Dry Eye Diease

Dry eye disease affects millions of patients and occurs when your eye doesn’t produce enough tears or produce poor quality tears. Dry eyes feel itchy, they may sting, cause burning or foreign body sensations, and make you more sensitive to light. To understand dry eye disease, you need to first understand how tears work. There’s a film of tears that’s spread over your eye at any given period: this is known as a tear film. Tear film is important for keeping your eye’s surface clear, providing lubrication, and to decreasing the risk of infection. Tear films are made of 3 distinct layers. The oily layer, produced by meibomian glands, is the outermost layer and helps to keep the tear film smooth and prevents it from evaporating too quickly. The watery layer is the middle layer of the tear film and its purpose is to keep your eyes clean by rinsing away particles. This layer is made by lacrimal glands in your eyelid. The mucous layer is the innermost layer of the tear film and it helps to spread your tears over the surface of your eye. This layer is produced in the conjunctiva. All 3 layers are necessary in order for your tears to lubricate your eyes. If the production of the tears or if the composition of any part of your tear film is disrupted, then you may experience dry eye disease.

Inadequate amount of tears

Not producing enough tears (aka aqueous tear-deficient dry eyes) is most common type of dry eye disease among postmenopausal women. This type of dry eye disease may also be an indication of other medication conditions such as Sjogren syndrome, rheumatoid arthritis, or lupus. Environmental factors such as wind/dry climate may also decrease your tear volume or increase evaporation of existing tears. 

Poor quality of tears

Abnormal tear composition can cause your tears to evaporate quicker and this is known as evaporative dry eyes. This can also be caused by keeping your eyes partially open for long periods of time (ex. Nocturnal lagopthalmos) or by infrequent blinking (which can be caused by Parkinson disease). The most common form of dry eye disease occurs when the watery, middle, layer of your tear film is deficient. This condition is formally known as keratoconjunctivitis sicca.

Dry eye disease diagnosis

Speak to your optometrist about your symptom history. Your specialist can look at your eyes under a slit lamp to see if you have surface damage on your eyes indicative of dry eye disease. To help with this process, your doctor can use a fluorescein eye to temporarily stain the damaged areas on your cornea to make them more visible. Doctors can also measure a tear break up time to see how long it takes your eyes to become dry when staring or administer a Schirmer test to see how much tears your eyes are producing. 

Dry eye disease treatment

In addition to the following recommendations, there are some lifestyle changes that you can make to help alleviate your dry eye disease. Try to stay away from very warm rooms in the winter or use a humidifier if the heater is on high. Avoid hair dryers and protect your eyes from wind by using wrap-around glasses. Increasing your intake of omega-3 fatty acids can help with your symptoms and remember to blink regularly when reading or looking at a computer screen.

Adding to your tears

Patients with mild symptoms may benefit from using artificial tear drops. These drops are designed to mimic real tears and they help to coat your eye and retain moisture. Over-the-counter lubricating ointments are also available and can be used before sleeping to help prevent dryness in the morning. Many over non-prescription formulations can be used as frequently as needed, every few hours. Speak with your pharmacist to find out the differences between the numerous choices available. If you find yourself using artificial tears more than 6 times daily, or if you’re allergic to preservatives, choose a preservative free formulation to avoid irritation. Warm compress and eyelid massages are commonly recommended as well. 

Conserving tears

Your doctor may recommend blocking your tear ducts to help you keep tears in your eyes longer to decrease your symptoms. Small tear duct plugs known as punctal plugs are available to temporarily achieve this or, rarely, surgery is available to permanently close your tear ducts. 

Increasing your tears

2 commonly used prescription eye drops used to help with dry eyes are Restasis and Xiidra. Restasis (cyclosporine) is the older medication that helps to decrease inflammation in your eyes to promote tear production. Xiidra (lifitegrast) has been available since 2016 and also decreases inflammation in your eyes (although the exact mechanism is unclear). Both of these medication take weeks to work. Benefits from Xiidra are usually reported in 6-12 weeks whereas it may take up to 16 weeks to feel any benefits from Restasis. Both of these eye drops cause a stinging and burning sensation when applied but these side effects are more common Restasis. Restasis is not for contact lens wearers but you can insert your contact lens 15 minutes after using Xiidra.