Cataract surgery has become commonplace, and the recovery time is now a fraction of what it was. But if you could avoid cataracts, wouldn’t you? Here are some things you should know about cataracts.
6/9/15
Courtesy of the National Eye Health Education Program (NEHEP)
a program of the National Eye Institute (NEI), a part of NIH.
Corneal dystrophies are a debilitating group of progressive diseases that can ultimately deprive a person of sight. The cornea, which forms the front of the eye, is a window for vision, and dystrophies due to intrinsic defects in the corneal tissue cause this window to become opaque and hazy. Fuchs’ dystrophy, also known as Fuchs’ corneal endothelial dystrophy (FCED), is amongst the most commonly diagnosed corneal dystrophies requiring corneal transplantation. The ophthalmologist Ernest Fuchs first described the disease in 1910.
The disease is rare, and it is difficult to predict who will get it. We know that it affects women more than men (3:1 ratio), older adults (older than 50 years of age), and those with a family history. There are forms in which there could be up to a 50% chance of transmission to children of parents with Fuchs’ dystrophy. Most cases, however, occur sporadically.
Although the cause of Fuchs’ dystrophy is still being studied, there are characteristic findings associated with it: small outgrowths on Descemet’s membrane called “guttae” or “guttata”, thickening of Descemet’s membrane, and defects in the endothelial cells (Figure 1).
Descemet’s membrane is a thin corneal layer between the endothelial cell and the stromal layers of the cornea. Endothelial cells make up the backside of the cornea and function as a barrier and pump for keeping fluid out of the cornea and maintaining corneal clarity. As guttae accumulate on Descemet’s membrane, patients experience progressive loss and change in endothelial cells. Dysfunction of endothelial cells causes corneal swelling, which distorts vision. First, the back of the cornea swells, and eventually, swelling can reach the epithelial cells at the front of the cornea. Swelling can range from mild moisture accumulation, to painful “bullae”, or blisters. In very late-stage disease, significant corneal scar tissue can form and dramatically reduce vision. The progression to late stage Fuchs’ varies from person to person, but usually takes a couple of decades.
A patient may be asymptomatic for years despite having guttae. Initial symptoms, including blurry, hazy, or cloudy vision, are typically due to corneal swelling from dysfunction of the endothelial cell layer. Patients may also experience glare or halos around light in the early stages just from the density of guttae. New studies suggest that patients can get glare and higher order aberrations from guttae without any corneal swelling. Symptoms tend to be worse on awakening, but usually improve throughout the day. This is because the closure of eyelids during sleep results in the accumulation of fluid in the cornea. For the same reason, humid weather can also worsen symptoms. As the disease progresses, poor vision may last longer into the day. There may be associated pain if blisters develop.
The presence of any of the above signs and symptoms, especially with a family history of Fuchs’, should prompt a consult with an ophthalmologist who will diagnose the disorder and follow its progression with regular checkups. An ophthalmologist will conduct a microscopic slit-lamp examination of the eyes, looking for guttae and Descemet’s membrane thickening (Figure 2).
Special tests may be done to measure corneal thickness, a marker of swelling, or count endothelial cells to track disease progression (Figure 3 and 4).
Management can be medical or surgical depending on symptoms. Patients may have mild or slow progression of disease that can be managed medically including over the counter salt solution drops (5% NaCl) to reduce corneal edema.
When there is late-stage disease, a corneal transplant may be necessary to improve vision. A corneal transplant replaces the patient’s corneal tissue with human donor corneal tissue. Donor corneas are readily available via excellent eye banks throughout the United States. The surgery is outpatient surgery with regular follow-up appointments and suture removal during the subsequent months. The postoperative healing of the cornea and vision stabilization can take up to a year.
