a fan of unique, fashion forward, finely crafted eyewear, then meet your new favorite independent designer.  Darylynn Eyewear has been wowing the optical world with their innovative designs that often take retro-inspired looks and push them forward into modern works of art. Founded by Darylynn Ayala Maculoso and her husband, Joseph, this duo's optical creations are a favorite on social media too -- just check out their instagram account to see why.  Their latest campaign showcases the boundary-breaking style we've come to expect as a Darylynn signature, making retro shapes like the oft-used cat eye frame feel fresh and new.   From the designer: "Darylynn Eyewear was created on the notion of making people feel "Glamorous" in their Italian hand crafted, high quality frames. We are in the mind set of creating Get-Noticed eyewear for glamor junkies everywhere."

Model wearing Giuseppe in black

Model wearing Stunning Stacy in black

We're exploring the most talked about theory of why near sighted people keep getting more and more near sighted throughout childhood today -- Peripheral Defocus theory.  If you want to read about other theories, check out the first post in this series discussing the Nearpoint Stress model.  Keep in mind that none of these theories purports to stand alone -- we know that genetics plays a large role in why we become near sighted, but because the rates of myopia are increasing so rapidly worldwide (the US alone has seen an increase of myopia of 66% since the 1970s), there has to be environmental factors at work too.

The Basics:

Let's start from the true basics of what's going on in the eye, because if you try to read scientific journal articles about peripheral defocus it can get complicated really quickly.  The key to understanding this theory is to have a god idea of how light focuses on the retinal photoreceptors in the back of the eye.  Light enters through the pupil, is refracted by the lens, and is focused onto the retina to send a clear image to the brain.  In emmetropes (people with "perfect" eyes or no prescription) light from a distant object will fall perfectly onto the retina without any need for the eye muscles to work and reshape the lens to change the eye's focus.  In hyperopes (farsighted people), light would actually focus behind the retina, but the eye muscles move to reshape the lens to bring light onto the retina and into clear focus. That's why farsighted people tend to see very well in the distance unless they have a really high or unequal prescription -- their eye muscles are strong enough to bring things into focus and clear the world around them without any additional help. This muscle and lens action to bring light into focus on the retina is called accommodation.  In myopes (near sighted people), light focuses in front of the retina.  Accommodation can't shift this image backwards, so near sighted people can't see clearly at a distance no matter what they do.

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