Many conditions of the eye that are considered a normal part of aging  can be helped by a healthy diet and by supplementation of nutrients.  Two of the most important are lutein and zeaxanthin.

23 million people worldwide have age-related macular degeneration  (AMD) or cataracts.  Macular degeneration is the leading cause of blindness of people over 55 and the incidence is supposed to triple by 2025.  (Diabetes is the leading cause of blindness up to that point).  Studies show that a good diet  is essential for good vision and to reduce the risk of eye diseases.  We know that antioxidant vitamins and minerals reduce the risk of AMD by 25%.

Lutein and Zeaxanthin are nutrients that are naturally found together in green leafy vegetables such as spinach and kale and in bright orange/yellow vegetables like corn and orange peppers. Carrots have beta-carotene which is also an important nutrient to enable the rods and cones to work properly.

Lutein is a major photopigment that is deposited in the macula of the eye.  It protects the macula by absorbing damaging UV radiation and also serving as an antioxidant.

Zeaxanthin is also an antioxidant and a photoprotectant.  Low levels of zeaxanthin are associated with an increased risk of AMD.  Because it is found in low levels in the normal diet it almost always needs to supplemented.  Zeaxanthin is deposited in the very center of the macula, the fovea -  the part of the eye most sensitive to sharp vision.

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What does  art teach us about vision?

“Art is a lie that enables us to realize the truth”  Pablo Picasso 1923

Picasso encouraged the viewers of his art to make an effort to understand the human condition through his interpretation of reality as expressed revealed in his art. What is true about art as it relates to vision? We are moved by art in our own personal way and know that it speaks to us on a deeper level – a triumph of the ascetic over the mundane.

Eye doctors have long been intrigued by artists, especially concerning how their art has been affected by visual maladies.  How did their vision affect the way they portrayed the world? Great artists must possess many gifts – manual dexterity, creativity – but none is more essential to their enterprise than the gift of vision.  We often speak figuratively of the artists “vision” and its effect upon their work, perhaps forgetting that their vision is literally of utmost importance.

We know that El Greco apparently had astigmatism and that Monet’s work changed as he was progressively affected by cataracts.  Edward Degas, Edvard Degas,  Georgia O’Keefe and Mary Cassat suffered from a loss of vision and had to deal with it. Even though eye defects and disease can clearly explain some features of art, it is equally obvious that most artistic gift is independent of ocular perfection.  Having 20/20 vision does not make one an accomplished artist and the lack of such vision does not preclude one from artistic greatness.

In subsequent posts I will explore in more detail the connection between art and vision.

www.littlefieldoptometry.com

The phone rang and she told us her story.  She had been using a little metal comb to do something to her eyelashes – don’t ask me what, but you women out there might know-  and she accidentally scraped her eye.  Could she come in right away and have me take a look and stop it from hurting?  Of course, Lavon the receptionist said, and a short time later Susan (not her real name) came in the office for me to see.

We took a look at the little metal comb she was using – to me it looked like a medieval torture instrument – and I thought, NO WAY would I ever get anything like that close to MY eye.  Anyway, I took a look at her eye with the slit lamp bio-microscope that we eye doctors use to examine the eye and saw that she indeed had scraped the cornea of her eye.

I took a picture of her eye with the scrape on it and kidded her that it looked like a salamander.  I wouldn’t have been in a kidding mood if I thought the eye was permanently damaged, but I knew that the cornea is one tough little membrane that protects the eye with military efficiency.  It is only 1/50^th of an inch thick, but is composed of 5 distinct layers.  The outer layer is the epithelium and it is only 1/500^th of an inch thick.  It is on top of the next layer which is even thinner that is called Bowman’s membrane.  Bowman’s membrane is very tough and resists penetrations by most foreign bodies – but not needles, knives,  bullets or mascara instruments of dubious safety!

Corneal Abrasion

Susan had scraped her epithelium and I knew that if I put an antibiotic and a bandage lens on the cornea it would feel better right away and heal up quickly.  Sure enough, when she came back for her visit the next day, to make sure all had gone well, she was almost completely healed.

The epithelium is a very important layer of the cornea.  We now know that “dry eye” – which causes symptoms of dry, irritated, scratchy, uncomfortable eyes and also causes unstable vision- is actually a disease of the ocular surface, which includes the epithelium, conjunctiva, lacrimal and meibomian glands.   Fortunately, our ability to treat these problems has EXPLODED in just the last couple of years.  It’s not just about moisturizing drops anymore!  More, much more, later.