Great strides have been made in the last decade in corneal transplantation surgery, giving patients better treatment options. Patients used to be limited to penetrating keratoplasty (PK), a full-thickness replacement of the cornea. We now have newer surgeries known as endothelial keratoplasty (EK), which is a partial-thickness transplant that replaces only the damaged part of the cornea (the endothelial layer). The different types of EK are DSEK (Descemet’s-Stripping Endothelial Keratoplasty) and DMEK (Descemet’s Membrane Endothelial Keratoplasty). The techniques vary by thickness of the transplanted tissue. The type of EK most appropriate is determined by the corneal surgeon and is variable on a case to case basis. Both types of EK surgeries provide comparable long-term visual results. In both surgeries, the patient’s diseased Descemet’s membrane and endothelial cells are stripped from the inner layer of their cornea. The thin lamellar donor graft is then inserted into the eye and positioned onto the back of the patient’s cornea via a gas or air bubble. The patient is then instructed to lie in a face up position for several hours post surgery during which time the bubble supports the graft until the new endothelial cell pumps begin to wake up and naturally adhere to the back side of the recipient cornea. Occasionally, the doctor may replace another air bubble into the eye the next day to allow more time for the graft to adhere. Visual recovery is on the order of 1-2 weeks in DMEK and 2-3 months in DSEK surgery. Rejection risk is still a possibility in EK surgery but has a much lower rate than traditional full thickness PK surgery.
Other surgical considerations depend on the presence of cataracts. Cataract surgery can worsen Fuchs’ dystrophy because of damage to the endothelial cell layer. For this reason, patients with cataracts and Fuchs’ requiring surgical intervention are often recommended to undergo cataract surgery before or at the same time as corneal transplantation to ensure the best outcome for the transplant.
Patients should work with an ophthalmologist to determine the best management plan. Ultimately, vast improvements in treatment options have given many Fuchs’ dystrophy patients the exciting opportunity to regain vision with improved healing times and reduced infection and rejection of the graft.
Citations: Figure 2 and 4 are from Zhang J, Patel DV. The pathophysiology of Fuchs’ endothelial dystrophy—a review of molecular and cellular insights. Exp Eye Res. 2015 Jan
6/4/15
Priscilla Q. Vu, MS
Medical Student
University of California, Irvine School of Medicine
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Marjan Farid, MD
Director of Cornea, Cataract, and Refractive Surgery
Vice-Chair of Ophthalmic Faculty
Director of the Cornea Fellowship Program
Associate Professor of Ophthalmology
Gavin Herbert Eye Institute, University of California, Irvine
It’s an extremely rare person who would not feel nervous before surgery of any kind, even if it’s an outpatient procedure that will only take a few minutes. In the case of cataract surgery, the fear can be even worse than the procedure itself.
People who are under intense stress can suffer a range of symptoms, including irregular or racing heartbeat, nausea, upset stomach, difficulty breathing, and an inability to sleep. It can even affect your mind, causing you to forget important details about the operation, like advice on how to get ready or what to do after you come home from surgery.
1. Just Think About It – Let’s start with the first, and most difficult, suggestion—change your own mind about how you feel. Admittedly, it takes a great deal of discipline that’s hard to muster in the face of great anxiety, but try to remind yourself how your sight will be saved after a relatively short, quick, and easy procedure. What you are about to go through will prevent you from going blind.
2. Learn Everything You Can – For many, it helps to learn as much as possible about the surgery before it happens. Knowing exactly what’s going to happen and how others have dealt with what you’re going through can be a great relief. Knowledge may be all you need to relieve your anxiety.
3. Talk to Your Surgeon – It almost always helps to just talk to someone, and who better than your surgeon? Who else knows every detail of the procedure you’re about to undergo? It’s fairly likely that your surgeon has performed many successful surgeries of this kind before, and he or she may have some stories of encouragement for you, as well as important and comforting knowledge of his or her own personal experiences.
4. Imagine the End Result – It may help if you keep focused on what happens after, as if it’s already done and you can go home, the procedure over. This takes a great deal of imagination, rather than the discipline of thinking rationally about it, but if you have that level of imagination, it’s certainly worth trying.
5. Alternate Methods – This encompasses a whole range of stress-reducing tactics that are not usually under the medical umbrella. Nevertheless, they have done a great many people a lot of good. Yoga, hypnosis, massage, acupuncture, acupressure, and other treatments have allowed those suffering preoperative stress to sleep better at the least.
