Dry eye syndrome or dry eye disease may affect as many as 40 million Americans. You have a 1 out of 10 chance of developing or having dry eyes. The numbers are increasing as more and more people are spending long periods of time staring at a flat-screen device. This could be a smartphone, iPad, computer screen, and/or TV. Something that is relatively new is that teenagers are developing dry eyes as many are spending hours playing games on a flat-screen device. This happens as they stare and diminish their blinking leading to their eyes drying out. Americans spend more than 3 billion dollars to treat dry eye disease a year. There is a 5-billion-dollar-a-year loss in work productivity in the United States secondary to dry eye disease.
What is Dry Eye Disease or Dry Eye Syndrome?
Other terms for dry eye disease are Keratoconjunctivitis sicca (KCS), dysfunctional tear syndrome, neurotropic epitheliopathy, aqueous deficiency, evaporative tear deficiency, and lacrimal keratoconjunctivitis. Dry eye disease is a reduction of the tear film that covers the surface of the eye. The tissues on the surface of the eye require a specific amount of moisture or tear film for the cells on the surface of the eye to be healthy and provide a smooth tear film surface for clear vision. If there is an insufficient level of tears present, the outer surface tissues become irritated, inflamed, and can die or atrophy. A good tear film surface is also necessary for clear vision. This is because this is the first thing that light passes through to be focused onto the retina inside the eye.
Tear Film Layer Consists of Three Layers
The inner tear film layer contains mucin. Goblet cells on the surface of the eye produce this layer. The mucin or mucous-like material coats the eye, provides a hydrophilic layer, and promotes the even distribution of the tera film.
The middle tear film layer contains water, proteins, enzymes, chemicals, electrolytes, and minerals. The lacrimal gland produces this water layer. Most people believe that this is the only component of their tears.
The outer layer contains oil or lipids produced by the Meibomian glands located in the eyelids. There are approximately 25 glands in each eyelid that produce the lipids. The Meibomian glands secrete their oil onto the tear film. The oil provides a barrier to keep the middle liquid layer from evaporating from the eye and also helps with lubrication.
Types of Dry Eye Disease
Decreased Tear Production Dry Eye Disease
Decreased liquid layer tear production composes approximately 25% of dry eye disease. The lacrimal gland is unable to produce its normal amount of liquid into the tear film.
Evaporative Dry Eye Disease
Meibomian gland disease or dysfunction accounts for 60 to 75% of dry eye disease. The Meibomian glands fail to secrete the proper amount of oil which leaves the liquid layer exposed to the environment. This exposure allows the liquid to evaporate off the eye resulting in dry eyes. There are approximately 25 glands in each of the eyelids. Secondary to chronic inflammation, the Meibomian glands begin to produce thicker and thicker abnormal oil. This thick oil plugs up the glands and eventually leads to deterioration of the Meibomian glands. The glands become smaller and eventually die. The lipid layer diminishes as this occurs.
Combination Dry Eyes
A combination of the two types of dry diseases is possible as well. No one knows for sure the number of people with a combination of dry eye disease but it could be a significant number.
Diagnosing Dry Eye Disease
This is one of the most important steps in treating dry eye disease. In order to treat dry eye disease properly, you need to know what type of dry eye disease is present and the severity of the dry eye disease. You need to have the correct amount of each of the three layers of the tear film.
The eye doctor or staff will take a history at the beginning of your visit. If you complain of any of the symptoms associated with dry eyes, many offices will have you fill out a SPEED™ or Standard Patient Evaluation of Eye Dryness or dry eye questionnaire. If you score high enough on the survey, you most likely have dry eye disease.
The eye doctor will examine your eyes with a slit lamp microscope to evaluate and examine your eyes under high magnification. There are several dyes that stain the cell walls of damaged cells on the surface of the eye. Your doctor may use these dyes to determine if the cells on the surface of your eye have been damaged and to what extent. The cells on the surface of the eye need a good tear film in order to be healthy. If there is an insufficient amount of a tear film present, the cells will die.