Dr. David Littlefield

www.littlefieldoptometry.com

Prevalence of Myopia

Myopia is becoming more prevalent – some might even say it has become an epidemic.  Myopia (nearsightedness) has increased in the US population by 66% in the last 30 years. The World Health Organization has categorized myopia and uncorrected refractive error with cataract, macular degeneration, infectious disease and vitamin A deficiency as among the leading causes of blindness and vision impairment in the world. Myopia can be classified into two groups – low and high.  The low group is up to -6.00 diopters in correction and the high (or pathological) group greater than -6.00.  The pathological group has a much higher incidence of potentially blinding conditions including macular degeneration, retinal detachment, glaucoma, loss of visual acuity and color sensitivity.  The prevalence of myopia varies by ethnic group reaching as high as 70-90% in Singapore. In Japan it is estimated that over a million people suffer from a vision impairment associated with high myopia that cannot be adequately corrected with glasses or contact lenses. The prevalence of pathological myopia in some population based studies is as high as 3% of the population.  In addition to the visually disabling effects are the economic costs – not only for the treatment costs but also for the loss of income due to visual disability. Since no universally accepted treatments have been able to reverse the structural changes of pathological myopia (the lengthening of the eyeball and thinning of the retina) it has long been the goal of research scientists in vision and ophthalmologists and optometrists to understand the factors that lead to these devastating changes in the structure of the eyeball and to devise therapeutic strategies. The common solution of wearing glasses or contact lenses is temporary as most children will get worse each year, resulting in more blur and thicker lenses.

Although most researchers agree that there is a genetic component to the development of myopia there is a growing amount of research pointing the finger at visual experiences early in life that affect eyeball growth and the subsequent development of myopia. Studies with animals (chickens, tree shrews and others) show that early visual experience affects the growth of the eye and the eventual myopia that may result. Specifically, the mismatch between the focus of central and peripheral vision can induce myopia. A typical eyeglass or contact lens that corrects myopia for the central focus will overcorrect the peripheral focus. This causes myopia to increase. Certain medications have a biochemical effect that will slow down the progression of myopia, but they typically have undesirable side effects. The newest research shows that specially designed bifocal contact lenses can slow down or even stop the progression of myopia.  The most exciting studies show that orthokeratology can stop and even reverse (during the treatment period) the myopia that has already occurred, but only up to a certain amount, typically -6.00 diopters.

Ways of Controlling Myopia

Orthokeratology is vision correction without surgery.  Orthokeratology, is also known as corneal refractive therapy (CRT), vision shaping treatment (VST), corneal molding or Ortho-K .  It is the gentle reshaping of the cornea to correct myopia (nearsightedness).  The cornea is the eye’s equivalent of a watch crystal. It is a clear, dome shaped structure that overlies the colored iris. Its tissue is very thin (about 1/50^th of an inch) and very pliable. Because the cornea separates the eye from air and the outside world and because it has a curvature that bends light towards the back of the eye, it is responsible for 2/3^rd of the eye’s corrective power and contributes to various conditions such as nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. We can compensate for the eye’s focus defects by reshaping the cornea.

It has been practiced for over 40 years.  In the early years a series of lenses were fit on the eye, each with a progressively flatter fit, with the goal of reshaping the curvature of the eye. The techniques and success have greatly improved over the last 10 years.  Now orthokeratology is accomplished by using specially designed contact lenses called reverse geometry lenses that gently flatten the cornea by pushing the central epithelial layers directly over the pupil towards the periphery of the cornea.  This movement of corneal cells causes the center of the cornea to be thinner and flatter thus focusing the light closer to the retina. Orthokeratology refocuses the images on the retina in the same way as LASIK, but reversibly. Orthokeratology is FDA approved and FDA certified training is required of eye doctors to fit overnight ortho-K lenses. Only a handful of orthokeratology lenses have been approved for overnight orthokeratology by the FDA.  A commonly used approved lens is the Paragon CRT (Corneal Refractive Therapy) Lens.

Corneal Molding has evolved into a method where many patients achieve success with the first lens.  Good results typically take less than a week.  The process is accomplished while you sleep using a computer designed reverse geometry contact lens.  The lenses are inserted at bedtime and removed in the morning.  The lenses, also known as vision retainers, safely and gently reshape the cornea changing the eye’s focus.  Most patients will have good vision throughout the day.  Some patients may only need to wear their lenses on alternate nights to maintain good vision. Ortho-K can produce results in a surprisingly short period of time. The length of treatment to achieve your goals can vary from patient to patient. Factors which can affect the speed of treatment include your initial degree of myopia, the rigidity of your cornea, the exact topography (shape) of your cornea, your tear quality and your expectations.  Children are especially good candidates because their corneas are more pliable.