6. Herbal Supplements – A form of alternative treatment involving traditional ingredients to produce a more restful state. The herbs are often just infused into tea and drunk. While these supplements are generally called “all natural,” you should always consult your doctor before taking them, since they can have an effect on other medications you may be taking, including the anesthetic you are given before surgery.
7. Have Some Fun – Do something fun to take your mind off of what’s about to happen. Whatever that specific thing may be is up to you, since an individual’s idea of fun differs from person to person. Whatever you generally do to take your mind off of things and unwind after a hard day may be just the thing to help you out before undergoing cataract surgery.
8. Treat Yourself – In the same vein has doing something fun, do something that usually relaxes you. If you like going for long walks, do that the day before the surgery. Or listen to music that fills you with peace (or joy). Take a long bath. If it makes you feel relaxed or calm, it will help you deal with your anxiety.
9. Distract Yourself – Once you get to the hospital, you’ll probably be waiting around, even if you get there right on time, giving plenty of time for stress to ramp up. You’ll do better if you keep yourself entertained, but the hospital waiting room is probably one of the more boring places on earth. Fix that by bringing something along to entertain yourself, like a book or some magazines, or even stream your favorite movie or podcast. You’ll probably want to bring more than one thing to do, in case the wait is long.
Stress adds complication to the body’s systems, and can therefore cause some complication in the upcoming surgery. Do what you can, whether you kick back with friends or take some herbal supplements, to help yourself get into the best mind space possible. Think about the positive outcomes, and you’ll do well.
In the beginning…of contact lenses…there were scleral lenses…only.
In the year 1887 a great gift was given to the world of sufferers of distorted vision resulting from corneal tissue that was irregular in shape from disease or trauma.
The contact lens was invented nearly simultaneously by physicians working separately in Germany and in France. Working from drawings of Leonardo da Vinci (1508) and ideas of the British astronomer Sir John Herschel (1828), August Müller and separately Adolph Fick and Eugene Kalt blew glass shells to fit the outer eye and to some extent remedy their visual difficulties. These lenses rested on the conjunctiva of the eye above the sclera or white of the eye and were thus the first scleral contact lenses — the first contact lenses of any sort.
The design and manufacture of scleral lenses has been a story of technological development significant for improvement in comfort, material, and affinity for the ocular surface.
For many years the lenses were partially molded and partially ground from the material of which hard contact lenses are made: PMMA (poly-methyl methacrylate) known as Plexiglas or Perspex. To form these lenses, like tooth implants, a plaster cast is made from a negative mold prepared from dental impression putty. The plastic would be heated and given the shape of the fitting surface of the lens from the plaster cast and then the power and edge curves would be ground onto the outside surface of the lens. Later came preformed trial sets not unfamiliar to those which we use today.
The current generation of scleral lens fitting began sometime in the last fifteen years with the mating of advanced corneal topography measurements, computer driven lathes and the observations of some very clever contact lens scientists. Proprietary designs of scleral lenses offering a variety of diameters, fitting philosophies, and multiple parameters are filling the gaps contact lens specialists have been wrestling with using smaller corneal contact lens designs for decades with less than optimal results. Most recently a firm has begun manufacturing lenses with a 3-D printer from an image generated from the eye. One eye…one lens, the lens is meant to fit like a fingerprint.
When discussing contact lens treatment, experts are experts because they agree that, any sort, size, or design of lens will have both positive and negative effects on the eyes and the tissues surrounding them. While it is true that many of the fitting and comfort issues confronted with corneal lenses of any size and design can be managed well with scleral designs, the scleral lens can also be difficult for some patients; for some eyes; for some conditions.
From the outset the larger size of the today’s scleral lens provides comfort on par with soft contact lenses for exactly the same reason: their size. Also, like soft contact lenses the scleral will not move around on the surface of the eye allowing the wearer a much more relaxed contact lens experience — there is no necessity to balance small corneal lenses between tense eyelids – vision can be enjoyed in any direction of gaze. The lenses will not fall off the eye and the increased size is a clear plus in finding a dropped contact lens.
On the other hand the quality of vision gained with scleral lenses specifically in cases of distorted corneae is far more comparable to that achievable with corneal GP lenses than with soft contact lenses in most cases.