Our bodies are composed of water, chemicals, and minerals. The body maintains the correct level of these under normal circumstance unless there is an illness present to alter these substances.
The tear film also contains these minerals, chemicals, enzymes, and proteins. TearLab makes an instrument that can measure the salt or sodium (Na) level in the tear film. This is like a blood test that can measure the levels in the body. The levels in the tear film are not directly related to the levels in the body. The tear film is exposed to the environment and can be dramatically different from the body tissue levels. An increase in the salinity of the tear film indicates a decrease in the liquid layer of the tear film and dry eye disease. There is not enough of the liquid layer to equalize the normal body levels present in the ocular tissues. The eye doctor can use tear film osmolarity to follow or monitor the condition of the tear film and treatment success.
LipiView – Lipid Layer Measurement, Imaging, and Blinking Evaluation
The LipiView instrument measurement measures the thickness of the outer lipid layer of the tear film. It has a high-resolution movie camera and interferometer which examines the tear film and eye producing a high-resolution movie and images. The LipiView also evaluates your blinking during the test. The instrument counts each blink and evaluates each blink during the test.
During a normal blink, the upper eyelid comes down and makes contact with the lower eyelid. Due to gravity, the tears pool on the edge of the lower eyelid and the eye. The upper eyelid makes contact with the lower eyelid and the tear lake on the lower eyelid. The upper eyelid rises back up and spreads the tears back across the eye. This spreads the tears around the eye and also smoothes out the tear film like a windshield wiper to provide clear vision. If your blinks are partial or incomplete, you fail to spread the tears back across the eye. This leads to a breakdown in the tear film.
The LipiView counts how many times your blinks are partial. Its camera captures images of the Meibomian glands. Using these images, the eye doctor can evaluate the health and number of Meibomian glands present in the eyelids. The LipiView provides the eye doctor with the thickness of the lipid layer, partial blinks, and images of the health of the Meibomian glands.
InflammaDry detects the presence of matrix metallo-protease 9 or MMP-9 on the surface of the eye. MMP-9 is an excellent marker for the presence of inflammation of the eye associated with dry eye disease. An increase of MMP-9 or inflammation causes several issues on the ocular surface. This includes disruption of the corneal epithelial barrier, damage to the cell walls, increased cell turnover, and increased ocular surface irregularity.
Keratograph 5M is an ocular instrument that measures and images several characteristics of the tear film and surrounding ocular structures.
Meibomian Gland 3D Imaging
Meibomian gland imaging allows the eye doctor to evaluate the number and health of the Meibomian glands in the eyelids. These glands secrete the oily layer of the tear film.
Tear Film Break-Up Time
The Keratograph 5M measures and evaluates the stability of the tear film. The eye specialist will ask you not to blink. Then, the instrument times and measures the breakdown of the tear film without blinking to spread around new tears. People with poor tear films have their tear film breakdown faster than people with a normal tear film. Less than 12 seconds is considered abnormal.
Tear Meniscus Height
Secondary to gravity the tears pool on the junction between the lower eyelid and the eye between blinks. This test measures the amount or height of the tear film that rests on the lower eyelid. This gives the eye doctor information about the number of tears present on the surface of the eye.
Tear Film Dynamics
The instrument captures the tear film particle flow characteristics and tear film viscosity to evaluate the quality of the tear film.
Advanced Tear Diagnostics (ATD)
ATD manufactures the TearScan 270 MicroAssay System which measures Lactoferrin and IgE in the tear film. Patients with dry eye disease have lower Lactoferrin levels. If IgE levels are increased in the tear film, ocular irritation could also be related to allergies and would need to be addressed. These tests are useful in the diagnosis and monitoring of the dry eye disease and ocular allergies.
The Schirmer’s test has been around for many years. With new technologies available, eye specialists do not perform this test as often now. It is also known as:
- Dry Eye Test
- Basal Secretion Test
- Tearing Test
After the instillation of an anesthetic or numbing eye drop, the eye specialist performs this test. They place a special strip of paper on the edge of the eyelid and is left for 5 minutes. Then they remove the strip of paper and measure the length of how far along the strip the tears wet the paper. Ten millimeters or more of wetting is normal and anything less is considered abnormal.
