Farsighted Eyes Contact lenses And Other Ways Your Optometrist Can Improve Your Look With a Thinner, Lighter Lens Designs and Eliminate the Bug Eye Look! Read On-

First a disclaimer-you have to read to the end for contact lens solutions for farsightedness. Being farsighted (hyperopia is the technical term) is when distance vision is good, but close reading text is hard to see. It is a somewhat confusing term since farsightedness is actually an optical error of the distance vision. If your optometrist finds your eye prescription is extremely farsighted, you can’t see up close or far away. Fortunately a muscle referred to as the ciliary muscle surrounds the lens in the eye, and is attached to the lens with small fibers called the zonular fibers. Active contraction of this muscle loosens the tension and increases the eyes focusing power. In lower amounts of farsightedness under the age of 40 the focusing capacity of the eye can accommodate for farsightedness and clear your vision for both distance and near easily.

Farsighted Eye Problems Optometrists Find You May Be Experiencing Needlessly

Even lower amounts hyperopia have been shown to interfere with reading in some children, but between 2 to 3 diopters it usually starts to create symptoms in most people. Kids and teens have an enormous amount of accommodation, and sometimes very large prescriptions for farsightedness are not noticed because they can clear near and distance vision by focusing. Often they will suffer headaches and an unconscious aversion to reading because of the eyestrain and effort constantly being required to keep their vision clear. As we grow older we gradually lose the ability to focus. This degradation of focusing starts between the age of 15-20 but effects distances so close that we never notice because we don’t use our vision at that location. People who are farsighted have a different type of problem that individuals who are nearsighted. They constantly have to focus to keep their distance vision clear and as objects move closer they have to ramp up their focusing efforts. This is not a problem if they are young and have lower amounts of hyperopia, but as they age or with larger amounts of hyperopia the extra effort they are exerting starts to be noticeable. This occurs with reading and computer use initially, due to the added effort of focusing on top of the amount required for distance. In Fort Collins we have a higher use of computers and more symptoms from farsightedness are being seen by optometrists. Frequently, eye patients will be prescribed glasses or contact lenses for close work that only correct the distance amount of farsightedness. This lessens the amount of focusing needed for near back to normal levels that rarely create visual discomfort. As farsighted optometric patients enter their early 40′s they find they have gradually started wearing glasses all the time. Many people mistakenly believe that wearing the glasses have made their eyes weaker, and sometimes feel their eye doctor has made them dependent on the lenses. This is an incorrect assumption, as the loss of accommodating ability would have occurred without wearing glasses, and would have been a problem at an earlier age in the absence of corrective eyewear.

New Eyeglasses Lens Technology For Farsighted Vision

Optically, the farsighted eye is usually too short and light focuses behind it instead of on the retina for distance. There may also be individual components of the eye that are too weak to focus vision adequately. The lens could be a little short in power, or the clear cornea tissue on the front of the eye could be curved slightly less than normal. A lens with plus, or positive power is used to correct for hyperopia. This is a lens thicker in the middle and thinner on the edges, like a biconvex lens. Best optical design for clear central and peripheral vision is a lens more curved on the front and still curved forward on the back, just to a lesser degree. This results in a lens with a center that sits relatively far away from the front of the eye. As you move an ophthalmic lens used for farsightedness away from the eye, the eye appears larger, just like the effect produced from moving a magnifier away from an object. This also magnifies the size of the image seen by the eye. Advanced optical designs have eliminated the resulting type of coke bottle appearance by using aspheric lens designs. Aspheric lenses start out with a front lens surface spherical in the center (like the curve on a tennis ball) then the curvature gradually decreases or flattens towards the edge of the lens. This is the traditional design that has a spherical curvature on the back surface of the lens. Newly emerging freeform lens technology allows aspheric lens curves to be ground on the back surface of a lens that steepens away from the center in an atoric design. Atoric designs use different degrees of asphericity in different tangential lines to compensate for astigmatism in your prescription. Either way, the flattened lens design allows the lens to sit closer to your eye decreasing the magnification or bug eye effect. The aspheric design by the complex quirks of optics also counters several forms of optical aberrations (blurring of vision) that normally occur when you look to the side of a spherical lens using a flatter lens design. A common misconception is that aspheric lenses improve vision. They do not significantly improve vision but they do allow for a thinner, lighter, more cosmetically appealing lens with less magnification. The aspheric design allows these improvements to be achieved while maintaining clear peripheral vision. The lenses available to your eye doc do just keep getting better, and much more so the last 5 years in many different ways.

Farsighted Eye Facts From Your Optometrist to Consider When You Have Insomnia

1. Some people are farsighted in one eye and nearsighted in the other. If the amounts are just right they can see near and distance without bifocals
2. President James Buchannan was farsighted in one eye and nearsighted in the other (and had an eye twitch)
3. President Harry Truman was farsighted
4. Latent farsightedness occurs when a child has compensated by sustained focusing for distance for so long they cannot relax their eyes for a true reading of the prescription. Only checking the eyeglass prescription after eye drops have eliminated the eyes focusing capacity can yield an accurate prescription reading
5. Ohio State University has started a study to see if providing prescriptions that are not strong enough for extremely farsightedness infants will help the eye self correct themselves
6. The eyes tend to become slightly more farsighted (or less nearsighted between the age of 40 to 50)
7. Young to middle age males can develop fluid swelling in the central retina and become farsighted as a result of stress
8. Children that are farsighted tend to have brothers and sisters that are farsighted
9. Approximately one in four people are farsighted

Vision screenings have value in detecting problems, but often miss farsightedness because of children’s capacity to focus and pass the 20/20 test. Only a thorough eye exam by your eye doctor can assure you your children and teens have the correct eye prescription for efficient reading and learning in school. Schedule them for an annual eye check up today.

Now For The Contact Lens Part

It is very simple.