Over the years my keratoconus patients have benefited from a series of contact lens breakthroughs that have variously improved the quality of their vision, their comfort with contact lenses, or in some other way the health of their eyes. Some years ago I “re-invented” the piggy-back system of contact lens wear which I summarized in 2008 in an article published in the Contact Lens Spectrum. Piggy-backers would place their vision restoring firm contact lens on top of a disposable daily wear lens of minimal focusing power. The soft lens would reduce the sensation of the firm lens while in many cases preventing the contact lens from abrading the cornea. More recently I have been successfully moving patients to scleral lenses because there is certainly less bother (only one lens per eye) and far less worry over corneal abrasions as the lens rests on the conjunctiva over the sclera and maintains a fluid cushion over the cornea itself.
Scleral lenses are finding their place in the world of contact lens fitting primarily to remedy vision problems from very irregular or otherwise damaged corneae both those caused by developing disease and trauma through injury or surgery. More and more, these lenses are requested by patients with normal eyes who want to enjoy the benefits provided by these lenses while participating in sports or other activities.
Scleral lenses are renowned for their greater comfort. In many cases a correctly fitted lens can be worn for many waking hours. Many patients have found that they benefit from exchanging the fluid from the reservoir from time to time throughout the day. The fluid that fills the lens-cornea space is sterile, non-preserved normal saline or in some cases saline with a non-preserved tear substitute added when needed for improved comfort.
A proper care regimen for scleral lenses is not different from that for any other contact lens manufactured from a firm oxygen permeable material. The lenses require cleaning upon removal, soaking in a recommended solution appropriate to the material of the lens and a periodic treatment to remove protein deposits. Of course, the exact care specifications will vary from patient to patient according to the evaluation of their contact lens specialist.
Just like any lens modality, the fitting requires expertise. Many who fit and dispense contact lenses rely on boxed soft lenses for their patients. When corneae become distorted those lenses will hardly fill the need. Greater expertise is required to fit rigid corneal lenses needed for these more problematic surfaces. The decision of the corneal lens expert to move on to the world of larger lenses is not of the same magnitude as that from boxes to corneal GP lenses. The investment is more a matter of time spent in discussion with the manufacturer’s fitting consultants, some reading, a webinar or two and keeping up to date with the lens designs that are available.
I was not among the first to use the current generation of scleral lenses, but when the opportunity knocked some years ago, I realized the importance of this form of contact lens and I believe I have positively influenced the quality of life of many of my patients.
5/28/15
Bezalel Schendowich, OD
Medical Advisory Board of the National Keratoconus Foundation
Fellow of the International Association of Contact Lens Educators
Clinical Supervisor & Specialty Contact Lens Fitter, Sha’are Zedek Medical Center, Jerusalem, Israel
Being able to see clearly is important to all of us. But it is also something we have a tendency to take for granted until we notice changes in our vision. The point of the yearly comprehensive exam is to monitor your eyes before any problems arise, and address any concerns that could affect your vision later. Here is what to expect at your next comprehensive eye exam.
An eye exam involves an external examination of your eyes followed by a series of tests designed to evaluate your vision and check for eye diseases. Each test evaluates a different aspect of your vision and includes specific tests for visual acuity, pupil function, muscle function, visual fields, eye pressure and viewing the back of the eye through a dilated pupil.
External Exam
The external examination consists of inspecting the eyelids, surrounding tissues and the eyeball including the sclera (white part of the eye), iris and cornea.
Visual Acuity & Fields
Visual acuity is your eye’s ability to detect fine details and see an in-focus image at a certain distance. A Snellen chart and a phoropter are used. The standard definition of normal visual acuity is 20/20. The term 20/20 comes from even sized objects that can be seen by a “person of normal vision” at
the specified distance. For example, if a person can see at a distance of 20 feet an object that normally can be seen at 20 feet, then they have 20/20 vision. If they can see at 20 feet what a normal person can see at 40 feet, then they have 20/40 vision. For the visual acuity test each eye is tested separately to gauge your side or peripheral vision.
Pupil Function
An examination of the pupil begins with inspecting your pupils for equal size, regular shape, reaction to light, and direct and consensual reaction (meaning the pupil of one eye constricts when the other eye is exposed to light).
