Ophthalmic Case Study

Ophthalmic Case Study: Beyond cataract treatment

Until fairly recently, patients with cataracts - the gradual clouding of the eye's lens - had to undergo invasive surgery, followed by several days of in-hospital recovery to correct the disorder. After the procedure, most patients still had to wear glasses or contacts to correct any other vision problem they might have. Now, because of a steady stream of technological advances, patients are treated effectively with minimally invasive techniques, and many never need glasses or contacts again.

Like so many other medical technologies, improvements in cataract treatment have been rapid and constant. But in the case of cataract surgery, the advances go beyond the treatment of cataracts. In recent years, breakthroughs developed to treat cataracts have been used to correct vision problems resulting from another very common eye disorder, presbyopia, the loss of ability to focus at close distances.

Perhaps the most unexpected outcome of these technological advances and their wider application is this: patients who undergo the lens exchange procedure to correct presbyopia, hyperopia, and myopia will never develop cataracts. In other words, in the course of developing the most cutting edge treatment for cataracts, researchers and physicians have discovered a route to prevent the onset of the disease in the first place.

Technology comes full circle

Jean Henderson is a perfect illustration of how these leaps in technology have been applied. Like millions of Americans, Henderson started having trouble with her short range vision - seeing print in books and magazines for example - when she was in her mid-40s. Henderson's sight problem, caused by presbyopia, improved with bifocals. But the condition worsened and by the time Henderson, a special education teacher in Pearland, Texas, reached her mid-50s, she was wearing trifocals to correct her distant, intermediate and near vision.

Though glasses helped improve Henderson's distant and close range vision, there was a noticeable delay as her eyes adjusted to shorter distances. When she looked at the board or read text along with a student, she says it seemed to take a second or two to find the right part of her glasses for viewing words clearly. That lag was obvious to Henderson and to her students, she says.

Henderson's condition also made climbing stairs, driving a car, and finding her way around new surroundings difficult and intimidating. That meant she rarely went anywhere but work and church.

After struggling with her sight for nearly a decade, Henderson underwent a revolutionary surgical procedure to correct the problem. The procedure combines the dramatic advances made in cataract surgery in the last three decades with a highly advanced artificial lens.

Although Henderson did not have a cataract, the same technique was used to treat her hyperopia and presbyopia. In less than half an hour, with just topical eye drop anesthesia, the natural lens in Henderson's right eye was removed and replaced with an artificial lens that allows her to see clearly, without glasses, at far, intermediate and near distances. The procedure was perhaps even more significant for Henderson than most other patients because she has amblyopia in her other eye and the vision in this eye is not entirely normal and cannot be fully corrected, even with surgery.

The benefits of the procedure go far beyond permanently correcting Henderson's vision. The eye in which her artificial lens was implanted will never be vulnerable to cataracts - the clouding of the lens that affects 20 million Americans today and is expected to affect more than 30 million by 2020.¹ In other words, the procedure she underwent could be considered a vision correction/cataract prevention procedure.

That means neither Henderson, nor Medicare, which spends billions of dollars on cataract surgery each year, will ever face the possibility or the cost of cataract surgery for her corrected eye. As more Americans choose to undergo lens exchange procedures to correct their vision, the potential for developing cataracts, and the costs associated with them, drops.

Saving the capsule

While lens exchange surgery prevents cataracts in patients, the outlook for patients who have or will develop cataracts has never been better. New technologies are responsible for dramatically improving outcomes for cataract patients. Surgery time is shorter, recovery time is faster and vision is better after today's cataract procedures.

Once a cataract develops, the lens has to be extracted; the cloudiness cannot be removed without removing the entire lens. The most difficult part of a cataract procedure, even today experts say, is removing the lens without damaging the capsule, the clear sac in which the lens is housed.

Traditionally, in patients with cataracts the procedure involved making a nearly 180º incision around the cornea to access and extract the entire clouded lens. "We had to suture it all back together, which often created a lot of astigmatism," says Dr. Guy Knolle, the Austin, Texas, ophthalmologist who implanted the new lens in Henderson's right eye. In addition, the large incision and removal of the entire clouded lens within its capsule resulted in the loss of the best possible location for a new lens. Surgeons now understand that there are several adequate locations for the new lens, but the patient's original capsule is the very best location to support the artificial, intraocular lens (IOL).

Most ophthalmologists, including Knolle, say the revolution in cataract surgery began in the late 1960s when a physician named Charles D. Kelman began developing a procedure using ultrasonic pulses to remove the lens without also removing the capsule. Kelman's procedure was groundbreaking because it allowed removal of the clouded lens through a much smaller incision. Over the years, others have improved on Kelman's technology and now surgeons can perform cataract surgery through an incision that is three millimeters or less in length.

"We came from doing large incision cataract surgery and trying to get the patient to wear glasses that magnified his or her whole world by 30 percent, to a small incision cataract procedure that left enough of the capsule behind to support the intraocular lens," says Knolle. Placing an IOL within the capsule provides greater stability and centering than any other location.

Once small incision cataract surgery was introduced, improvements in cataract treatment came non-stop. Knolle says the next huge leap in cataract care came with the introduction of foldable intraocular lenses in the mid- to late-1980s. "The foldable lens allows us to utilize a three millimeter incision without having to enlarge it. Before that, we had to enlarge it, to six millimeters or more to insert the lens," he says.