1. Contact lenses sit right on top of your eye and therefore supply very little magnification effect
2. Contact lenses stay centered in front of your eye s you look to the sides-we don’t have to worry about aspheric lens designs from an optical aberrations perspective. (They may be used for thinner edges and improved comfort in some cases though)
3. Contact lenses used to correct Hyperopia (farsighted) are significantly thicker in the center and effectively provide a much greater barrier to oxygen passing through to keep the cornea eye tissue healthy underneath. Silicone Hydrogel contact lens materials have almost completely eliminated this barrier for farsighted contact lens wear

All of these reasons make contact lenses frequently the primary choice for correction of higher amounts of farsightedness in kids and teenagers when their appearance is so important to their self esteem. Who doesn’t want to look better, especially when the old alternative were bug eye magnifying lenses that weighed a ton and slipped down your nose constantly, making you an imitation of Clark Kent, always pushing those things back up. Remember, it does not have to be that way today with glasses or contact lenses.

Optometrists Find High Incidence of Eye Growths and Bumps on White of Eyes in Northern Colorado are Benign & Often Pinguecula

A large number of people in the Fort Collins show up at the optometrists office with benign growths on the white part of their eye referred to as pingueculas. Actually they develop on the conjunctiva, the clear tissue that covers the white part of the eye (the sclera). Often they appear as mildly elevated yellowish bumps, visible to the patient or a family member with a urgent rush to the eye doctor. Often people are reluctant to discuss their concerns hoping it will be found during an eye exam. You should not hesitate to mention this at the beginning of you visit to the optometrists office. Because they are so common, you eye doctor may not mention the presence of a pinguecula on your eye unless you ask. While most optometrists find pingueculas developing in patients eyes who are over the age of 40, it is becoming more common to see them by the mid twenties. They are presumed to be caused by a UV radiation from the sun and low level irritants like dust and small particles in the wind. The incidence increases closer to the equator. Fort Collins East of I-25 they are extremely common due to the farming industry with people spending larger amounts of time outdoors and in dusty environments. People who spend their leisure time on motorcycles are also more at risk due to the ultraviolet exposure and particles from the blowing wind.

What Causes Eye Growths of Pingucula

Just as skin loses is capacity to stretch with age, so does the conjunctival tissue when it is exposed to sunlight and irritation over a cumulative period of years. In Northern Colorado people frequently visit doctors for skin changes that are essentially occurring from the the same as the eye conjuntival changes.

Eye Doctors have found the elastosis, or the capacity of the tissue to smoothly stretch and return to normal is compromised from changes to the conjunctival tissue. Collagen forms the framework, but elastin protein fibers around the collagen fibers provide the stretching capacity. The UV radiation in Fort Collins is higher due to the altitude, reflections from snow, and the amount of time we spend outdoors. With close to 300 days a year of sunshine the UV exposure is higher than most areas at a similar latitude. Altitude increases the UV dosage by 4-5% /1000 feet of elevation gain. Compared to sea level this adds approximately 25% above sea level exposures.

First there is an accumulation of abnormal cells that are altered elastin and / or collagen.  Eventually the area starts to lose cells and becomes more of a deposit of protein materials often referred to as hyaline deposits. Calcification can occur over time also. Several theories have been proposed by eye research clinics for the changes seen in the tissues that form the pinguecula.  This UV radiation and low level chronic irritation causes changes that may be:

1. An increase in the production of elastin fibers by the fibroblast cells and changes to the elastin nature into a more twisted form as they replace some of the collagen fibers. This may induce degenerative changes to the collagen fibers.
2. A interference with the natural cycle of cell programmed cell death of elastin resulting in an overproduction that takes on the abnormalities.
3. A degradation of the collagen fibers into a compromised form resembling elastin.
4. A combination of the above

Other factors may make the conjunctival tissue more susceptible to forming pinguecula.

1. Since the conjunctiva tissue does not have the tough keratin layer like the skin it is damaged faster by UV radiation.
2. The clear conjunctiva tissue is also transparent and the solar radiation that is not absorbed passes through to the sclera. We know from science that color of the surface being irradiated has a large bearing on the amount of back reflected radiation including UV.[1]   It is a very thin tissue, and the white scleral tissue underneath it with it’s white coloration should have an albedo in the range of 80-90% similar to the reflectance of snow. Measured animal studies of conjunctival tissue reflectivity across the 440 to 1000+nm range shows a steady reflectance of above 40%. Somewhere between 40 to 80 percent of the UV radiation is being added to the initial dose as it passes through. This extra back reflection of UV into the conjunctiva tissue also increases the exposure and ages the tissue faster than skin.
3. Eye conditions that increase the size of the fissure, or how wide your eye stays open, also will increase the incidence of pinguecula. Thyroid eye disease and eyes that are not as deeply recessed (the beady eyed individual with a protruding eyebrow to shadow the eye) or more likely to develop pinguecula. Studies have shown an increase in pinguecula in patients with Thyroid Orbitopathy (hyperthyroid or an overactive thyroid gland that effects the eye) that is only significant with the widened eye fissure or amount of the eye normally exposed when open). Increased dry eyes was not correlated further suggesting UV exposure as a causative factor. [5]
4. The nose acts to reflect more light onto the eye somewhat like a dull mirror, and pinguecula are more commonly found on the white side closest to the eyes, but they are also found on the temporal side.
5. The deeper, or basal layers of the superior nasal conjunctival tissue contain more dendritic cells. Dendritic cells are a type of antigen-presenting cell (APC). Antigens are molecules or molecular fragments that bind to a site on on the surface of cells, and except for autoimmune diseases they are the molecules from outside the body. Dendritic cells present them to the T helper cells that increase the immune response and that cause an increase in inflammatory cells. The tears flow towards the nose by slight eyelid horizontal movements that accompany each blink. This ensures a continuous flushing of debris and antigens from the tear film, Since the tears flow in this direction logically their would be more dendritic cells to help remove the excess antigens. Due to the density of the dendritic cells and the propensity to create more inflammation, it has been postulated this may increase the overall likelihood of pinguecula forming in the nasal region.
6. Psoralen plus ultraviolet A (PUVA) treatment has been used widely in the past for various dermatoligic conditions. It has seen a reduction in use due to other methods. PUVA uses a photosensitizing agent (8-methoxypsoralen, Oxsoralen®) taken orally or applied to the effected area before exposure to ultraviolet A  light (320-400 nm).  At least one case of pinguecula associated with PUVA has been reported. (the patient was in poor in compliance with eye protection)

Pinguecula Are Always Benign Growths

Once a Pingueclua has been properly diagnosed by your optometrist you can rest assured. Pinguecula are always benign growths and never develop into any form of eye cancer. They can start to grow across the clear cornea tissue on the front of the eye at which point they are referred to as pterygium. Pterygium need to be followed as they need to be removed by an eye surgeon if they approach to close to the line of sight. While the surgical removal is fairly simple, they tend to recur and leave a scar. That leaves a wait and follow choice by your eye doctor. Because they are so slow to develop it is fairly easy to manage. New technology is reducing the recurrence, but remember, the majority of pingueculas don’t develop into pterygiums. In our Fort Collins Eye Clinic we occasionally see patients with symptoms related to pinguecula.