Eye Muscle Function
Eye movement is assessed two ways. First by having you move your eye quickly to a target at the far right, left, top and bottom. Then by slow tracking which uses the ‘follow my finger’ test, which tests all the muscles that move your eye.
Eye Pressure Measurement
Intraocular pressure, or IOP, is measured using a tonometer to determine the fluid pressure inside your eye. This test provides information regarding your potential for glaucoma.
Viewing the Back of the Eye
Increasing the size of your pupil with eye drops (known as dilating your eyes) allows the doctor to have a larger view of the back of your eye, including the retina, as demonstrated by this diagram. This is very important for diagnosis and tracking of macular degeneration and diabetic retinopathy.
Eye Structure
A special, high-powered microscope, called a slit-lamp, is used to view the structures of your eye clearly and in detail, enabling early diagnosis of a variety of eye conditions such as cataracts, presbyopia and corneal injury.
Taking care of your eyes, especially as you become older, is very important. Changes in vision may be gradual, or fast, but in both cases, early diagnosis is key to successful treatment and retaining your vision. It is suggested that individuals 40 and over have a comprehensive eye exam every one to two years. Exceptions would be if you have diabetes, in which case you should see your eye doctor yearly; or there is a family history of eye diseases such as glaucoma, macular degeneration, or corneal diseases, which may require more frequent visits to your eye doctor. If you have any degree of sudden vision loss, eye pain, or significant irritation, contact your eye doctor immediately.
4/23/15
Susan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation
Women account for 53% of the world’s population. However, 2/3 of the blind and visually impaired people in the world are women. While 80% of these women are in developing countries, women in developed countries like the US are still more likely to face vision loss than men.
Women are the caregivers in families, taking care of the health of family members over themselves. In addition, with many having jobs outside the home, they don’t feel they have the time to go to the doctor until something major happens, especially related to vision.
Women live longer than men are at greater risk for age-related eye diseases such as age-related macular degeneration (AMD), diabetic retinopathy, glaucoma and cataracts.
Women are more likely to develop several autoimmune diseases that can affect their eyes including, multiple sclerosis, lupus, rheumatoid arthritis and Sj?gren’s syndrome.
75% of new breast cancer diagnosed each year is estrogen-sensitive. A common part of estrogen-sensitive breast cancer treatment includes the prescription of tamoxifen. More studies are being done, but cataracts due to tamoxifen have been identified in about 10% of the patients taking the drug.
Know your family history as genetics play and important role in your eye health, so know what eye diseases run in your family. Let your eye doctor know so he can look for early warning signs that can help prevent of lessen the conditions in you.
Get routine comprehensive, dilated eye exams starting at the age of 40, to create a baseline for your doctor to work from. After that you can go every 2-4 years until the age of 60. At 60+ have a compressive, dilated exam every two years if you are symptom-free and low risk.
Eat healthy and exercise. It is important to maintain a healthy weight to reduce the risk of some eye diseases. Eating fresh fruits and vegetables is also important as they can contain carotenoids an some antioxidants that appear to help with vision retention. It should also be noted that in many studies, supplements did not show the same beneficial effects as whole foods.
Stop smoking! You not only increase your risk for cancer and heart disease, but smoking is the only thing besides advancing age that has been proven to be directly related to AMD.
Avoid ultraviolet light by wearing sunglasses (with wide-brimmed hats) and indoor glasses with UV protection. While everyone knows the sun is a source of UV light, so are electronic screens such as your TV, computer, tablet or smartphone. Prescription glasses and readers can have a clear UV coating put on them that will not distort your color vision. If you don’t need vision correction, there is eyewear with no correction that is coated to protect your eyes to avoid dry eye and retinal damage.
Use cosmetics and contacts safely. Always wash your hands first. Throw away old makeup and lens solutions. Do not share cosmetics or apply while driving. Make sure to clean your lenses thoroughly before putting them in your eyes.
Because women are relied upon to take care of the family, vision loss that can impact that responsibility can be devastating to the entire family. And later in life, when they may have outlived a spouse, the isolation and depression can destroy their quality of life as they try to cope on their own.
