September 24, 2012
Early Glaucoma Detection Preserves Vision
By Lindsey Getz
For The Record
Vol. 24 No. 17 P. 22
Primary care physicians can play a critical role in spotting the eye disease and circumventing vision loss.
Glaucoma, which encompasses a group of eye conditions that result in damage to the optic nerve, is the second most common cause of blindness in the United States. It’s estimated that more than 2.2 million Americans have glaucoma, but only about one-half are aware of it.
Once vision is lost because of glaucoma, it can’t be regained. However, further vision loss can be prevented. And fortunately, there’s more good news in the form of new treatments on the horizon. In fact, amazing advances in medicine already have been made. The key is getting more people to visit their eye doctors and more physicians to monitor patients’ compliance with a treatment plan to protect their eyesight.
Glaucoma is a condition of increased pressure within the eyeball that can damage the optic nerve and cause gradual vision loss. When intraocular pressure (IOP) becomes elevated, there is a higher risk of developing the disease. But glaucoma is a complicated disease, and elevated IOP alone does not cause it. Other risk factors include a suspicious optic nerve as well as a genetic component.
In recent years, glaucoma research has made enormous strides, yet many Americans still experience significant vision loss or even blindness, largely due to noncompliance issues or a simple lack of prevention. According to the World Health Organization, glaucoma is the second leading cause of blindness in the world. It can strike anyone—from children to the elderly—though age does appear to be a risk factor. In addition, black Americans are six to eight times more likely to be diagnosed with glaucoma than white Americans.
The most common type of glaucoma is open-angle glaucoma, says L. Jay Katz, MD, director of glaucoma service at Wills Eye Institute in Philadelphia. “This is a very slow and insidious condition in which patients won’t be aware they have a problem because there are no recognizable symptoms until a significant amount of vision has already been lost,” he says. “It’s very important to catch these patients very early. How can we do that? The nonophthalmologist, such as the primary care physician, can play a critical role. They often look at the optic nerve as part of their routine exam. If the physician notices a difference between the two eyes or that the patient has what’s called a large ‘cup,’ then they should make sure the patient goes to see an eye doctor. It can truly be a matter of saving the patient’s vision.”
Elizabeth Muckley, OD, FAAO, director of optometric services for Northeast Ohio Eye Surgeons and a fellow of the American Academy of Optometry, agrees. “Even if there is only a family history of glaucoma, the patient needs to be referred for an eye evaluation, as there is high incidence of a genetic component to glaucoma,” she explains. “Primary care physicians can also be instrumental in checking on patient compliance with medication. They may need to ask the patient directly if they are taking any eye drops, as many patients don’t view the drops as medication even though it most certainly is. If the primary care physician notices any change in the patient’s heart rate or blood pressure and they are on a topical beta blocker, the ophthalmologist or optometrist should be contacted so that the medication might be switched.”
Innovations in Medication
Once glaucoma is diagnosed, medication or surgery may be the next option. In the past, the medications used to treat glaucoma have been eye drops that require administration three or four times per day. Physicians have found patients to be largely noncompliant with such a regimen.
“There is good data out there that shows around 30% of chronic medications are never refilled for the second prescription,” says George A. Cioffi, MD, the Edward S. Harkness Professor and chairman of the ophthalmology department at the Columbia University College of Physicians and Surgeons and the NewYork-Presbyterian Hospital/Columbia University Medical Center ophthalmologist-in-chief. “That number may go as high as 50% to 60% who have stopped medication by the end of the year. So we’re plagued with a disease that is largely silent until its late stages. Patients may feel fine for years and then go blind. There aren’t a lot of cues that urge these patients to continue taking their medication.”
Cioffi says noncompliance is even more likely in older adults. “Asking aged patients to put in eye drops may lead to noncompliance,” he says. “They often have issues that make it increasingly difficult, including limited mobility, arthritic hands, alterations in eyesight, and forgetfulness. It’s the perfect soup to produce patients who are not taking medications long-term. There needs to be a better solution.”
