dry eye
Getting Serious About DRY EYE
Our understanding of this condition keeps evolving, so stay current to provide the best treatments for your patients.
BY DEEPAK GUPTA, O.D., F.A.A.O.

There was a time when we considered patient complaints associated with dry eye a nuisance. However, we now know that this is a legitimate medical condition and is one of the more common reasons patients visit us. When you consider the fact that complaints stemming from dry eyes are also one of the more common reasons why patients drop out of contact lenses, you can see why it is so important to stay up to date on this disease. Evolving treatments help us keep our patients more comfortable and increase their chances of remaining in contact lenses.

A question of identity

If you follow the medical model in dealing with dry eye patients, then one of the first things you should do is identify pertinent risk factors for developing the condition.

► Start with the most obvious: patient complaints. Many patients with dry eyes will complain of eyes that burn, feel sandy or gritty. In addition, some will exhibit epiphora as the presenting symptom of dry eyes.

► The risk of developing dry eyes increases with age and with the female gender. Therefore, middle-aged women are particularly at risk for developing dry eye, as this population generally tends to have a higher incidence and prevalence of dry eyes. This is especially true for menopausal women, due to hormonal changes.

► Look at the work and home environments of all dry eye patients. Patients who are positioned near heating and air conditioning units in the office are more likely to demonstrate problems. The same can be said for patients who spend significant time working on computers. As we all know, prolonged computer use leads to a decreased blink rate, which in turn causes dryness in these patients.

► Also ask if a patient is taking any systemic medications, such as antihistamines, antidepressants, anti-psychotics, hormone replacement therapy (HRT) or oral contraceptives. All of these can contribute to ocular dryness.

► Ask about history of refractive surgery. Although LASIK can improve a patient's uncorrected visual acuity, it tends to sever corneal nerves and contribute to corneal surface dryness.

► Don't forget to keep contact lens wear in mind, which has been shown to decrease corneal sensation and disrupt the mucin layer of the tear film, thereby contributing to dry eyes.

Testing tears

Many tests are available for assessing tear function. The tests most commonly used in the clinical setting include the Schirmer test, phenol red thread test, fluorescein and rose bengal/lissamine green staining, tear break-up time (TBUT) and tear meniscus height measures. The major problem with most of these tests is that they lack repeatability.

In addition, studies generally show a lack of association between test signs and patient-reported symptoms. Nonetheless, they are quick and give a general sense of the severity of the patient's condition. In addition to the above, some other laboratory-based tests exist. However, they're limited clinically by either cost or by difficulty in use.

► Advanced Instruments Inc. produces several models of advanced osmometers that use freezing point depression osmometry to indirectly calculate tear film osmolarity. They're fairly accurate and are reportedly quite sensitive to dry eyes.

► The Touch Tear Lactoferrin MicroAssay by Touch Scientific, Inc. measures the concentration of lactoferrin in the tears. Lactoferrin is an iron-binding protein produced by the lacrimal gland in the aqueous tears. Measuring its concentration is an indirect way of measuring tear volume.

Getting a plan

Regardless of the diagnostic technique(s) you use, once you've made a definitive diagnosis of dry eye syndrome, you must initiate a treatment plan. This plan will vary depending on the severity, as described below. However, the key concept in this plan is requiring follow-up, which will allow you to make sure that the patient has responded to your treatment plan. Alternatively, if the patient is still not happy with his or her level of relief, it will allow you to take the next step in management. This is the case even if you prescribe over-the-counter (OTC) medications, which you will for many patients. Always underscore the fact that dry eye can develop into a serious medical condition.

Start with the basics   

Patients with mild dry eyes will do well with lubricating eye drops and artificial tears. They help to restore the compromised ocular surface to its naturally moist state. Many of these products are functionally the same and quite a few dry eye patients will instill these artificial tears several times each day. The number of OTC products available is staggering. If you have a preference, provide a sample to let patients try the medication first.

For sensitive eyes

Although the vast majority of patients do well with any of the drops, some patients run into problems with preservative sensitivity and keratotoxicity. For these patients, you can recommend the preservative-free formulation. However, many of these come in tiny plastic vials that are difficult to carry throughout the day.