Ophthamologists prefer to work with very small incisions, which give them more control of the eye. Smaller incisions also minimize the amount of fluid that exits the eye during the procedure. During the initial, most difficult part of the procedure, the removal of the cloudy lens, they keep the incision at three millimeters. Only after the cataract lens was extracted did surgeons expand the incision to implant the IOL. Now, with foldable lenses, enlarging the incision is unnecessary.

Devices used to insert IOLs into the capsule have also improved the procedure. These devices allow the surgeon to fold an IOL and place it in a loading chamber. When activated, the insertion device slowly injects the lens into the capsule. "As it comes out of the loading chamber, it spontaneously unfolds and it wedges itself into the capsule, like you wedge yourself in a door jamb with your elbows," Knolle explains.

No sutures are necessary with this procedure, Knolle says. "Once the lens is in place, then we close the incision by injecting balanced salt solution into the edges of this incision. The incision is a flap valve-type incision that's beveled, so the higher the pressure in the eye, the tighter the closure," he explains.

Better lenses, better vision, lower costs

Clearly, the procedure used to extract lenses and replace them with IOLs has improved remarkably over the last couple of decades. At the same, artificial lenses have also undergone major enhancements.

Knolle says lenses are available to correct refractive problems - which cause blurred vision at various distances. "Now we do surgery for people who are far sighted or near sighted," says Knolle. The lens he usually implants allows patients to see clearly at a range of distances, including near, middle and far.

Cataract patients benefit from these advances as well, since they can be implanted with lenses that allow them to see at a variety of distances, eliminating their dependence on glasses or contacts. Knolle has been implanting a multifocal lens since 2000. "I've done over 600 operations with it. I almost never use the monofocal lens anymore because it doesn't give patients the depth of field provided by multifocal lenses," he says.

Lens implants are also constantly being enhanced with features that improve the overall health of the eye. For example, many artificial lenses have filters that can block certain harmful rays of light. Some lenses filter ultra violet light-a widely recognized culprit in another devastating eye disorder, age-related macular degeneration-for example.

In addition to the huge potential savings for Medicare from the prevention of cataracts and age-related macular degeneration, improvements in treatment have yielded millions of dollars in immediate savings to the government health program for the elderly by reducing the recovery period, eliminating the need for an overnight hospital stay and reducing the complications that require further medical intervention.

Beyond savings to Medicare, successful cataract surgery results in improved economic output from employees. According to one study, cataract patients contributed $95,000 more in economic productivity from improved quality of life than if they had not had the surgery. ²

Just in time

Advances in cataract care, as well as those introduced to treat other age-related eye disorders, come just as America's Baby Boom generation is reaching the critical age for developing these diseases. While cataracts are the most prevalent disorder, and will be in the coming years, other eye disorders are expected to affect tens of millions of Americans. Advances in medical technology have kept pace with these diseases as well.

Age-related macular degeneration occurs when the small central portion of the retina called the macula is damaged. It is estimated the 13 millions Americans now suffer from AMD, with that number growing to nearly 21 million by 2020.³ While there is still no cure for this condition, laser therapy can stop further deterioration of a patient's vision.

Two types of laser treatment are used to combat AMD. In traditional laser therapy, high-energy lights are used to destroy actively growing abnormal blood vessels that occur in macular degeneration. In photodynamic laser therapy, a light sensitive chemical is injected into the bloodstream and absorbed by the abnormal blood vessels in the eye. The doctor then shines a cold laser into the eye to activate the drug, damaging the abnormal blood vessels.

In addition, researchers are working on an experimental surgical technique that involves rotating the part of the retina which is not attached to the optic nerve, allowing the portion of the macular that is still healthy to rest over healthy blood vessels.

Glaucoma is a group of eye diseases that threaten vision loss because of damage to the optic nerve. More than two million Americans have glaucoma today; 3.3 million are expected to suffer from it by 2020. Damage usually occurs because of blockage of the eye's drainage canals. In addition to medications used to treat glaucoma, advances in laser surgery have allowed physicians to create or expand the tiny openings needed for eyes to drain fluid properly, relieving pressure inside the eye that could damage the optic nerve.

Diabetic retinopathy occurs when diabetes damages the tiny blood vessels in the retina. Eventually, the damaged blood vessels can leak and cause swelling and damage to the retina. The growing incidence of diabetes among Americans has experts concerned that the prevalence of this disease could be enormous in coming years. Today, 4.1 million Americans have it; by 2020, that number is expected to rise to 7.2 million.

While diabetic retinopathy cannot be cured, it can be treated to minimize the impact on the patient's vision. Laser surgery has been used to seal broken blood vessels and prevent further leakage. In severe cases, laser surgery can be used to destroy large groups of abnormal blood vessels. In cases where the patient has significant amount of blood clouding the fluid inside the eye, surgeons can perform vitrectomy, which involves removing the cloudy fluid and replacing it with a salt solution.

With these and other innovations on the horizon, the future for patients with age-related eye disorders has never been brighter.

For more information on cataract technology innovations, see AdvaMed’s news release: Cataract Awareness Month: Advanced Procedure Correct Vision, Prevents Onset of Cataracts.

¹ National Eye Institute, National Institutes of Health
² "Is Technological Change in Medicine Worth It?" David M. Cutler, PhD and Mark McClellan, MD, PhD, Health Affairs, September/October 2001.
³ National Eye Institute, National Institutes of Health.