Patients interested in orthokeratology start with an eye exam and a free orthokeratology screening.  After a comprehensive eye exam, including an orthokeratology consultation, corneal topography is done.  These are topographical maps of the cornea. Everyone’s topographical map is different, much like our fingerprints. Corneal topography shows irregularities in the cornea and is essential to designing contact lenses that will mold your cornea.  Corneal topography also allows us to diagnose corneal diseases such as keratoconus. Specular microscopy is also performed which allows us to see that the endothelial corneal cells are healthy.

Dr. David Littlefield

www.littlefieldoptometry.com

Joanne was worried.  Her daughter Rachel first started wearing glasses two years ago when she was in third grade and then last year they needed to be made stronger.  Now, on this visit to the optometrist, she was told that Rachel needed an even stronger prescription.

She expressed her concern to the optometrist and was assured that this was normal and she shouldn’t worry.  “She won’t go blind, but she just will probably need to have stronger glasses every year or so for some time to come.  Often times eyes our eyes don’t stop changing until we stop growing and reach our early twenties.”

The average increase in myopia is about -.50 dioptors of change a year. Over the years many attempts have been made to prevent this from happening, but nothing has been particularly successful.

The statistics of myopia are truly frightening.   All over the world myopia is getting worse.  Myopia has increased by 67% in the US over the past 30 years and now more than 40% of individuals from 8 to 54 are myopic.  In Singapore 80% of high school children are myopic.  It is a true epidemic – over a billion people in the world are affected by myopia.

Exciting new research tells us for the first time what causes myopia and we are now beginning to figure out ways of slowing it down and even  preventing it. But the treatment works best when it is started at the earliest stages of myopia.

Myopia can be thought of as the eyeball being too long for its focus.  When light focuses in front of the retina instead of on the retina the image is fuzzy. Spectacle and contact lenses shift the focus back to where it belongs, which restores the sharpness of the image.

But how does the image, in normal individuals, ever stay focused where it belongs as the child’s eyes grow?  Research shows that the eye has the means to adjust itself to the proper focus.  This process is called emmetropization, and it occurs when there is a proper focus in the peripheral retina.  That is, it only works well when the peripheral (off center) focus is not “over-focused”.

Unfortunately, in many individuals, when the central “on-center” image is focused clearly (as when looking at the eye chart) the peripheral focus is “over-corrected”; the periphery of the correcting lens is too strong. We now know that this causes an increase in the myopia.

Traditional glasses and contact lenses have the same focus over the entire lens.  Bifocal glasses have a different focus at the bottom of the lens for reading, but only at the bottom.

There are special multifocal contact lenses that have the proper less strong focus 360 degrees around the lens. A recent study of 122 children showed that these lenses slowed the increase in myopia from -.50 diopters  per year to -.03 diopters, an insignificant increase. But even though these lenses can slow down or even stop the increase in myopia, they cannot reverse a myopia that has already occurred.

An exciting recent technology is orthokeratology –  utilizing special eye molds to reshape the eye to the proper focus.  You sleep with them and remove them during the day. There are some limits to the amount of correction that can be achieved, so it is best to start the treatment program before the myopia becomes too advanced.

Dr. David Littlefield

Myopia Prevention

If there is still anyone on Planet Earth that hasn’t heard of the connection between smoking and heart disease and lung cancer they must live in Mongolia or at some desolate outpost far removed from civilization.  But everyone has not yet quit smoking. Smoking has decreased significantly over the past 20 years but has plateaued over the last 5.

But most people do not realize there is also a correlation between smoking and eye disease.  People who have 40 pack years of smoking (one pack a day for 40 years or 2 packs for 20 years) have 2.75 times the risk of wet macular degeneration and also an increased risk for cataracts and diabetic eye disease.

Smoking and diabetes are an especially poor combination because diabetes affects blood vessels preventing proper blood flow to every part of the body. Over time the lining of the blood vessels are damaged and they become coated with plaque.

The good news is that after as little as 10 years, and certainly after 20, the effects of smoking can be erased from the body’s tissues. It is difficult to show a person the effects of smoking on their lungs or their heart, but optometrists and ophthalmologists have the technology to show a person the effects of smoking on their eyes.  Retinal photographs shows damage to the macula and OCT images show the damage on an even more microscopic level.

Aside from quiting smoking, there are also nutritional supplements (antioxidants)  that can help overcome some of the damage done by smoking.

Dr. David Littlefield

www.littlefieldoptometry.com