Lubricant formulations that contain "disappearing" preservatives such as Refresh Tears (Allergan), GenTeal (Novartis), and Systane (Alcon) are a nice alternative. Functionally, these products serve the same purpose as the true preservative-free drops, but come in bottles for easy storage and transport.

The next level

For patients still not satisfied with the level of relief they can obtain from merely instilling drops during the day, you many want to add a gel or ointment at bedtime. These supplements last longer, but may periodically blur patients' vision, which is why q.h.s. dosing is usually the best option. Keep in mind that the use of thick gels and ointments may exacerbate an already oily tear layer and lid margin if the patient has accompanying meibomian gland dysfunction.

Punctal occlusion

If drops fail, the first and most common surgical option to consider for dry eye patients is punctal plugs. In most cases, you'll start by inserting temporary collagen plugs in the lower punctum of both eyes. Once you've inserted the plugs, schedule the patient for a follow-up visit in 10 to 14 days. Some patients won't need lubricating drops after the procedure, while others will have a decreased dependency on them.

Either way, have the patient keep track of his or her symptoms because collagen plugs dissolve in three to seven days. If the plugs improve the patient's symptoms, then insert silicone plugs for long-term management. Remember that most insurance policies have a 10-day post-op period for punctal occlusion, so you should wait at least that long before you insert the silicone plugs. If you need to remove silicone plugs, you can do it fairly easily at the slit lamp with a pair of forceps.

Prescription agents

Most patients in this moderate-to-severe category use lubricating drops and/or ointments, but are still not satisfied with their level of relief. For patients who fall into this category, you'll want to use one of two options or a combination of both.

■ Steroids. A short course of mild steroids, such as loteprednol etabonate 0.5% (Lotemax, Bausch & Lomb), help to manage the inflammatory nature of severe forms of chronic dry eyes. This site-specific steroid will help resolve the inflammation but is far less likely to cause IOP increases than other steroids. Once you've gotten the inflammatory process under control, taper steroid use and initiate a long-term management program.

■ Cyclosporine. In lieu of steroids, or in addition to steroid therapy, you can write the patient a prescription for Restasis (cyclosporine ophthalmic emulsion 0.05%, Allergan). In my clinical experience, this agent has demonstrated relevant increases in Schirmer wetting at six months, as well as a dramatic improvement in conjunctival Rose Bengal staining and corneal superficial punctate keratitis (SPK).

Studies indicate that cyclosporine has also shown improvement in patients' subjective measurements of dry eyes. The drug is indicated for patients who have dry eye caused by ocular inflammation. It reduces the cell-mediated inflammatory responses of ocular surface disease, specifically activation of T lymphocyte. Thus, the drug down-regulates the inflammatory response and allows those cells to recover their normal activity.

The biggest drawback to using cyclosporine is that it can take a patient two to six months to realize its full therapeutic effects. However, because you'll most likely prescribe it for patients in whom other therapy has failed, your patients will be more receptive to trying a medication that may take one to three months to work.

In my practice, I start patients on both loteprednol and cyclosporine simultaneously. After the cyclosporine starts to work, often one to three months later, I will taper the steroid.

If all else fails

One homeopathic treatment that's gaining recognition for managing dry eye is flaxseed oil. One tablespoon in the patient's juice of choice in the morning may provide some relief for dry eyes associated with a rapid TBUT. Other forms of the supplement are also available. One problem that might limit the widespread clinical use of flaxseed oil is the side effect of transient facial acne.

Other sources of omega-3 essential fatty acids are black currant seed oil, flaxseed, borage oil and fish oils.

Getting closer

With the diversity of options we have for our dry eye patients, there's no reason for them to suffer. As research in this area evolves, our management strategies are shifting away from lubricating drops and ointments to treatments geared toward the problem. By treating dry eye as a legitimate medication condition, we can better serve our patients and underscore our roles as primary eyecare providers.

Dr. Gupta practices full scope optometry in Stamford, Conn. He's also clinical director of The Center for Keratoconus at Stamford Ophthalmology. E-mail him at Deegup4919@hotmail.com.