Risk Factors for Dry Eye Disease
- Rheumatoid Arthritis and other autoimmune diseases
- Contact lens wear
- Medications – most commonly antihistamines
- Central Nervous System Diseases
- Chemical or thermal burns to the eyes
- Other Eye Diseases
As with most things as we age, the tear production slows down over time.
Dry eyes occur secondary to environmental conditions such as dry climates, outdoor with sun and wind exposure, drafts from heating or air conditioning, and decreased humidity from air conditioning. Smoking and other chemical irritants can cause dry eye disease.
The largest group of dry eye patients are post-menopausal women. There are hormone receptors on the surface of the eye which contribute to tear production. Women who are on hormone replacement therapy experience more dry eye disease. There is a 70% chance of developing dry eye disease among women who are only taking estrogen. Women who are taking estrogen and progesterone have a 30% chance of developing dry eye disease.
Rheumatoid arthritis, lupus, Sjogren’s syndrome and other immune diseases are associated with dry eye disease.
People who spend their day working at a computer or other flat screen decrease their blinking leading to dry eye disease. Jobs associated with dust, dirt, chemical fumes, cold temperatures with dry air, and others lead to the development of dry eyes.
Hobbies or Games
Anyone who stares for long periods of time doing a hobby or playing a video game is at risk of developing dry eye disease. Teenagers are now developing dry eyes as many are staring at and playing video games for hours at a time. They are not going to miss one laser shot or bomb. Parents need to limit their times to 30 minutes and then take a break.
Contact Lens Wear
People who wear contact lenses are at much higher risk of dry eyes as the loss of sensation in the cornea and low-grade inflammation contribute to the development of dry eyes.
Side effects of medications can cause dry eye disease. Some examples are anti-histamines, nasal decongestants, certain blood pressure medications, diuretics, anti-depressants, tranquilizers, birth control pills, and chemotherapy.
Central Nervous System Diseases
Patients with Parkinson’s disease and Alzheimer’s disease have very poor blinking leading to dry eyes. The average person blinks their eyes 15 times a minute. A person with CNS disease may blink their eyes 1 or 2 times a minute. This can lead to severe dry eye problems.
Neurotropic Dry Eyes
The loss or reduction in corneal sensation leads to dry eyes. Patients who have had LASIK or other similar surgeries have a decreased corneal innervation which disrupts the tear film. This is usually temporary and the corneal sensation returns in 6 months or so.
Chemical or Thermal Burns
People who suffer a burn to the surface of the eye can have enough damage to the cells producing the tear film that they have decreased production.
Women who are pregnant have their hormones altered during the pregnancy that can alter the tear film.
The eye is exposed to the environment causing dry eyes. Patients with thyroid eye disease have eyes that can protrude forward exposing the eye. Some people may not close their eyes completely while they sleep. This can happen after eyelid surgery or secondary to loose lid syndrome.
Other Eye Diseases
Other eye diseases are associated with dry eye diseases such as allergies, blepharitis, Steven’s Johnson Syndrome, and skin disease around the eye. As many as 50% of people with dry eye disease are allergic to 1 or more things in the environment.
Symptoms of Dry Eye Disease
- Itchy eyes
- Sandy or gritty sensation
- Foreign body sensation
- Painful eyes
- Blurred vision or episodes of blurred vision
- Light sensitivity or photophobia
- Stringy discharge
- Eyes stuck together in mornings
- Heavy eyelids
- Unable to wear contacts
- Unable to cry when emotionally upset
The most common complaints are that the eyes burn or itch and water. Many people think, how can my eyes water if I have dry eyes. This happens as your eyes dry out, the salt or Na levels in the liquid layer of the tear film increase. This increased salt level causes the burning, irritation, and inflammation in the eye. The only thing that your eye can do is cry or water in response to the irritation. The salt level decreases and your eye feels better. Then your eye begins to dry out again and the same process repeats itself. One of the main goals in treating dry eye disease is to maintain a normal salt level in the tear film.