Pinguecula Symptoms and Signs

The elevation may disrupt the normal tear resurfacing on the eye and create an area of dryness and discomfort. It can also result in the edges of soft contact lenses settling poorly on the eye and leaving a gap between the soft contact lens and the conjunctiva. This often results in the lens drying out and the peripheral contact lens edge curling away from the conjunctiva.  Contact lens patients will blink and subsequently the eyelid movement can eject the contact lens. Rigid gas permeable lenses may leave a gap over the conjunctiva and edges of the cornea that dies out and damages the peripheral cornea epithelium surface cells and the conjunctival cells. The edge of the gas permeable lens may also irritate the pinguecula and result in a chronic red eye when contact lenses are worn. This can often be resolved by changing the diameter or size of the gas permeable contact lens.   A test used in research facilities called “tear ferning” evaluates the mucous layer of tears by allowing a  sample to dry on a slide and crystallize. This is often abnormal around pinguecula indicating a mucous irregularity inducing dry eyes. Occasionally pinguecula become inflamed and need prescription eyedrops to restore comfort. The incidence of problems is low and treatable so eye doctors almost never remove a pinguecula.

Optometrists Prevetative Steps For Pinguecula

UV prescription eyeglasses (or non prescription quality sunwear) is the most important preventive step you can take.  Not only will it help prevent pinguecula, but also a number of other eye diseases associated with sunlight exposure. Do a favor for your children and teenagers eye health, start them in prescription sunglasses (transition lenses that lighten and darken also offer UV protection). When you think of sunscreen think of sunscreen for the eyes. The more time you spend in the sun, the more you should think of sunwear that wraps around your face and protects the sides. Up to 40% of the UV exposure can still enter from the unprotected side of a normal pair of eye glasses. Special motorcycle eyeglass frames have become very popular in our Ft Collins Eye Care Center due to the side protection from UV and wind & dust. Wearing a hat with a brow helps reduce UV exposure. Limiting midday sun exposure is very useful when possible. The morning and afternoon sun is lower on the horizon and has a much longer path to travel through the atmosphere which filters out more UV. Don’t avoid the sun totally. While there is much controversy at this point, it does appear that some sun exposure is good for your health, reducing some forms of cancer and possibly decreasing the incidence of multiple sclerosis. While vitamin D may be the protective factor some studies indicate their may be other factors and biochemical involved.  Keep your eyes posted for more eye updates as we learn more about the fascinating world of vision!

References

[1] http://geography.about.com/od/physicalgeography/a/solarradiation.htm

[2} http://www3.interscience.wiley.com/journal/112130369/abstract?CRETRY=1&SRETRY=0

[3] Hoang-Xuan,Thanh;  Baudouin, Christophe     Inflammatory Diseases of the Conjunctiva,  Catherine Creuzot-Garcher

[4] Journal of the American Academy of Dermatology
Volume 57, Issue 1, Pages 177-178 (July 2007)
Pinguecula following psoralen and ultraviolet A therapy
Amit Garg, Michael Loosemore, BAb

[5] Cornea:
June 2010 – Volume 29 – Issue 6 – pp 659-663
doi: 10.1097/ICO.0b013e3181c296ab
Clinical Science
Prevalence of Pinguecula and Pterygium in Patients With Thyroid Orbitopathy
Ozer, Pnar Altiaylik MD; Altiparmak, Ugur E MD; Yalniz, Zuleyha MD; Kasim, Remzi MD; Duman, Sunay MD

Keratoconus | Eye Doctors Contact Lenses and New Options for Treatment

Keratoconus is an eye disease that causes vision to gradually worsen over time, as the transparent corneal tissue that covers the front of the eye thins and bulges forward, forming the cone shape that keratoconus is named for. Rapid increases in nearsightedness and astigmatism are common with frequent changes in your eyeglass prescription. Scarring of the cornea can also occur resulting in significant vision loss.

Keratoconus Symptoms Your Optometrist may discuss

• The appearance of long linear light streaks in your eyesight at night

• Visual Glare and halos around lights, especially car headlights and taillights at night

• Double Vision

• Distorted Vision

• Blurry Vision making it difficult to read

• Ghost like eye images of white light surrounding objects you are viewing, sometimes noticed as multiple dots when viewing on small light image-can be seen with one eye

• Eye Sensitivity to light

• Eye Doctors Agree Keratoconus usually show up most commonly between the teenage years of 16 up to age 30

When this corneal eye disease manifests at earlier ages optometrists often find a more aggressive form with ongoing, frequent changes in your eyeglass or contact lens prescription. The best guess is the occurrence rate is about 1 in 2000 people. It is hard for eye doctors to pin down the exact rate of this eye disease because it can be very mild and remain undiagnosed, especially when it burns out early (form fruste), or stops progressing after several years. Corneal Keratoconus creates irregular astigmatism, causing curvatures on the cornea tissue that are not nice smooth curves. Instead the eye curvature resembles the surface of a potato with dips and valleys on a very irregular shape. This type of shape makes it very difficult for your optometrist to prescribe an eye prescription for eyeglasses that results in clear vision. The lenses would have to be made in very strange shapes to result in clear vision. Even lenses that have been designed in this manner are rendered ineffective the moment your eyes look off the center of the lens. Irregular astigmatism also occurs without kerataconus, but it does not tend to progress and result in the characteristic steepening of the cornea resembling a cone shaped area. Usually kerataconus presents in one eye and over time well over half of the eye patients will have both eyes involved.

