Dry Eye Practice: Bursting with Potential

Ever-present but often overlooked, dry eye patients have the power to transform your practice. Here's how to harness what's beneath the surface.

BY RENÉ LUTHE, SENIOR ASSOCIATE EDITOR

Glance at your appointment book for the week and you'll likely see a schedule packed with cataract patients, glaucoma follow-ups and early-onset retinal disease — the stock in trade of a comprehensive ophthalmologist. But look beneath the surface and you'll find that very many of these patients also suffer from dry eye in some form, often with an impact on quality of life rivaling that of their chief complaint.

Ophthalmologists who dismiss dry eye as a "lesser" condition shortchange their patients and their practice. A more robust approach is needed, dry eye experts caution, as the condition is certain to become more prevalent and make its impact felt not only in patients' day-to-day lives but in surgical outcomes as well. Below, dry eye experts offer their insights for recognizing and managing a problem that is very likely already in your waiting room.

For a condition that has been widespread for years now, there appears to be a lot that clinicians still don't understand about dry eye. In fact, "the more we learn about dry eye, the more we realize what we didn't and do not know," says James P. McCulley, MD, professor and chair of ophthalmology at University of Texas Southwestern Medical School in Dallas. Often, the biggest challenge is simply identifying patients afflicted by it, and giving the condition its due.

It Matters to Patients

Dry eye affects approximately 15% of the US population, according to Francis S. Mah, MD, of the University of Pittsburgh School of Medicine. Yet many clinicians believe that dry eye is still often under- or misdiagnosed. "I think doctors don't realize how prevalent it is," says Stephen C. Pflugfelder MD, of Houston's Baylor College of Medicine.

Johnny L. Gayton, MD, of Warner Robins, Ga., agrees, calling dry eye the most common diagnosis made in his practice. "It never ceases to amaze me how many people I see come in who have a sack full of potions that they've been prescribed," he says. "They'll have a nonsteroidal, a steroid, an antibiotic-steroid, an allergy drop — and their primary condition is dry eye syndrome that's been missed."

The condition has an impact on patients' quality of life that many clinicians still fail to grasp, according to some experts. Those slow on the uptake, though, have found that their patients are eager to fill them in on what life with dry eye is really like.

Broach the subject with patients and you're likely to get a torrent of information in return. "Our patients are telling us, ‘You may think I see well in this controlled environment [your exam lane], but at the end of the day, when I'm driving home in December, and I've been on a computer all day long with the ceiling fan going and, by the way, I'm on one antidepressant and three medications for blood pressure, I have glare, halo and I just can't see, and things are on top of each other,’" says Shachar Tauber, MD, director of ophthalmology research at St. John's Hospital and Clinics in Springfield, Mo.

Venting of that sort should be seen as a call to arms, as it signals an unmet patient care need that requires your attention. Such patients are supported in their complaints by a 2003 study in which patients rated dry eye's impact on their quality of life as comparable to that of cardiac angina.¹

Under- and Misdiagnosed

As for the reasons that dry eye still can often elude clinicians, experts say they range from the syndrome's common symptoms to an absence of careful screening to physicians' sometimes dismissive attitude about a problem that doesn't affect vision and that doesn't involve surgery.

"When I was going through medical school, they used to call syphilis the great imitator," given its ability to present in so many different ways, explains Dr. Gayton. "Well, the same thing holds true for dry eyes."

Its varied and common symptoms mean that it can imitate infection, which commonly accompanies it; similarly, it can either imitate allergy or present concurrently with it. Additionally, Dr. Gayton explains, some patients will exhibit contrary symptoms. "Some people will come in, and their eyes will look like the Sahara desert. And you'll have other people come in, and their eyes are pouring water. But both have dry eye syndrome!"

Dr. McCulley cites the complexity of dry eye as the reason it often evades satisfactory treatment. "It's a lot more complicated constellation of signs and symptoms, underlying etiologies and pathophysiologic mechanisms that often interact and cascade than we ever appreciated before," he says.

Dr. Pflugfelder points out that the absence of a standardized method for detecting dry eye means that many eyecare practices do not screen for it adequately.

Additionally, Dr. Mah claims, some clinicians neglect to consider the possibility of blepharitis or the eyelid component in their patients. Instead, he says, the impulse is often to simply give any patient complaining of itchy, dry eyes an artificial tear.

