The Post interviewed Dr. Ronald Krueger of the Cleveland Clinic Cole Eye Institute—a veteran of 18,000 refractive surgery procedures—about why vision sometimes gets worse after LASIK and how to avoid or treat this perplexing post-op problem.

To frame the discussion, however, let’s first take a quick look at the eye, specifically its outmost covering, the cornea, which provides two-thirds of the eye’s focusing power.

How well you see depends on the shape and curve of your cornea. A normal cornea is smoothly rounded with even curves from side to side and top to bottom. Vision problems—or refractive errors—affecting about 120 million people in the United States develop when the cornea becomes too curved (nearsightedness), too flat (farsightedness), or curves more in one direction than in another like the back of a spoon (astigmatism).

Eyeglasses and contacts correct refractive errors, but LASIK surgery is an increasingly popular option for convenience and comfort.

So, here’s the rub.

During LASIK, the surgeon creates a flap in the eye’s cornea and then uses a laser to reshape it for good vision correction, explains Dr. Kreuger. In a relatively few cases, the cornea weakens after surgery (a condition called ectasia) and loses its ability to maintain the desired shape. As a result, vision blurs and gradually deteriorates.

We asked Dr. Krueger to discuss the latest information about the symptoms and risks for post-LASIK ectasia, and new advances in what doctors can do when it occurs.

Post: What are the symptoms of post-LASIK ectasia?

Dr. Krueger: Patients with ectasia lose visual acuity—some immediately, others months or even years after the surgery. Images become distorted as the cornea loses its rounded shape, and most find they need new lenses or progressive glasses as those changes occur.

Post: How common is it?

Dr. Krueger: Post-LASIK ectasia parallels keratoconus, a naturally occurring condition in which, although no surgery has taken place, the structural integrity of the cornea is not maintained and begins to bulge in certain ways that distort vision. Probably one out of 2,000 people in the population have keratoconus.

LASIK-induced ectasia, while rare, is presumed to be more prevalent in people with subclinical keratoconus. In other words, patients with previously unrecognized corneal weakening may develop a more prominent problem after LASIK.

Post: Who is most at risk?

The most common risk factor is an irregularity on the corneal topography map, a tool we utilize to help screen out individuals who are not suitable candidates for LASIK surgery. As mentioned, having an irregular or steep cornea may be a telltale sign of subclinical keratoconus that may contribute to post-operative ectasia.

Surgeons also look very carefully at a risk score system that is based on published data collected over many years from large groups of patients who developed post-LASIK ectasia. In developing this system, investigators assigned a certain amount of risk to various factors. For example, corneal thickness less than A amount might have B amount of risk toward ectasia. A topography map showing C amount of irregularity may contribute D amount of risk. Being young presents more risk because the cornea gets a little stiffer with age. Then, they developed a way to tabulate an overall score from the list of individual risks.

While the scoring system is published and based on actual data, it has been criticized. Many patients who fit or exceed that score have done perfectly fine and never developed ectasia. But LASIK surgeons do consider this score before doing surgery in order to avoid this phenomenon.

Post: Are topography maps standard of care in LASIK surgery?

Dr. Kreuger: Yes. But they aren’t definitive. Surgeons have to consider other factors.

Post: Does ectasia usually show up in both eyes?

Dr. Kreuger: It can initially develop in one eye, but the potential could exist in both eyes.

Post: What can be done to help people with post-LASIK ectasia?

Dr. Kreuger: The primary treatment is contact lenses to provide a new, smooth shape for the eye to look through.

What has come along for keratoconus, and is showing benefit for post-LASIK ectasia, is a procedure called crosslinking. Collagen crosslinking is a photochemical method of applying vitamin B-2 (riboflavin) drops on the eye and then shining an ultraviolet light that activates the riboflavin to help create little links in the cornea that make it stronger. It is being used in countries around the world, and FDA trials are underway in the United States.

Post: So this is an experimental procedure at this point?

Dr. Kreuger: It’s an investigational procedure in the United States. But it has been investigated in other countries and has shown good success.

Post: Are corneal transplants an option?

Dr. Kreuger: In advanced cases, yes. A transplant will replace the irregular and weak cornea with a stronger one. Then, you can correct it. But that’s a pretty advanced procedure. Corneal transplants may also be considered when crosslinking is not a good option or has been tried and is not fully correcting the problem.

Post: What advice would you offer to people considering LASIK?