Reach out to women you know and remind them to take an active part in their own healthcare. Especially with regards to their vision, when women are at a higher risk of vision loss than men.
4/7/15
Susan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation
About 1.75 million U.S. residents currently have advanced age-related macular degeneration with associated vision loss, with that number expected to grow to almost 3 million by the year 2020.
About 8.4 million individuals worldwide are blind from primary open-angle glaucoma, with that number expected to grow to almost 11 million by the year 2020.
About 22 million Americans have cataracts affecting their vision, with that number expected to grow to more than 30 million by the year 2020.
The economic impact of this increase of people with vision loss will be tremendous. But right now scientist are working on ways to treat and eventually cure many eye diseases. The only problem is the funding necessary to support this sight-saving research. Here is a look at the decline of medical research funding in the US and what you can do to help.
3/17/15
Susan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation
Today technology has evolved to a point where patients either with normal refractive errors such as nearsightedness, farsightedness, astigmatism and presbyopia or those with ocular diseases that require specialized vision correction options such as those with keratoconus all have spectacular alternatives to maximize their visual performance. With the multitude of choices available, how does an individual make the decision which to take advantage of? Well let’s begin by saying that the input from your eye care professional is critically important. You need to be properly educated not only about the various options that are applicable to your individual situation but about the advantages and disadvantages of these options.
Let’s begin by discussing vision correction options available to those with normal refractive errors. Basically stated, these individuals have the ability to utilize spectacles, contact lenses or if they are appropriate candidates, consider the refractive surgical alternatives.
Glasses
Today spectacle lens technology has evolved to the point where exceptional vision quality can be achieved with lens designs that allow for the selection of almost any frame size or shape. Thin lens technologies have enabled those with high prescription powers to not only see amazingly well, but to wear glasses that remain quite thin and attractive even with some of the most extreme prescription powers. Your eye care professional can discuss the various lens material options that best work for your situation. New high index materials are not only thin but are very light weight. A concern for some however can be the significantly higher costs associated with these lens materials. For those who need multifocals, new digital and free form progressive addition lenses (PALs) have dramatically increased the success rates associated with adaptation to PALs.
Contact Lenses
Contact lens alternatives for those with normal refractive errors have also dramatically developed technologically over the past years. Today virtually every patient with normal refractive error is a candidate to wear contact lenses. Developments such as astigmatic contacts, multifocal contacts, and hybrid (rigid center / soft periphery) contact lens designs along with the introduction and the tremendous growth in the use of single use daily disposable contacts has made one form or another of contact lenses something to consider for almost everyone. Today’s CLs are healthier, more comfortable and provide better vision than ever before. CLs have the advantage of superior peripheral vision, more natural vision “sensation” and obvious advantages for demanding physical activities. With contemporary contact lens materials and designs we have successfully addressed issues that limited many people in the past such as concerns of poor comfort due to dryness, contact lens vision instability and contact lens induced complications associated with over-wear and over-use of lenses. Your eye doctor should always present contact lens options to you regardless if you ask or not. So often patients think that they can’t wear contacts, so it does become the responsibility of your doctor to inform and educate you about CL alternatives.
Combination of Glasses and Contact Lenses
So how do you decide if you should be a contact lens wearer or a glasses wearer? Who said you have to? The two vision correction options are not mutually exclusive; in fact they are quite synergistic. All contact lens wearers should have an excellent pair of glasses to use. Contacts may be more cosmetically acceptable to many, they may be much better for various physical activities such as sports, however there are many times when glasses may be preferred such as at the end of a long day of contact lens wear, first thing in the morning before inserting your CLs, or on those days you just don’t want to bother with your CLs or simply prefer the look of your glasses for some situations. Today even the person who predominantly wears glasses can consider part time contact lens wear. Single use daily disposable (DD) CLs are the perfect option for such an individual. DD CLs are now even available in astigmatism and multifocal designs!