The cause of Kerataconus and the changes in the cornea are surprisingly not well known by the optometric research clinics at this time. In the past, much speculation centered around eye rubbing and ocular allergies. Some eye physicians have speculated that Keratoconus is triggered by eye rubbing that starts an inflammatory cascade in the cornea. Frequent eye rubbing also could cause mechanical tissue breakdown in areas of the cornea that are already compromised. Research by eye doctors has shown between 6-8% of patients with kerataconus have a family history, indicating there is a genetic component in some cases. Several areas of chromosomes have been identified as potential genetic markers and are being investigated further. Also, certain eye diseases such as retinitis pigmentosa, retinopathy of prematurely (damage to the retina tissue in the back of the eye from premature birth), Leber’s congenital amaurosis (a degenerative disease of the optic nerve), and vernal keratoconjunctivitis (a type of allergic eye disease which creates itchy eyes and frequent) appear to have some correlation. Some disease of the body also have a degree of co-occurrence with Keratoconus- Ehlers-Danlos syndrome, Down syndrome, osteogenesis imperfecta, pseuodoxanthoma elasticum), mitral valve prolapse in the heart, Laurence-Moon-Biedl syndrome, Rieger’s syndrome and neurofibromatosis. Several of these diseases interfere with normal collagen development and may precipitate kerataconus by disrupting collagen development in the cornea.

The changes to the cornea from Keratoconus are mostly unknown. The cornea consists of 5 layers and is about 1/2 mm thick (550 microns or about the width of 5 human hairs). The epithelium layer is the surface layers of cells. Underneath the eyes epithelium layers is a thin basement membrane sitting on the anterior limiting membrane, also know as bowman’s membrane. The bulk of the corneal thickness is in the stromal layer, where the collagen protein fibers run across the cornea, adding the tensile strength. Tensile strength is the degree a material can be stressed and still return to it’s original state and shape. Collagen is the memory material of the cornea. The structure of collagen changes in the center area of the cornea with shorter fibers, that cross more, run at different angles, run though each other, form connections to Bowmans membrane, and also form connections originating from Bowman’s membrane. It has been suggested from research by Jan P.G. Bergmanson, OD, PhD, PhD h.c, DSc, & Jessica H. Mathew, OD that this alteration in structure near the central cornea may help explain the nature of Keratoconus in the future, With shorter fibers running in differing directions with various connections the central cornea would seem to be more prone to breakdown of the normal collagen structure. Optometrists have found the bulging cone area characteristic of Keratoconus cones usually form close to the central cornea, slightly inferior, which seems to substantiate the altered central corneal tissues may play a part in the eye condition. Early changes may occur in the surface epithelial cells disrupting the basement membrane. When keratoconus begins, whatever the cause may be, enzymes increase and start damaging the epithelial basement membrane. This is the membrane formed underneath the lowest level of epithelial cells. Subsequent breaks in the corneal anterior limiting membrane occur and the cornea starts to thin centrally, probably due to the susceptibility of the different surface anatomy of the collagen fibers under lying Bowman’s membrane. As these breaks occur the surface epithelial cells can contact the stromal level of the cornea where most of the structural framework of this eye tissue is located. Small proteins called cytokines are released and alter the fluids around the cells, leading to scarring of the cornea.  Stromal fibers may move through the anterior limiting membrane. Whatever the cause, a disruption of the normal collagen structure causes the memory shape to lose its capacity and irregular shaped corneas to subsequently develop. There are indications of changes in the different enzymes that degrade proteins and induce changes in the collagen and the spaces surrounding the cells in the cornea. Cathepsins are one type of protein that increase as kerataconus starts to occur. These could lead to destruction of the so called extra cellular matrix, the substances surrounding the cells and lead to degenerative effects in the cornea.
They may also indirectly cause a reduction in the antioxidants and increase oxidative damage to the cornea, another theory that has been proposed. Matrix metalloproteinase-2 is also activated and changes the extra cellular matrix surrounding the corneal cells. Keratocytes are numerous cells in the cornea that produce the collagen for the fibers and the extracllular matrix components, turning mostly dormant by birth. In Keratoconus they have been observed to have increased apoptosis (increased programmed cellular death). There us a reduction in the number of collagen fiber and they also reduce in diameter. Most likely, keratoconus will be found to be several different disease processes and also multifactoral. Multifactoral eye diseases have multiple factors that combine to create the eye condition. For instance, the different collagen structure in the central cornea makes the eye susceptible, changes in enzymes may alter the tissues and start causing minor breakdowns in the epithelial surface cells, enzyme changes may lead to increased oxidative stress further weakening the eye tissue, and constant rubbing of the eyes may push the eyes over the edge by inducing mechanical damage to the eye tissues that could only occur with a compromised cornea. A genetic alteration of the cornea could make the cornea of the eye more susceptible to the entire chain of events.