That solution may be on the horizon. “We have a number of compounds that lower eye pressure very well, but the problem is that patients aren’t taking them,” Cioffi says. A solution to the noncompliance dilemma may lie in the form of injectable medication, which has been called the next big advance in glaucoma research.
There also is a movement away from preservatives in eye drops. “Around 5% of patients have a severe preservative allergy, so there is a push for future medicines that are preservative free,” says Steven L. Mansberger, MD, MPH, an associate scientist and director of ophthalmic clinical trials at Devers Eye Institute in Portland, Oregon. “That will help make the drops more comfortable for the patient.”
Muckley says that with drops becoming more comfortable, compliance may improve. “Preservatives can irritate the surface of the eye and if you have dry eye, preservatives can really aggravate that dryness,” she says. “This will be a lot gentler and an excellent solution for those not able to tolerate other types of eye drops. We’re really happy to see this new technology is becoming available. We’re also happy to see that there are more generic forms of eye drops coming out which makes the medication more affordable to patients.”
Surgery and Lasers
When medication fails, laser procedures or surgery offer other options. Lasers focus internally on the drain of the eye where the fluid flows out. Laser trabeculoplasty is the procedure commonly performed and can typically be done in the physician’s office. With no cutting, the risk of bleeding and infection is eliminated.
Katz was involved in a study to determine the differences in visual fields following laser trabeculoplasty vs. the use of topical medication. Findings indicated that for the first year, the results were equal, assuming the patient remained compliant with medication usage.
“Laser can be a great option and allows patients not to worry about the drops,” Katz says. “However, cutting surgeries are typically more effective than both medication and lasers. But because you have to worry about bleeding and infection, we typically reserve that surgery for the times when medication and lasers fail.”
In the traditional “cutting surgery,” called a trabeculectomy, the surgeon creates a sclerostomy, which is a passage in the sclera for draining excess eye fluid. A flap that allows fluid to escape from the eye also is created, and the surgeon may remove a small piece of the iris so that fluid can flow backward into the eye. In a trabeculectomy, a small bubble called a bleb is formed. It’s a good sign, as it shows that fluid is draining, yet the bleb also poses risk for infection or other complications, Mansberger says.
“There are some new procedures being performed in which no bleb is formed,” Mansberger explains. “That puts patients at lower risk and may be good for patients with very high pressures and early glaucoma disease. But the downside is that it won’t lower the pressure as much as a traditional trabeculectomy; therefore it isn’t the best option for every patient.”
Also on the horizon is a new procedure called minimally invasive glaucoma surgery (MIGS), which can be combined with cataract surgery. “A lot of people in the older age group have both cataracts and glaucoma, as the risk for both goes up with age,” Katz says. “If the patient does have both conditions, MIGS can be performed with tiny instruments that add no additional risk that we know of besides the risk associated with the cataract surgery itself. We’ve found the surgery can lower pressure effectively and is an exciting development we didn’t have available five years ago.”
Monitoring and Prevention
Though there is no cure for glaucoma, if it’s caught early, it can typically be managed and eyesight can be saved. Another possible solution involves careful monitoring. For the majority of glaucoma patients, IOP plays a critical role in the progression of eyesight damage. While IOP can be measured accurately, the numbers are being recorded only every six to 12 months. “I don’t know what’s going on with the pressure in my patients’ eyes the rest of that time,” Cioffi says. “It would be helpful to know how high pressure gets in between visits. There is evidence that suggests while patients are sleeping that pressure is at its highest, but we have very little information on those times. We don’t have a good monitoring system.”
But just as patients can wear a Holter monitor in order to get a continuous recording of their electrocardiogram, researchers are looking to develop a way that eye pressure can be monitored for longer periods of time. “There have been a variety of attempts to do this in the form of indwelling sensors or in the form of contact lenses,” Cioffi says. “They’re all in the development stage, but the technology is there, and there are probably a dozen or so companies working on it in various forms.”