Refractive Surgery
Refractive surgery is also developing and is more effective and safer today than ever before. An experienced and skilled eye doctor is in the best position to consult with you in order to determine if you are an excellent candidate for the various refractive surgical options available. Again, having refractive surgery does not always eliminate your need for glasses or contact lenses. Although that would be the optimal outcome, many patients still use glasses and contact lenses after having refractive surgery. Typically the glasses and contact lenses are far less strong and are used significantly less often than prior to surgery. Some patients need them due to complications of surgery while others need them when outcomes did not perfectly correct vision and of course refractive surgery does not stop eyes from changing over the years, so many patients who had successful refractive surgery may experience vision changes years after surgery that require the use of glasses, contacts or both.
Specialty Contact Lenses
Next let’s talk about choices in vision correction for those with irregular corneas and other conditions that are termed “medically necessary” vision correction cases. Individuals with irregular corneas such as those with keratoconus or post LASIK or other refractive surgery induced ectasias often require contact lenses that in essence “mask” the irregularity of the cornea. In the past this equated with the fitting of rigid corneal contact lenses, however today many other alternatives can be considered such as the fitting of scleral large diameter gas permeable contacts, hybrid CLs designed for irregular corneas and even combination systems of soft lenses with corneal gas permeable lenses (called “tandem” or “piggyback” CL systems). These CL alternatives provide advantages such as improved comfort, improved eye health response by limiting contact lens to cornea bearing, and improved contact lens positioning and stability which positively impacts visual performance.
Combination of Contact Lenses With Glasses
It should be clearly stated that spectacle lens alternatives still can have a significant role in the treatment of individuals with irregular corneas. Often glasses can be prescribed that provide adequate vision if even for part time and limited applications. While less severe cases may perform quite well with glasses as their primary modality of vision correction. Your doctor may need to modify the power of your glasses prescription in order for you to adapt to wearing glasses, however even a modified prescription power can frequently allow for some degree of visual function and allow for the ability to reduce the number of contact lens wearing hours during the day.
Surgical Procedures
Application of certain surgical and medical procedures such as intra-corneal ring segments (Intacs TM) or corneal collagen cross linking (CXL) for corneal irregularity can often help these patients in various ways and may allow for perhaps a less complex contact lens application or easier adaptation and improved function with glasses. Management of these diseases and conditions is quite complex and requires the expertise of doctors with extensive experience. Your doctor, if appropriately skilled and experienced can provide you with all of the required information and education so that you both can jointly decide on the best vision correction options for you.
In conclusion, patients today have numerous options for their vision correction. These options each have advantages and disadvantages but in most cases can be utilized synergistically. The role that your eye care professional plays in consultation and education of the vision correction alternatives applicable to you cannot be over stated. Vision is a precious gift and you should experience the highest quality of visual performance possible.
2/26/15
S. Barry Eiden, OD, FAAO
Medical Director, North Suburban Vision Consultants, Ltd.
NSCV Blog: www.nsvc.com/blog
President and Founder, International Keratoconus Academy of Eye Care Professionals
Call it a scratch, an abrasion or erosion; no matter how you describe it or what the cause, damage to the cornea most always causes pain.
So what exactly is the cornea and why can even a small scratch hurt so much? The cornea is the clear dome at the very the front of the eye. Its primary job is to surface the tears and with them, focus light into the eye. It then passes through the crystalline lens and on to the retina where it is transformed into electrical impulses that are ultimately transformed by the brain into sight.
Because vision is so essential for survival and the cornea so critical to seeing, it is among the most richly innervated and exquisitely sensitive of all tissues. Even the smallest piece of dust that finds its way into the eye and touches the cornea can cause significant discomfort, irritation and copious tearing in an attempt to wash it away. A healthy cornea is transparent and consists of several layers that give the cornea its smooth dome like shape. The outermost layer, the epithelium, is designed to break away to protect the delicate deeper layers if scratched or abraded.
The most common causes of corneal scratches are accidents. Tiny infant fingers and fingernails are a common cause of abrasions in young parents, tree branches are a frequent source of abrasions in hikers and lovers of the outdoors, and makeup brushes are a typical cause in women. Scratches can also be caused by foreign objects that get into the eye and then work their way on to the inside of the upper lid – causing a scratch that occurs with each blink. That’s why its important to carefully investigate the cause of every corneal scratch.