Your eye doctor will initially treat Keratoconus with contact lenses

Treatment of Keratoconus usually begins with a rigid gas permeable contact lens when vision can no longer be maintained clearly with spectacle lenses. Sometimes, a gas permeable lens will be fit over the top of a soft contact lens in a piggyback contact lens fitting, with a soft contact lens and a rigid gas permeable contact lens on top of it. While used years ago, piggyback contact lens fittings fell out of favor due to the complications from reduced oxygen flow with older soft contact lenses. With the new super oxygen permeable silicone hydrogel soft contact lenses, it is enjoying a small resurgence. It is primarily used to increase eye comfort for the keratoconic eye patient. There are also combination contact lenses available today, such as the SynergEyes contact lens that is a rigid contact lens with a soft skirt attached surrounding the lens. The primary issue with Keratoconic contact lens fittings is matching the steeply curved cone with the surrounding flatter eye tissue, while dealing with the irregularities of curvature that are present. While custom mapping technology is highly touted as the way to achieve the required fit, the truth is observation of contact lenses on a keratoconic eye by an optometrist and adjustments based on how dyes accumulate under the contact lenses is still the most accurate method to achieve an excellent final fit. Due to the drastic changes in curvature the contact lenses require multiple different curves as you move toward the edge of the lens. While many different lenses have been developed with special names as the ultimate Keratoconus contact lens, they are all variations on the basic concept of a steep contact lens center and a gradient of changing curvatures to the edge. Rigid contact lenses work because the light bending capacity of the tears is very close to the light bending capacity of the cornea. The tears fill in between the irregular eye surface and the smooth surface on the back of the lens. This essentially removes the irregular astigmatism and nearsightedness by utilizing the back contact lens surface as a new regular surface where light is altered, and often restores the corrected eyesight close to 20/20. Eye glasses may only achieve 20/40 vision or much worse because the irregular surface remains. Occasionally Scleral rigid gas permeable lenses are used. These are gas permeable lenses larger than normal that extend out onto the white part of the eye. All contact lenses today are gas permeable, or designed to let air pass through to keep the cornea healthy. Soft contact lenses are usually not referred to as gas permeable because of historical changes. Hard lenses were the first contact lenses and they were made of a material that passed no oxygen through the lens. When changes were made to the polymers used to make hard contact lenses that allowed them to breathe or pass needed air to the underlying cornea, they were renamed rigid gas permeable contact lenses. Rigid because they are still a hard material with only 1-2% water, and gas permeable because unlike the older hard contact lenses they now transmitted air to the eyes. Soon they became called by the acronym of RGP’s to save a few words (even prior to the texting era). With time they also came to be referred to as gas perms, in spite of the fact that all soft contact lenses are also gas permeable. Soft contact lenses are never rigid however, as they normally are composed of about 50% water. This softness comes at the price of increased flexibility and they drape across the eye, imitating the irregularities of a Keratoconic cornea and do not correct the vision back to optimum levels. Once your eye doctor has achieved an excellent fit and optimized your contact lens prescription, there may be frequent changes in your contact lens prescription as the Keratoconus goes through progressive changes.

Your Eye Doctor May Be Able to Avoid Corneal Transplants

While only 10-20% of eyes will undergo ongoing serious changes, they do present challenges to fitting contact lenses on eyes with Keratoconus. At some point, scarring of the cornea can start to occur and patients become intolerant to contact lenses. In years past, the only remaining option was a corneal transplant. While corneal transplants enjoy a relatively high success rate, there are still risks and problems. Recently there have been some new exciting options starting to evolve.

Permanent Contact Lenses-Intacs

Intacs are small rigid half rings similar to portions of a gas permeable contact lens that are implanted in the cornea. They were originally developed to reverse nearsightedness, but did not prove as effective as originally thought and were replaced by LASIK eye correction procedures. A few years ago they found a new use in stabilizing Kerataconus. They are not a cure for Keratoconus, but can restore some more regularity and allow some patients to continue contact lens wear while avoiding a corneal transplant. They also appear to have some effect in decreasing the rate of change in Keratoconus. While they are promoted as being completely removable and reversible if patients have problems, this is not entirely true. About 10-15% of Intacs cause some complications and issues that cannot be resolved if they are removed. Still, it is a better option than jumping straight to a corneal transplant.

Keratoconus Corneal collagen cross-linking therapy

Corneal collagen cross-linking therapy (CXL) is intended to stabilize the tissue by forming more bonds between the existing collagen fibers and also increasing the size of the fibers, making the cornea much firmer and less likely to continue deforming. It involves pretreatment the cornea with riboflavin (Vitamin B2) for 30 minutes then using radiation from the ultraviolet A band light spectrum (normally around 370 nanometers) to increase the cross links over about a 30 minute period. While it has been more extensively in Europe, it is starting to enter the U.S. market. The riboflavin acts to keep the UVA from completely passing through the cornea so the UV can act to create more cross links. Riboflavin also may have a photo reactive effect that further increases cross linking of the collagen bands. Questions still surround this treatment. It is not an FDA approved treatment in the United States but is undergoing clinical trials, and currently is used off label as a treatment for Keratoconus. The FDA (Food and Drug Administration) regulates drugs and medical devices but not doctors. Any procedure that uses drugs or medical devices can be performed by a doctor if you are properly informed, share in the decision, and it has an acceptable possibility of helping. The riboflavin still allows a significant amount of UVA to pass through the cornea. This could potentially increase future risks for cataract development. UVA with riboflavin is cytotoxic (damaging to cells) and can damage the endothelial cells that line the back of the cornea and are vital for its long term health. Corneal thickness needs to be factored to keep this type of damage far enough away from the endothelium cells of the cornea. A minimum corneal thickness of 400 microns has been suggested but a better choice would be 450 to 500 microns. Cellular damage to the keratocytes, changes to the matrix of the cornea, and changes to the epithelium do occur in the cornea after the procedure. Normally they regenerate over the next 6 months. Riboflavin has poor penetration into the cornea so the surface layers of epithelium cells need to be removed. It is unknown if the effect of increased rigidity created by this treatment will last indefinitely, or if there are any other long term problems from increasing the cross linking and rigidity of the cornea. Some cases of persistent haze, infections, and increased eye pressure reading have been noted. The increased eye pressures are presumably an artifact since we know thicker (more firm) corneas read artificially high with most current glaucoma instruments. With careful consideration about the stage of Keratoconus and treatment of the eye at the appropriate stage, cross linking of collagen fibers in the cornea appears to be a great addition to eye doctors armetarium in treating keratoconus. While it may improve the condition mildly in many patients, it should always be considered as a stabilizing treatment and not a curative treatment.

Future therapies will evolve. Cross linking collagen therapy is still in its infancy. Stem cell and genetic treatments may be seen at some time. Someday we will no longer be treating Keratoconus but acting to prevent it from ever distorting peoples vision and lives.

Eye Doctors Dry Eye Secret Treatment

Dry eyes can be a very debilitating condition. It is very common in low humidity climates like the Fort Collins area, and it can interfere with contact lens wear and comfort. It can also be a severe problem after LASIK corrective eye surgery. Optometrists have a number of different options to treat dry eye syndrome  and contact lens intolerance today, and TheraTears non preserved artificial tears have proven very useful to eye doctors. TheraTears has some unique properties that can actually help restore the eye tissues instead of just treating the symptoms of burning eyes, gritty eyes, and general discomfort.

The tear film covering the front of the eye has been the subject of extensive study by eye doctors over the last decade. It is composed of a water component, a mucous component, and a lipid component. Every time you blink, your eyes experience a resurfacing of the tear film. When things go right, the new film has adequate water and retains its integrity until your normal blink reflex recurs. When things go wrong comfort and cells that produce the tear components are compromised.