Dr. Kreuger: I would suggest several things: 1) Go to more than one place to have your eyes evaluated so that you can get a sense of what doctors are saying at one place versus another. 2) Do some homework so you can ask lots of questions. 3) Make sure you are going to a place that has a stellar reputation for eye care in general. 4) Find an experienced doctor who has good judgment and the patient’s best interests at heart. 5) Ultimately, find the latest technology. Sophisticated imaging devices are now available to help determine which eyes have any risk for keratoconus or ectasia. Hopefully, there will be even newer and better tools in the future.

When LASIK Surgery Goes Awry The Saturday Evening Post

Sherman
Illinois

A coloboma is a “hole” or defect in one part of the eye that occurs before birth. Depending on location and size, it may lead to mild or severe effects on vision.

Ophthalmic surgeon and spokesperson for the American Academy of Ophthalmology Dr. James Salz comments:

“You probably have a coloboma of the iris, which is the colored part of the eye. This means that a portion of the iris did not close around the pupil as the eye developed. As a result, the pupil is shaped like a keyhole rather than a circle. People with colobomas of the iris are suitable candidates for cataract surgery—and so are older individuals. Ask for a referral to a cataract surgeon from your medical doctor if you do not already have an eye doctor.”

Eye Defect & Surgery The Saturday Evening Post

Our eyes change over time, and the challenges to our eye health shift, too. People in their 20s and 30s may begin wearing eyeglasses or need a different eyeglass prescription. For those in their 40s, reading glasses and problems with dry eye—which may disproportionately affect women due to hormonal changes related to the approach of menopause—are common realities. And, double or blurred vision and sensitivity to light may signal the early onset of cataracts and make activities such as driving at night difficult for individuals over 50.

To promote optimal eye health for life:

Get regular eye exams: Many women (and some men, as well) are so busy taking care of families that they forget about their own health and wellness. Take the first step. Schedule an annual exam to help detect the five major threats to eye health, including glaucoma, cataracts, dry eye, diabetic retinopathy, and macular degeneration.

Eat for your eyesight: Plan ahead to eat plenty of berries, two daily servings of leafy greens, two weekly servings of oily fish, and foods rich in vitamin C such like oranges and broccoli. Omega-3 fatty acids help maintain a normal tear film, which is critical for crisp vision that doesn’t fluctuate. Leafy green vegetables provide lutein and xeazanthin to help maintain the health of the macula, the part of the retina responsible for central vision. Vitamin C helps prevent changes due to aging in all of the ocular tissues.

Stay safe in the shade: Whatever the season, always wear a hat, sunglasses, or shades when outdoors. Exposure to bright sunlight may increase the risk of developing cataracts or age-related macular degeneration.

Make exercise part of your day: Being overweight increases your risk of diabetes, hypertension, and high cholesterol—conditions that may harm the retina and result in vision loss.

Maintain healthy tears: Tears nourish and protect the eye surface from excessive dryness that can lead to impaired vision and increased risk of infection. To help ease dryness, itching, and irritation, opt for over-the-counter artificial tear products (e.g., Optive, Refresh, or Fresh Kote). Chronic use of eye whitening drops (e.g., Visine or Naphcon-A) may actually worsen eye dryness. Talk to your eye doctor if using artificial tears becomes routine. In some cases, prescription eye drops (e.g., Restasis) may be beneficial.

Preventing Macular Degeneration with Greens

Five Strategies to Save Your Sight The Saturday Evening Post

I have been going to an ophthalmologist every six months for two years. I go every six months because I’m prone to having glaucoma. At my last visit, the doctor said my eye pressure is fine so far but that I have a rare form of glaucoma. He said narrow angle, but I didn’t ask if it was the acute kind or another form.

Could you explain the different forms? Do I need to watch more carefully for certain signs and symptoms, and how dangerous is narrow angle? Could I go blind quickly if I don’t get help right off?

Gail

We sent your letter to Indiana University glaucoma expert Dr. Darrell WuDunn. He explains:

“The angle that is narrow in your condition refers to the area through which the fluid in the eye drains out. Different forms of glaucoma are based on the configuration of this angle. Open-angle glaucoma is the most common form in the USA. In angle-closure glaucoma, the iris, or colored part of the eye, blocks fluid drainage and causes elevated eye pressure. Having narrow angles does increase the risk of developing angle closure glaucoma. This can happen abruptly in an acute angle-closure attack, or it can occur more insidiously in chronic angle-closure glaucoma. In either condition, damage to the vision can occur. When acute angle-closure develops, you may experience severe eye pain, redness, blurred vision, seeing haloes around lights, and even nausea and vomiting. If these symptoms occur, you should seek emergency treatment to prevent or minimize vision loss. Permanent vision loss or blindness can occur within hours during an acute angle-closure attack. If you have particularly narrow angles, an ophthalmologist may recommend a laser procedure to widen the angle and thereby decrease the risk of angle-closure glaucoma. Regular monitoring of your condition is also important.”