Diagnostic Difficulties

That lack of a standardized method of diagnosis is a common complaint among the dry eye experts Ophthalmology Management spoke with. "Part of the major problem in diagnosing dry eyes is that there is no one specific test that is conclusive for the diagnosis, but rather a battery of tests that we use, all of which, taken on their own, are inconclusive," explains Henry D. Perry, MD, of Cornell University in New York.

Dr. Mah concurs. "For cholesterol, doctors give patients a blood test and can say, ‘Okay, you've got high cholesterol because this number is high.’ There's no dry eye test where you can say, ‘You have dry eyes because this test is positive or negative.’ Instead, we do every test we have and we also have to take into consideration the symptoms." Only then can the doctor make a diagnosis of dry eye.

Dr. McCulley points out that many ophthalmologists use only fluorescein staining, but that that has its limitations. "That's going to allow one to see the dry spots on the cornea, but the sequence of development of dry spots is first the nasal interpalpebral fissure conjunctiva, then the temporal interpalpebral fissure conjunctiva, and finally the cornea," Dr. McCulley explains. "The less severe dry eyes are better diagnosed with the use of vital stains that will allow us to see the dry spots on the conjunctiva before the disease has gotten so severe as to affect the cornea." Because he finds the tear break-up time test to yield relatively nonspecific results and other factors can affect tear break-up time, his preferred diagnostic test is vital staining on the ocular surface.

Dr. Pflugfelder names patient complaints as his preferred method of detection. Beyond that, he favors tear break-up time and dye staining — fluorescein staining for the cornea and lissamine green for the conjunctiva. Increasingly, he says, he relies on corneal topography to examine the smoothness of the epithelium, particularly in patients who are considering surgery.

Dr. Tauber also favors fluorescein and lissamine green staining. Additionally, he examines the tear lake.

"The height of the tear lake is very simple to look at in the slit lamp," he says. "We look at the status of the lids themselves. It's important to squeeze the lower lid and see if you can get a toothpaste-type of response, or are you getting actual oil coming out? If you get a buttery type exudate, like toothpaste coming out, you know that's disturbing the tear film and that patient is going to have decreased quality of vision." He adds that the tear break-up time is a good way to determine that as well.

Dr. Mah adds that a "really complete eye exam" must be part of the diagnostic process in order to rule out eyelid disease, meibomian gland dysfunction or other issues. Also essential, he says, is a thorough conversation with the patient. "Probably more than half the diagnosis is made from just talking with the patient and getting symptoms."

Treat the Cause, Not (Just) the Symptoms

Yet another problem with diagnosing dry eye, according to the University of Chicago's Mitchell Jackson, MD, is that "doctors don't really understand the cause of dry eye — it's as basic as that."

While lubricating drops are very helpful in treating the symptoms of dry eye, Dr. Jackson says, there will be no real success in therapy until the cause is addressed. "My analogy in these situations is, if somebody had a stroke and is put on a blood thinner, would you leave untreated the high blood pressure that caused the stroke?"

Dr. Jackson prescribes cyclosporine to patients with autoimmune disease because it treats dry eye at the lacrimal gland level. Other causes, he emphasizes, would receive other treatments. Lid disease, which might precipitate a lipid layer cause of dry eye, must also be considered, he says.

Dr. Mah concurs, saying that in his experience many clinicians don't look at blepharitis or the eyelid component. Instead, he says, they often just tell the patient to use artificial tears and to return if they don't work.

"Even when doctors prescribe Restasis, often they don't consider other compounding issues, such as blepharitis or the meibomian gland condition," Dr. Mah says. "Or further inflammatory conditions, or neurotrophic issues. They just treat every patient as if they've got an aqueous component — they just don't have enough tears, so use the artificial tears, use Restasis."

If that strategy doesn't take care of the problem, Dr. Mah says, the physician may decide the patient has some other problem and refer him or her out. Or simply dismiss the patient as a complainer.

Dr. Jackson cautions that the cause of a particular patient's dry eye could be multifactorial. "It could be deficiency at the aqueous layer, it could be a lipid layer deficiency, or could involve the mucin layer, which is a goblet cell problem." He also advises careful consideration of potential systemic causes.

The Drug Connection

Another factor to consider and discuss with patients before determining a therapy is the medications the patient may be taking. "Tons" of medications have side effects that could cause or exacerbate dry eye, according to Dr. Jackson. These include antihistamines, blood pressure and heart medications, diuretics and asthma drugs. Simply switching medications or, for instance, taking an antihistamine only when necessary, may resolve the patient's dry eye.