The water component of tears has a normal value for osmolarity which is related to how much the salt concentration is in your tears. When the water levels decrease, the same amount of salt is present so the relative percentage of salt in the tears increases. This draws more water out of the corneal tissue on the front of the eye and can damage the surface cells known as the epithelium layer. The high osmolarity levels also decrease the amount of goblet cells. These are the cells that produce the mucous component of the tear film that makes the tear layer slide out across the eye surface. There are electrolytes like sodium and chloride in the tear film that are essential to keep the osmolarity in a normal range and also help the proteins like lactoferrin dissolve in the tears. Lactoferrin is a protein that fights against bacterial and fungal eye infections. It also serves to reduce eye inflammation. Because the cornea tissue on the front of the eye has no direct blood supply, a healthy tear function is vital to maintain good eye health and vision. Even from this brief view of the tear film, you can see how important it is to your optometrist that this complex system is functioning normally.

So now one of the best kept secrets of eye doctors in treating dry eye disorders and contact lens discomfort-TheraTears

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And there is a little known way of using TheraTears to achieve the correct effects called saturation dosing. Saturation dosing involves taking one vial of TheraTears and emptying it into the eyes over a five minute period for times a day for at least a few weeks. It helps restore the salt content levels back to normal and allows goblet cells to regenerate. It is specially formulated to stay on the eye for about 30 minutes. The electrolyte content is similar to what a normal eye would be so it helps readjust this also. After a few weeks your optometrist can decide when you can discontinue the saturation dosing and start a single drop several times per day. Often the tear film regains a significant amount of its integrity and the burning, dry eye discomfort stops. Sometimes the simple things work best.

When You Optometrist Says You

Have Astigmatism Don’t Start

Planning an Eye Funeral

Often patients who have changed to a new optometrist find themselves being alarmed when told they have astigmatism. Frequently it is the first time they are aware of a new eye condition and it is cause for concern. In most cases, their eye doctor did not mention they had astigmatism in years past, probably because it was a low amount. On occasion, the patient believes they are being told they have a stigmata and are even more upset.

Astigmatism can be caused by curvature on the corneal tissue on the front of the eye, or by the curvature and light bending power of the lens inside the eye. About 2/3 of astigmatism is caused by unequal curves on the corneal tissue on the front of the eye. Normally, this is regular astigmatism meaning there are two different curvatures that follow a smooth pattern. It can best be visualized as an eye that is shaped like a tennis ball being squeezed on top and bottom to produce two different curvatures. Irregular astigmatism does occur in some eye diseases like kerataconus and occasionally after corrective eye LASIK surgery and corneal transplants. This is a form of astigmatism you should be concerned about. It is more like the shape of a potato with dips, valleys, and hills representing the curvature. Obviously it is hard to grind a corrective lens to this shape and often gas permeable rigid contact lenses are required to achieve crisp vision. New alternatives today include the SynergEyes contact lenses that have a soft contact lens skirt surrounding a rigid gas permeable center. Since the human tears have the same light bending capacity (index of refraction) as the cornea, when the tears fill in between the contact lens and the eye a new smooth surface is produced. If you have irregular astigmatism ask your optometrist about the new options available to see clearly.

Astigmatism is common in moderately high amounts in infants and toddlers. It often self corrects. Your optometrist may want to closely follow your child’s vision and delay eyeglasses for a few years. If the astigmatism is judged to be too high by your eye doctor or persists past the first few years of childhood, it needs to be corrected with prescription eyeglasses.

In some cases when a very young child is incapable of wearing glasses contact lenses may be used

Children may be fit with contact lenses for astigmatism that can be worn for 30 days without removing, or with daily disposable contact lenses that are removed every day by the parent. Large amounts of uncorrected astigmatism can result in a lazy eye. This can result in permanent vision loss, and with high astigmatism in both eyes it could result in bilateral loss of acuity. With proper treatment by your optometrist this is a completely preventable type of partial blindness.

Once you aware you have astigmatism there is no need for panic. You probably have had it for a number of years. Most of the population has at least some small amount of astigmatism. In most cases it changes very slowly over time. Over the course of a lifetime you will blink your eyes millions of cycles. The pressure exerted by the eyelid as it rubs across the cornea over years of blinking probably contributes to very slow changes in astigmatism. While there is no evidence supporting my theory, I do believe that tilting your head and paper along with other postural and ergonomic factors cause a slight blurring of your vision at an angle that can cause astigmatism to develop or change. Blurred images to the retina tissue inside the eye are known to cause near sightedness. Large degrees of astigmatism are found in several Native American populations, especially in the four corners area bordering Colorado. These are genetic passed on through the generations.

In most cases there is no alarm needed if you find out you have astigmatism. It will probably show only small changes over long periods of time, and in many cases stabilizes for years. When in doubt call your optometrist back and explain your concerns.

Many eye doctors office claim they provide specialty contact lenses or are contact lens experts. We know the frustration you feel when it turns out they are really only interested in simple cases they can shuffle in and out the door in a hurry.

Don’t call us if you have special contact lens challenges that you want solved in an hour.  We don’t want to waste your time.

Please do call us if you want your contact lens problems solved and are willing to dedicate the time needed.

Specialty Contact Lenses We Provide Include:

