Dry eye is an uncomfortable and potentially harmful condition in which the eye fails to produce enough tears. This vital substance does much more than just lubricate the eyes. Tears also safely wash away foreign bodies and contain an antibacterial substance called lysozyme that fights invasion by pathogens. Tears also deliver healing compounds that repair damage and promote eye health. The front clear window part of the eyeball is called your cornea. The fastest healing area in the entire body, the cornea gets its oxygen supply directly from the air. This is one major reason why contact lenses can cause dry eye, especially if worn for prolonged periods. The lenses can block oxygen from reaching your corneas. A lack of corneal blood vessels is the primary reason why corneal transplants are rarely rejected. With no involved blood vessels, the body doesn’t seem to recognize the transplanted tissue as foreign, and so it doesn’t attack it.
What are the Symptoms of Dry Eye?
Itching and redness.
A feeling of sand in the eye.
Blurry vision and a sensitivity to light.
Feeling like something is in the eye when there isn’t.
Diagnosis of Dry Eye
Doctors use a variety of methods to diagnose this problem. First, there will be a thorough eye exam and an evaluation of your personal and family medical history and overall health, including any chronic medical problems you may have. Then, a number of tests may be conducted.
One test is the Schirmer test, where a special kind of blotting paper is placed under the lower eyelids for five minutes. After that, the doctor can measure your tear output by looking at the paper.
The phenol red thread test is also used to measure tear production. This uses a piece of dyed pH-sensitive thread. The thread is placed into the lower eyelid for 15 seconds. The thread changes color when exposed to tears, allowing the doctor to measure the amount of tears.
Special eye drops containing medical dye can also be used to evaluate tear quality. As the drops coat the eyeball, the doctor watches for staining patterns and also the tears’ evaporation time.
The doctor may perform special tear tests that look for known markers of dry eye. The tears can also be analyzed for moisture and particle content, with the level of moisture indicating a possible dry eye issue.
What Causes Dry Eye Syndrome?
Dry eye syndrome is more than just an occasional episode of dry eye. This syndrome is persistent and may result in abrasions to the cornea and even partial vision loss. Some causes include:
This is a disorder of the eye’s Meibomian gland and is known as MGD. In this disorder, the gland fails to produce enough oil in the tears, causing them to thin out and dry up too quickly. The most common cause of dry eye, it can also cause a crusting and inflammation of the eyelids and rims called blepharitis.
More common in people with rheumatoid arthritis and lupus, both autoimmune diseases in which the body’s malfunctioning immune system attacks its own tissues, this syndrome is often also accompanied by a dry mouth. As part of widespread systemic inflammation, the autoimmune disease targets the eye’s surface tissue, causing dryness.
The risk of dry eye increases with age. Other causes include unsuccessful cosmetic surgery around the eye area that may have left the eye unable to close properly and lifestyle issues like smoking and severe sleep loss.
Eye strain, especially from looking for long periods into a computer screen and side effects from antihistamines are other possible causes. Diabetes and sleep apnea can sometimes contribute to symptoms of dry eye, too.
Although today’s brands of contact lenses are more breathable than ever before, they can still cause dryness in some individuals, especially if they’re not properly cared for.
How to Relieve Dry Eye
Treatment depends on the cause. Sometimes, there may be an isolated incident of the condition, easily managed with over-the-counter eye drops specifically designed to lubricate the eye.
It’s important to choose a brand intended for this and not some other brand formulated to clean contact lenses or remove redness.
Ophthalmic cyclosporine eye drops and ointment, available by prescription only, may relieve dry eye with an autoimmune cause. Previously resistant to treatment, these conditions respond well in many cases to these medications.
Cyclosporine is an immunosuppresant typically used to prevent rejection of transplanted organs. Side effects can be severe, but when the drug is used locally in the eye, there is no systemic effect. Cyclosporine works by calming the immune system response and reducing swelling, allowing the tear glands to work normally again.
Blepharitis can be managed with warm compresses, antibiotics and anti-inflammatory medications.
Sometimes, tear duct plugs may help with dry eye. These plugs are inserted into the ducts by a physician in a simple office procedure. They work by preventing tears from draining back out of the eye.
Lubricating eye inserts that look like a tiny grain of rice are also available by prescription. These are inserted into the eye once a day and release a steady stream of continuous moisture into the eye.
How Long Does Dry Eye Last?
Yes, in some cases, the condition is temporary. It depends on the cause. If it’s autoimmune, it’s unlikely to clear on its own, and medical attention will be required. Lifestyle causes can be reduced or eliminated.
It’s possible for the condition to be related to nutrition as well. A poor diet high in sugar and processed foods and low in healthy fats could aggravate dry eye. Improving your diet and adding an Omega 3 fish supplement may help.
What is the Best Eye Drops For Dry Eyes?
The best eye drops available without a prescription are designed just for dry eye. Look for terms like lubricating drops, artificial tears and moisturizing drops. The label should state specifically that the product is for dry eyes and nothing else.
Some of these products are in gel or ointment form. Because they’re more concentrated and thicker than drops, they may work better. These ointments are only suitable for bedtime use because they tend to cause temporary blurry vision.
Look for ingredients like carboxymethylcellulose, glycerin, propylene glycol, polyethylene glycol, polyvinylpyrrolidone or povidone, hypromellose, sodium hyaluronate, polyvinyl alcohol, mineral oil and polysorbate. Some top brands include:
Refresh OPTIVE lubricant eye drops. This is available in single-use dose units that are preservative-free.
Refresh Celluvisc lubricant eye gel. This also comes in single-use containers.
Systane Ultra lubricant eye drops/eye gel. This formula is thick, comforting and long-lasting. It provides instant, soothing, reliable relief.
If you’re having problems with dry eyes, don’t wait to seek medical help. Schedule a dry eye exam with one of our premier doctors for a thorough eye health evaluation. Our professional staff will be happy to assist you.