But even before such specialized monitoring becomes available for high-risk patients or those in the early stages of the disease, there are things patients can do now. First and foremost, timely eye exams are critical. Providers should encourage their patients to have their eyes checked regularly. Another important consideration is limiting steroid prescriptions or at least educating patients on the link between steroids and glaucoma.
“We are finding that a number of providers don’t realize that even nasal steroids and those used on the skin can lead to glaucoma when overused,” Mansberger says. “Steroids can cause elevation in eye pressure and while many providers realize this about oral steroids, they don’t always realize it’s true of those used nasally and on the skin.”
“Steroids are well recognized to raise the eye pressure in patients who are susceptible—it doesn’t happen for everyone,” Katz says. “While the pressure can go way up, the patient won’t feel any difference and will slowly go blind. Eye drops that contain steroids are the most risky, and these are occasionally prescribed for lid irritation or mild conjunctivitis. While they are prescribed for a short period of time, patients may overuse them and need to be educated to keep the use short-term. It’s also worrisome if patients are using a steroid cream directly on the eyelid for a condition like eczema. Any kind of steroid creams being used closer to the eye should be cautioned against.”
“It’s a big deal,” Cioffi adds. “The practitioner may tell the patient to use just a little bit of a steroidal face cream on their forehead and the patient is slathering it all over their face. There’s a real need for patient education.”
For any patient, a diagnosis of glaucoma is incredibly intimidating, but diligence can pay off in terms of catching and treating the condition early. And with today’s advances in medicine, the outcomes are extremely favorable. Cioffi reminds primary care physicians that by taking this condition seriously, they can play a critical role in their patients’ outcome.
“Primary care physicians need to know about the types of drugs we’re prescribing because these medications can have systemic effects and cross reactivities,” he says. “As the physician who is probably seeing the patient most often, primary care doctors need to ask about their patients’ eye health and their compliance in following through on treatment. Just taking the time to reinforce to the patient that glaucoma is a chronic disease that needs to be taken seriously can make a big difference.”
— Lindsey Getz is a freelance writer based in Royersford, Pennsylvania.
Telemedicine and Eye Disease
Experts expect telemedicine to be a key aspect of the future of medicine. Utilizing the latest technology, telemedicine describes any form of medical care delivered via communication lines using media such as the telephone, Internet, or video conferencing. Now the technology is being used in the detection of eye disease.
Steven L. Mansberger, MD, MPH, director of ophthalmic clinical trials for Devers Eye Institute in Portland, Oregon, and his team have developed a program for detecting diabetic retinopathy. “The primary care provider can order an image taken of the retina with a camera that can take photos without dilation,” Mansberger says. “Those photos are sent to us and we read them. The nice thing for the patient is that they have their diabetic eye exam right there in the primary care clinic. It takes them five to 10 minutes to get the photos taken instead of going to a separate appointment with the ophthalmologist, which many aren’t doing. If a problem is found, then they make the appointment with their ophthalmologist.”
Currently 580 patients have participated in the program, and satisfaction is extremely high among both patients and providers. “Only about 40% of diabetes patients actually go for their eye exam when the primary care physician refers them out,” Mansberger says. “But 90% follow through with our program. It’s a quick and efficient way of getting an eye exam for a diabetic patient.”
Mansberger sees a future that includes widespread use of such cameras in many primary care provider clinics. “We also detect a lot of macular degeneration, glaucoma, and other eye disease,” he says. “We can’t, however, detect if someone needs a change in their eyeglasses or if they have elevated eye pressure.”
Providers receive reimbursement for offering the photo service in their offices so there are few financial barriers. But physicians who are already pressed for time will need to figure out how to fit another service into their offerings. Mansberger says the rest is easy.
“The technology has exploded, making it very easy to send the photos anywhere in the world,” he says. “Our biggest challenge right now is to help primary care providers realize the benefits and to build it into their practice workflow.”