• Kerataconus-This is an eye disease where the clear corneal tissue on the front of the eye thins develops a very steep curvature with an irregular curvature. A cone shaped protrusion forms on the cornea. Many different special contact lens designs are used to compensate for this shape including soft contact lenses, gas permeable lenses such as the Rose-K designs, hybrid lenses with soft lens material on the outer edges and RGP rigid gas permeable materials on the inside, piggyback lenses that combine a gas permeable lens on top of a soft lens, and scleral lenses that extend over the white tissues on the eye. Kerataconus contact lens fitting is still very much an art form with no exact science.
• Cosmetic Lenses For Eye Damaged by Trauma: The colored part of the eye, the iris may be mishaped from birth or by trauma leaving an oddly shaped pupil. Specialty Colored Contact Lenses can be used to restore a normal pupil appearance and cut down on glare and discomfort from a malformed pupil.
• CRT or Orthokeratology Contact Lenses: Gas permeable lenses can be used in some cases to reshape the corneal tissue on the front of the eye and reduce nearsightedness (myopia). This is often done by wearing a lens overnight so the eye is prescription free during the day.
• Large Amounts of Astigmatism: New advances in contact lens technology allow for large degrees of astigmatism to be corrected by contact lenses. Usually the comfort of soft contact lenses can be  used in a disposable contact lens for health and comfort.
• Contact Lenses After LASIK Laser Eye Surgery: LASIK doesn’t always work and the eyes may be left with a very irregular surface. They may also be left with residual corrections and change with time. These issues can be solved with specialty contact lenses, when glasses may not provide a good correction due to irregularities in the astigmatism.
• Color Vision Defects: While contact lenses cannot restore normal color vision they can make it easier for some patients to discern differences.
• Nystagmus or Eye Tremors: In some cases, rigid contact lenses can supply feedback to the brain about these uncontrolled eye movements and help dampen the eye movements to some degree.
• Contact Lenses For 40+ Year Old Eyes Needing Bifocals: If your arms are getting too short too read, don’t despair-bifocal and mutlifocal lenses are available in many different designs in soft and gas permeable contact lenses. Expect to spend some time being fit.

Most children by the age of 12 become concerned with their looks. Most parents breathe a little sigh of relief that they do. As we all know, this relief may also soon be followed with the horror of what teenagers equate with good appearance. The story is ancient and never changes but somehow the image they aspire to always manages to shock the previous generation. Who would have thought vampires?  Once they become teens this concern is in full effect.  Everything from their clothes, their hair, their shoes and their skin is of the ultimate concern.  Eyeglasses that once were OK to wear, may now make your teen unhappy and self conscious. They may now be interested in a new look  that wearing contact lenses may provide, while also boosting the oh so fragile self esteem of the typical middle school teenager.

With teens, contact lenses must be considered carefully.  If your teen only needs glasses for reading, contact lenses may not be a great option.  Even though they feel like they are wearing their glasses a lot at school, if their contact lens prescription is low they might be unwilling to adequately care for the lenses and discontinue wearing them within a few months. If they are determined to try contact lenses for a low eye correction and you are OK with this possibility, you and your teen then make an appointment with an optometrist for an eye exam.

Your eye doctor will be able to best advise on your teen’s vision.  If astigmatism is present, toric contact lenses may need to be prescribed for clear vision. There are new advances in contact lenses that correct astigmatism, but each case is different. Eyeglasses may offer the clearest vision on the eye chart, but the difference gained in peripheral vision may be so significant that the teen feels their vision with contact lenses is far superior to eyeglasses.

Once contacts are prescribed there will be an adjustment period.  First the teen must learn how to properly insert and remove lenses on the eye. This is a prerequisite for leaving the office with contact lenses. Sometimes it may take several office visits to reach this skill level, but most teens are so highly motivated they learn extraordinarily fast. They must also learn how to properly clean them.  This is essential to good eye health.  Hands must be washed before touching the lenses to reduce the chance of eye infections such as pink eye. The lenses should be removed each and every night and washed, then put into a contact lens case filled with disinfecting solution overnight. The contact lens case should be replaced every one to two months and not look like a teen microbiology experiment.  Even if the lenses dictate that they can be worn overnight, this is not a good idea for a teen. It is an excellent idea to use one of the new generation 30 day wear lenses for teens on a daily wear basis. I have yet to met a teenager who doesn’t fall asleep during the day at times.Unbelievably , they are often seen sleeping in class! These silicone enhanced contact lenses are super permeable to oxygen and provided an added margin of safety for that occasional nap. Extended continuous wear over night and on consecutive days can damage the cornea as well as cause painful eye infections and loss of sight when teenagers make mistakes in care and handling. As a parent, you should always be present for contact lens care instructions for first time lens wearers

Remember that teen’s eyes are still changing as their body is and eye care should be followed with regular visits to the eye doctor. Never allow a teen to have contact lenses without a pair of glasses. While they may rarely the eyeglasses, the first time they continue wearing contact lenses on an eye that is irritated may be the last time they see clear out of that eye for the rest of their life. They need the option to remove a contact lens from a possible eye infection and wear glasses until they visit the eye doctor. And yes, if you really areok with it there are vampire contact lenses.

There is a difference between eye exams for contact lenses versus eye exams for eyeglass wearers. When making an appointment for an eye exam, express your desires for either eyeglasses or contact lenses.  Typically, people already wearing eyeglasses schedule appointments to switch over to contact lenses. The motivation may be cosmetic, better peripheral vision, or for athletics. Those who have never worn glasses and find out during a routine eye exam that they need corrective lenses can discuss their options with the eye doctor. Then they can choose to either proceed with a contact lens exam and fitting or come back at a later date after careful consideration of the options that will best fit their lifestyle.

An exam for eyeglasses consists of a series of tests performed by the eye doctor and their technician. A computer aided analysis is performed by the optometrist by asking you to stare at a certain point in an instrument. By doing this, the doctor is determining how the light wave is altered as it bounces off the inside of your eye. This gives the doctor a good starting point for the strength of prescription you need. A Refraction test is also performed with a Phoropter where you will look through a mask like device at a series of letters.The doctor flips lenses in the mask and asks when it looks the most clear. This is the dreaded point of commitment to one or two. Since it is a forced choice test (that is a psychological term for being restrained in the exam chair until you decide on two horrible, blurry options) many patients feel uncomfortable with deciding on an answer. While this may feel like a day in the voting booth, you need not worry. A vision exam never relies on a single answer. Also, the lenses may change even though the number stays the same. Occasionally patients worry that it was clearer in a previous view, or even in between changing views. Since you can’t see the exam from the eye doctors point of view, you can’t see the logic in what may appear to be faulty testing. Don’t be concerned, repeated testing sequences assure that your answers are reliable before a prescriptions is finalized. The result is a clear determination of whether you are nearsighted or farsighted, whether you have astigmatism and whether presbyopia is present.  Last, the doctor will perform a slit lamp exam and examine the inside of your eye to look for eye diseases such as glaucoma, cataracts and macular degeneration.

