Glaucoma can cause vision loss, when a patient has both dry eye syndrome and glaucoma, the glaucoma is usually treated first. Addressing the glaucoma almost always takes precedence over treating the dry eye disease – even though the dry eye bothers the patient more.
As people age, an increased interest and heightened awareness of the changes occurring on the ocular surface is necessary. It’s not uncommon in this older patient population to see age-related changes on the ocular surface that affect the protective and nutrient functions of the tear film.
These changes can include laxity of the lids, dropout of the meibomian glands, decrease in goblet cells and an increase in dry eye related to a decrease in acinar cells of both the main and accessory lacrimal glands.
In fact, aging itself is a drying process. A decrease in body water in the elderly makes them susceptible to dehydration, and can play a factor in initiating or exacerbating ocular surface disease symptoms such as dryness, burning, stinging, grittiness and foreign body sensation.
Because both glaucoma and ocular surface disease are highly correlated with the age of the patient, ophthalmologists frequently see patients treated for glaucoma who are also exhibiting signs and symptoms of ocular surface disease to a greater or lesser degree.
Physicians treating patients who have both these conditions tend to focus on the glaucoma because of its Vision threatening potential, while patients are focused on the ocular discomfort associated with dry eye.
It is important for us to also pay attention to dry eye in these patients because it negatively impacts adherence to glaucoma treatment, quality of life, and surgical outcomes. The goal is to treat both concurrently so patients are comfortable and have a well-controlled IOP.
The first step is to specifically look for the presence of dry eye disease. A basic approach that includes listening to the patient’s symptoms and looking for the signs associated with dry eye disease during the slit lamp examination.
Other helpful tools for the evaluation of dry eye disease include symp – tom questionnaires, measurement of tear osmolarity and inflammatory markers in the tear film, and meibomian gland imaging.
Patient education should be included in the management strategy with a specific discussion of both glaucoma and dry eye and how treatment of one affects the other. The patient should be fully committed to the treatment plan, because glaucoma severity is generally the primary factor that guides management and patient adherence is critical to preserve vision.
Dry eye has a number of contributing factors and use of glaucoma medications is just one. Eliminating glaucoma medications does not result in complete resolution of dry eye in most patients.
Patients with glaucoma and dry eye have several options, including selective laser trabeculoplasty (SLT), medications, and surgery. SLT can be used as either first-line or adjunct therapy. Primary SLT, which is helpful in patients with glaucoma and dry eye, provides good efficacy and lacks the side effects of topical medications.
However, the effect decreases with time, and not all glaucoma types can be treated. There are rare complications, such as keratitis, that can affect vision. For medical therapy, we recommend using drugs without BAK or those with a non-BAK preservative.
It is also helpful to reduce the drug frequency, if feasible. Switching from a preserved to a preservative-free prostaglandin has been shown to result in markedly improved signs and symptoms of ocular surface disease.
Barriers to use of preservative-free or non-BAK preserved medications are cost, lack of accessibility through insurance, and patient difficulties using preservative-free vials. Fixed-dose combinations can help reduce BAK exposure.
A sustained-release bimatoprost intracameral implant (Durysta, Allergan) was approved for single-use in 2020. Its acceptance by patients and doctors for treatment of a chronic disease remains to be determined.
For advanced ocular surface disease, autologous serum and scleral lenses may be considered. Consultation with a cornea specialist is helpful in patients with dry eye and glaucoma.
If steroid treatment is being considered for the ocular surface, it is important to discuss the risk of IOP elevation and closely monitor the patient.
Glaucoma and dry eye often coexist. Treating both is equally important, because dry eye left untreated can adversely impact glaucoma management. Treatment should be individualized based on the severity of the two diseases.