Glaucoma medications seem to be linked to dry eye symptoms as well, warns Peter Libre, MD, of Connecticut Glaucoma Associates in Norwalk. He says that most glaucoma medications contribute to corneal epitheliitis, a keratitis which has "symptoms and signs indistinguishable from dry eye syndrome." He attributes this to a combination of epithelial toxicity of medications and preservatives, as well as pharmacologic effects on the lacrimal gland, goblet cells and meibomian glands.

The prevalence of dry eye in glaucoma patients has led Dr. Libre to conclude that glaucoma medications may cause cumulative damage to the ocular surface. The damage appears to be related to the number the drops the patient has taken over span of their treatment regimen. In these cases, Dr. Libre says, lubricating drops and even cyclosporine provide little relief.

"A very important principle is to prescribe the fewest possible number of drops daily," Dr. Libre explains. "I generally advise selective laser trabeculoplasty as initial therapy." He usually prescribes prostaglandins on an every-other-day schedule. "I rarely find that four medications yields a lower IOP than three, so I typically prescribe every-other-day prostaglandin."

Determining Therapy

Once you're confident of the diagnosis and its cause, twists and turns still remain in selecting a therapy — or therapies. According to Dr. McCulley, determining treatment depends on multiple principles, including the initiating cause of the dry eye, the severity of the problem and how much inflammation is associated with it.

Experts agreed that a simple approach, starting with lubricating tears, is a good start to address mild dry eye — however, the drop must address the component of the tear film most likely to be involved in the dry eye, says Dr. McCulley. Newer generations of artificial tears allow the clinician to address the patient's particular tear problem and offer better relief. Evaluate the tears and select accordingly.

"You know, it's not your father's Oldsmobile anymore, as the slogan goes, nor is it your mother's artificial tear," says Dr. Tauber. "And I think we need to look at the modern tears and see that there's a difference from what Walmart puts out as a generic-type of artificial tear."

The causes of the patient's dry eye may be multiple, Dr. Jackson cautions, so lubricating drops may not be enough. If the problem is aqueous deficiency, cyclosporine should be prescribed to address that; for lid margin issues, he suggests topical azithromycin.

Dr. Gayton says he likes to start patients with an appropriate artificial tear and omega-3 supplements. He too favors azithromycin for patients with lid involvement, noting that it has been shown to improve meibomian gland function (see Figure 1) and contribute to resolution of dry eye symptoms. For patients whose dry eye still can't be controlled, he favors fluorometholone ophthalmic at night and liberal use of punctal plugs, either temporarily or permanently.

Figure 1. Dry eye patient with lid involvement before (left) and after (right) treatment with topical azithromycin for two weeks.

Consider Cyclosporine Sooner

And while many ophthalmologists do not prescribe cyclosporine until the dry eye becomes severe, these experts recommend that it be used earlier in the course of the syndrome.

Dr. Perry cites his 2008 study that demonstrated that cyclosporine worked in only about two-thirds cases of severe dry eye patients,² "whereas if you use it in cases with relatively mild disease, they will respond in more than 80% of cases," he explains. He thinks the finding mirrors the experience that physicians have in treating chronic disease elsewhere in the body. "The earlier the treatment begins, the better are the results and the more likely it is to avoid the long-term problems," says Dr. Perry.

Similarly, a study presented at the 2009 American Academy of Ophthalmology meeting by Sanjay N. Rao, MD, found that dry eye patients who were switched to an artificial-tear only treatment after one year of cyclosporine BID showed progression of dry eye disease at one year (as measured by ocular surface staining, tear break-up time and Schirmer test with anesthesia, among other measurements). Patients who continued on Restasis, however, showed improvement in disease severity.³

Some ophthalmologists prescribe cyclosporine before dry eye can even rear its ugly head. Dr. Tauber reports that he puts all LASIK patients on cyclosporine preoperatively, because it improves the tear function postoperatively.

Patient Education Pearls

"No one wants to change lifestyle," says Dr. Tauber. Nevertheless, successful treatment of dry eye often requires it. Environmental changes to improve dry eye have been covered extensively, but there are a few that bear repeating, or that you may not have heard before.

Emphasize to patients that they should not wait until their eyes feel dry and dry spots have formed before instilling their artificial tears. Dry spots tend to be selfperpetuating, Dr. McCulley points out.