Types of Glaucoma The Saturday Evening Post

I had a cataract implant in the early ‘80s and now am having failing eyesight. My doctor says to remove the implant will require a cornea transplant.

I am hoping that you know of a better way to remove and replace the lens. Thank you for any help you can give.

We assume that you have an intraocular lens, or IOL, implant. In general, an artificial lens implant is considered permanent. It remains transparent and does not move or wear out over time.

On occasion, some people may experience clouding of the tissue that holds the artificial lens in place. In these cases, laser therapy may help restore clear vision.

Good eyesight also depends on a healthy retina and optic nerve. Diseases such as macular degeneration or uncontrolled glaucoma may damage these delicate eye structures and cause vision problems. Regular dilated eye exams by an ophthalmologist are vital. People with diabetes have a high risk of vision problems and need to be especially vigilant. For more information on diabetic eye disease, call Prevent Blindness at 1-800-331-2020 or visit www.diabetes-sight.org.

Fight for Sight The Saturday Evening Post

Indiana University ophthalmologist and surgeon Dr. Darrell WuDunn responds:

“I, as well as other glaucoma specialists, have inserted and removed these devices. However, the more relevant question is whether removing the Ahmed Valve will relieve the tearing. These devices do not typically cause tearing, and other eye conditions, such as ocular surface disease or eyelid abnormalities, are more likely to blame. If the eye no longer sees, then it may be undergoing changes such as surface calcification or shrinkage of the globe. These conditions should be excluded as the cause of the tearing before considering removal of the Ahmed Valve. Your eye surgeon should be able to make an assessment of the cause of the tearing and recommend, or refer you for, the necessary care.”

Persistent Tearing The Saturday Evening Post

While vitamins can’t cure age-related macular degeneration (AMD), research suggests that eating plenty of fish, green leafy vegetables, and fruits may delay its progression and preserve vision. See below for a list of potentially sight-saving nutrients in foods and supplements.

Most people with macular degeneration have the “dry” form of the disease. It is characterized by the gradual breakdown of cells in the macula, the part of the eye responsible for detailed vision. In “wet” AMD, abnormal blood vessels damage the macula—disrupting vision in the process. Laser and drug therapies to eliminate the extra vessels may allow patients to see more clearly.

Periodic dilated eye exams help ophthalmologists and their patients monitor symptoms and make treatment decisions. Getting regular exercise, maintaining normal blood pressure and weight, and not smoking are also important. In the future, scientists hope that advances with stem cells and genes will prevent or cure the disease.

Data from the Age-Related Eye Disease Study show that taking the following supplements reduced the risk of vision loss in some people with intermediate or advanced AMD:

• 500 mg vitamin C
• 400 IU vitamin E
• 15 mg beta carotene
• 80 mg zinc (as zinc oxide)
• 2 mg copper (as cupric oxide)

More recent studies show that adding lutein and zeaxanthin to the diet may also reduce the risk of developing advanced AMD. These carotenoids are found in the macula. Food sources include Brussels sprouts, spinach, broccoli, kale, and greens.

Medical Mailbox supplements the advice of your healthcare provider, whom you should consult for personal medical problems.

Aging Eyes The Saturday Evening Post

I had a driver’s permit before moving to Iowa. Here they have a questionnaire for an optometrist or ophthalmologist to fill out. Years ago, an optometrist told me that he had done all he could do for my vision. What does an ophthalmologist do?

E.

An ophthalmologist is a physician who treats eye conditions and diseases with medicines and surgery. Some ophthalmologists learn to care for children’s eyes, perform corneal transplants, or do plastic surgery. In most states, an optometrist or Doctor of Optometry (O.D.) diagnoses but doesn’t treat eye diseases. Many provide low vision rehabilitation and perform minor surgeries. Both types of eye specialists are trained to examine the eye, diagnose eye diseases, and prescribe glasses and contact lenses.

Each state passes its own laws about the requirements necessary to obtain and renew a driver’s license.

Eye Experts Have Different Training The Saturday Evening Post