During a contact lens exam, the cornea surface is the center of the exam.  The doctor runs tests to assess the cornea to get the right fit for the contact lenses.  An instrument measures surface and curvature of the eye. It works like a digital camera that takes pictures of the eye and creates mathematical depictions of the curvature of the cornea surface.  This gives the doctor the sizing for the contact lens.  A microscope is used to determine the health of your cornea and your  pupils may need to be measured if you are being fit for bifocal contact lenses.Your tears may be measured with a tear film evaluation to determine the amount of eye moisture in the eye as well as a fluorescent dye that is placed in the eye to see the quantity of tears present and any cellular compromise to the cornea. Careful attention is paid toward analyzing the eyelid margins and the clear tissue covering the white part of the eyes and under the eyelids for any signs of eye disease or problems that may interfere with successful contact lens wear. After testing, the doctor will select a contact lens that best matches your eye. This lens is usually fit for a trial period to make sure your eyes are adapting in a healthy manner. More complicated contact lens fittings may require several visits to find the optimum lens for your eyes. In cases where bifocal contact lenses or contact lenses for eye conditions causing  irregular astigmatism this may take several months to reach a finalized prescription.

In its important to remember that contact lenses are never a replacement for eyeglasses. I have seen numerous cases where patients wearing contact lenses did not have a pair of prescription eyeglasses and acquired an infection, a scratched eye, or a particle of metal lodge in the cornea tissue on the front of the eye. Having no backup option when away on a trip they continue to wear thier lenses and the end result can be scarring and eye damage. Always having a backup pair of spectacles is priceless in preserving your eye health.. This is even more important with teens and children who tend to not complain until their eyes are already in an advanced state of compromise. Because they are more concerned with appearance at certain ages, they are much more reluctant to understand the necessity of eyeglasses as an emergency preventative health device.

Contact lenses are a medical device controlled by the Food and Drug Administration and should be given the care an respect as any other medical device. Part of this care is an annual eye exam that assures your eyes are continuing to have a healthy adaption to this marvel of technology, first envisioned by Leonardo da Vinci in the 16th century.

We still see allergies to the preservatives in contact lens solutions in our Fort Collins Contact Lens Clinic but at a much lower frequency than in the past.

Thimerosal, (sodium ethylmercurithiosalicylate)  is an older contact lens solution preservative whose composition is about half mercury. It as commonly used in very low doses in contact lens disinfecting solutions is an excellent preservative but causes a reasonably high number of allergic reactions. It has been used in childhood vaccines and a subject of controversy over the years as a possible cause of autism. There are no significant studies to confirm a relationship,  but similar to contact lens solutions, it is being phased out. You will often see vaccines that are touted as mercury free.

Chlorhexidine is a chemical antiseptic that is very effective at killing bacteria. It was also widely used in the past in contact lens solutions prescribed by eye doctors but frequently caused red eyes, vague forms of  eye irritation, and sometimes significant conjunctivitis and  discomfort. Like Thimerosal, it has largely been phased out of contact lens care and we never reccomend it in our Ft Collins Eye Practice. It is still widely used in the dental field to treat gum disease and as a disinfectant.

Benzalkonium chloride was used in the past and is still used today is some nasal sprays, cleaning solutions, and various other hygienic products. It is a good disinfectant but at high enough levels may not only serve as an allergen but cause serious damage to the corneal tissue the contact lens rests on.

The next generation of sensitive eyes contact lens solutions proved to have about the same rate of allergic reactions, just for different people. Switching often cured the problem for those allergic to former solutions but created problems for new users.

Many generations of solutions have since come to pass. Today the large molecule preservatives are favored by optometrists since they fail to build up in the contact lens matrix, exceeding the pore size of the lenses.

The problem today rests in generic contact lens solutions, often colored and labeled to look like the brand solutions. Sometimes they are OK, at other times they are using these older toxic preservatives that should have been off the market a long time ago. To compound the confusion, the formulations may change in the middle of the shelf for the same generic brand, even though the box appears identical.

The best bet today is to stick with a brand name solution your eye doctor reccomends or use one of the hydrogen peroxide based systems. The drawback to hydrogen peroxide has always been it is too easy to make a mistake, and hydrogen peroxide is very uncomfortable when placed in your eye without neutralization!

Spend a few extra minutes during your next visit to the optometrist and ask their advice on what is the best contact lens care regimin avaialbe to keep your eyes healthy and seeing well.

Babak A. Parviz of the University of Washington is working on futuristic contact lens technology. His research includes work on contact lenses incorporating sensors for glucose monitoring for diabetics and potentially contact leness as display monitors out of the science fiction realm. If you are interested in where contact lens technology may lead to in the future his work and publications are a fun read.

In terms of futuristic contact lens technology the question remains where the corneal molding technology disappeared to. Several years back a California company had developed a permanent technique for reshaping the cornea to adjust the prescription. It involved a prescription medication to soften the collagen bonds of the cornea temporarily, and several days of rigid contact lens wear to reshape the tissue while in this malleable state. Oddly, it seems to have vanished after having some very positive reports.

Current technology not being used clinically allows determing blood glucose levels by utilizing laser or infared light directed into the fluid inside the anterior chamber, the front part of the eye. This fluid is referred to as the aqueous humor and the glucose levels allow an estimation of the blood levels.

A new type of contact lens should be on the market within a year. Developed at Harvard University it will allow constant steady release of eye medications instead of the variation in dosing levels that ocurrs with prescription eye drops. Other competitors are in the market. I have seen the effectiveness of this using todays contact lenses saturated with eye medications in off label applications. It should be a great option for certain eye diseases. I suspect glaucoma will be one of the first contact lens applications where it will deliver results like an insulin pump can for a diabetic who has wide swings in blood sugar levels when control was tried with injections.

Patents exist for photochromatic contact lenses that darken with sunlight and act as a sunlens. When this will see the “light of day” is unknown. Patents also exsist for liquid contact lenses. Researchers have looked for eyedrops to act as temporary corrective liquid lenses for years-maybe someday an eyedrop a day will keep the eye doctor at bay.

Contact lenses with added components to prevent infections are under study and probably will reach the market place in the next few years.

Custom eye specific shaped contact lenses are certainly going to be a part of the future. Wether you know it or not, you suffer from more vision problems than nearsightedness and astigmtism. You also have trefoil, quadrafoil, spherical abberation and other optical misfortunes degrading your vision. The future will only look better!