"I tell them that if you wait until your eye feels scratchy before using artificial tears, it's like shutting the barn door after the horse is gone," says Dr. Gayton. Instead, he recommends devising a regular schedule for use of artificial tears, in order to pre-empt discomfort.

Dry eye as an allergic response to something in the environment should also be considered, Dr. Tauber says. Many patients are allergic to the acrylic in nail polish and nail glue, he notes, so that needs to be considered.

Patients may also need to change their relationships with the popular ceiling fan. "It's amazing how many patients sleep under a ceiling fan," says Dr. Tauber. "I've disrupted families by recommending they stop this for the sake of the patient's dry eye. Perimenopausal women really like the ceiling fan on; the husbands are so grateful that they don't have to sleep under it anymore. So I've gotten myself into trouble that way, but really, just stopping the ceiling fan helps."

And since extensive computer use doesn't look like it will stop anytime in the foreseeable future, educate your patients about proper positioning of the monitor to reduce evaporation, as well as the necessity of frequent breaks. "No one wants to say, ‘I'm going to take five minutes off every 20 minutes from the computer and walk away from it,’ but it does help," says Dr. Tauber.

Remind patients to remain well hydrated, which includes taking omega-3 supplements, as well as drinking eight glasses of water a day.

It is crucial to inform patients that for many of them, dry eye is a chronic condition that they will always have to tend. Many patients, Dr. Gayton says, will use up a bottle of artificial tears their doctors gave them and figure they're done with treatment.

When it comes to cyclosporine, Dr. Mah says that a little patient education can go a long way toward helping the therapy be successful. He warns patients that burning and stinging may be a factor for 10% to 20% of patients, and recommends storing the drops in the refrigerator may help to decrease these.

Be sure patients understand that optimal results from cyclosporine will take some time, Dr Mah says. "While many people do experience benefits within several weeks, the real clinical significance came about for the majority of symptoms at around four to six months," he notes. Tell patients not to give up hope if they don't experience any benefits within the first days or weeks.

These experts stress that patients need to be reminded of these points more than once. They recommend both physician and staff repeat the agreed-on patient education points, and that supplemental materials such as pamphlets and videos be used as well.

The Surgical Implications

Successfully resolving a patient's dry eye syndrome can be a powerful practice booster, often generating referrals, as has been noted. But another significant incentive is the detrimental effects dry eye has on surgical outcomes for refractive and cataract patients.

"I get referred patients all the time who, if their dry eye had been appropriately diagnosed before the surgery, their visual outcome would have been a lot better, and their level of satisfaction too," says Dr. Pflugfelder.

Dr. Gayton agrees. "Nowadays, you have to be very attuned to the ocular surface when you're dealing with cataracts," he says. "It's one of those things that affects really every advance that we've made in the field of cataract and refractive surgery. It affects preop measurements, it affects surgery technique, and it affects postop outcomes."

Patients paying for premium IOLs or LASIK surgery have high expectations, these surgeons warn. A compromised ocular surface makes it unlikely that they will achieve their full visual potential.

"Our IOLMasters, topographers, Scheimpflug cameras and wavefront instruments really are so sensitive that if the surface is anything less than pristine, it's going to get erroneous messages, and we may work on those numbers. If we act on that data, it may not be to the patient's interest," says Dr. Tauber.

The good news, he says, is that these patients are accepting of the clinician's efforts to get their ocular surface in pristine condition as part of the presurgical regime.

Between improved surgical results and increased patient satisfaction, getting your practice focused on potential dry eye is definitely worthwhile. OM

References

1. Schiffman RM, Walt JG, Jacobsen G, Doyle JJ, Lebovics G, Sumner W. Utility assessment among patients with dry eye disease. Ophthalmology. 2003; 110:1412-1419.
2. Perry HD, Solomon R, Donnenfeld ED, Perry AR, Wittpenn JR, Greenman HE, Savage HE. Evaluation of topical cyclosporine for the treatment of dry eye disease. Arch Ophthalmol. 2008 Aug;126:1046-50.
3. Rao, SN. Topical Cyclosporine 0.05% for Prevention of Dry Eye Disease: Year Two. Presented at: Joint Meeting of the American Academy of Ophthalmology and the Pan-American Association of Ophthalmology; Oct. 24-27, 2009; San Francisco.