A scratch pr abrasion usually produces near instantaneous pain and tearing as the eye tries to wash away the irritant. Light sensitivity soon follows and can be so intense that the eye can involuntarily shut. This is actually nature’s way of “patching” the eye to facilitate healing.
To confirm you have a scratched cornea, a doctor or other health care professional will often apply a wetted fluorescein strip to the inside lid or white of the eye. Fluorescein is a dye that glows bright green when exposed to black light. The dye is absorbed by damaged areas, clearly showing the area if the scratch or abrasion.
The good news is that most scratches will rapidly heal on their own, especially smaller and more superficial ones. The confocal microscope, a high tech device that provides extreme magnification views of living tissue, has been used to observe corneal healing in real time. The video captures are breathtaking as individual corneal cells can be seen literally stretching over each other to mend and seal the corneal surface.
If an abrasion is larger or deeper it may require patching to help healing. The traditional eye patch applied with tape to keep the eye shut has largely been replaced by the bandage contact lens which is far more comfortable and allows some vision and easier observation during follow up examination. It also allows medication to be applied if needed. Because there is a risk of infection whenever the outer boundaries of the body are breached, topical antibiotics are often used as a precaution in treating scratches of the cornea and ocular surface.
Most commonly the cornea heals quickly and completely, but not always. In rare cases damaged areas of the cornea may not heal fully, leaving the outer layers of the cornea susceptible to coming off again for no apparent reason. This is thought to be more common after scratches caused by organic material such as a tree branch. Called recurrent corneal erosions, they often occur during sleep waking the person with a sudden sharp pain and excessive tearing. There are a variety of treatments for recurrent corneal erosion.
Most people will sooner or later experience a scratched cornea. Most scratches will be minor and will resolve with minimal treatment. However, some can be serious and have significant consequences. The best way to avoid problems is to be aware that they can occur and take measures to protect the eyes in situations where the risk of eye trauma is higher. This includes: wearing safety glasses while working with power tools, or sports where eye contact is possible. This includes cycling and sport shooting.
Be aware of active infants with little fingers that seem to have a magnetic attraction of their parents eyes. If you use eye makeup, leave enough time to properly apply it without rushing and potentially scratching your cornea in the process.
Finally, if you experience a scratched cornea and the pain doesn’t rapidly abate, see an eyecare specialist. Urgent care centers are fine for most things, but when it comes to the eyes finding a knowledgeable eye care professional is wise.
2/10/15
Arthur B. Epstein, OD, FAAO
co-founder of Phoenix Eye Care
and the Dry Eye Center of Arizona
Fellow of the American Academy of Optometry
American Board of Certification in Medical Optometry
Chief Medical Editor of Optometric Physician™
Ocular herpes is caused by the type 1 herpes simplex virus, and is a common, recurrent viral infection affecting the eyes. This type of herpes virus can cause inflammation and scarring of the cornea. Herpes of the eye can be transmitted through close contact with an infected person whose virus is active.
The National Eye Institute (NEI) says an estimated 400,000 Americans have experienced some form of ocular herpes, with close to 50,000 new and recurring cases occurring each year, ranging from a simple infection to a condition that can possibly cause blindness. There are several forms of eye herpes:
Treatment for eye herpes depends on where the infection is located in the eye – in the corneal epithelium, corneal stroma, or iris, etc.
Some ocular herpes treatments could aggravate the outbreak and therefore should be considered on a case-by-case basis.
If the corneal infection is only superficial, it can normally be alleviated by using antiviral eye drops or ointments, or oral antiviral pills over a two to three week period. In some patients, both drops/ointments and pills are used. Steroid drops can help decrease inflammation and prevent corneal scarring when the infection appears deeper in the corneal layers. Steroid drops are almost always used in conjunction with and simultaneously with antiviral drops. For those relatively few eyes where, despite the best of treatment, the virus has caused vision-impairing scars, corneal transplantation surgery is often a highly successful solution.
Although eye herpes has no cure, treatment can help control outbreaks. Studies are underway to determine better methods for managing the disease.
1/27/15
Susan DeRemer
Vice President of Development
Discovery Eye Foundation