Treatments for Dry Eye Disease
The first and most important step in treating dry eye disease is to determine the type and the severity of the dry eye disease. As stated before there are two major types of dry eye disease. These are decreased liquid or aqueous production and evaporative dry eye disease. Once the eye doctor has performed the tests for dry eyes, they can customize a treatment plan for your particular dry eye disease.
There are approximately 60 different artificial tears on the market. Among them are watery-like tears, gel-like tears, and ointment. Artificial tears contain a variety of different lubricants to match the deficiencies in the tear film. Artificial tears are available in large bottles containing preservatives and in small eye drop dispensers containing 10 to 12 drops preservative free. In the beginning, the mainstay of treatment is to use artificial tears on a daily basis. Your eye doctor will determine and recommend the specific type of tear drop for you after your dry eye workup.
HydroEye is an omega-6 fatty acid with GLA (Gamma-linolenic acid) from black currant seed oil and contains a small amount of fish oil. Scientific studies show that it improves the symptoms and condition of dry eye disease. It takes up to 2 to 3 months to have an effect.
LipiFlow is the only FDA approved treatment for Meibomian gland disease-causing dry eyes. The LipiFlow treatment unblocks the obstruction of the Meibomian glands. This obstruction is a result of the sick and inflamed Meibomian glands producing abnormal thick oil with a combination of localized heat and intermittent pressure.
The eye specialist places a single-use component of an eye cup and lid warmer in contact with the eyelids. The lid warmer contacts the inner eyelid surface and heats to a controlled temperature of 109 degrees. Once the lid warmer heats the oil, making it easier to remove from the glands, the flexible bladder intermittently inflates in a precise manner on the outer surface of the eyelid to express the lipid or oil out of the glands. Both eyes can be treated at the same time. The treatment lasts for 12 minutes.
The eye specialist places a single-use component of an eye cup and lid warmer in contact with the eyelids. The lid warmer contacts the inner eyelid surface and heats to a controlled temperature of 109 degrees. Heating the oil makes it easier to remove from the glands. Once the oil reaches its desired temperature, the flexible bladder intermittently inflates in a precise manner on the outer surface of the eyelid to express the lipid or oil out of the glands. Both eyes can be treated at the same time. The treatment lasts for 12 minutes.
At 4 weeks after treatment, 80% of patients reported improvement of their dry eyes in the FDA study. There is little or no discomfort with the procedure.
The MiBo Thermoflo instrument is a therapeutic medical device that provides a safe and effective treatment for dry eyes secondary to Meibomian gland disease. It uses a proprietary thermoelectric heat pump to help maximize liquefaction of the abnormal lipids in the blocked Meibomian glands. The instrument provides continuous controlled heat that is applied to the outer surface of the eyelids. Ultrasound gel is applied for a comfortable massage of the Meibomian glands. A technician uses the sterling silver plate that heats up to 108 degrees to massage the eyelids. The eyelid tissue deeply absorbs the heat resulting in loosening of the lipids and expression from the glands. The treatment is performed for 12 minutes per eye. There is a total of 3 separate treatments 2-3 weeks part.
Meibomian Gland Probing
While using a microscope, the eye doctor inserts a tiny wire probe into the narrow Meibomian gland opening on the edge of the eyelid. In some cases, chronic inflammation has scarred the Meibomian glands and/or the openings of the glands closed. This causes a reduction in the lipid layer of the tear film. Opening the scar tissue in the gland and/or its opening can allow the glands to begin to secrete their oil.
There are small openings on the medial side or toward the nose of the upper and lower eyelids called the puncta. The punctal openings lead to the lacrimal drainage duct that drains the tears from the eye into the nose. This is the reason why your nose runs when you get emotionally upset and cry. Many people believe that the tear ducts produce the tears in their eyes but instead, the ducts drain the tears away from the eye. The different glands around the eye produce the tear film. Small plugs just like miniature cork can be placed in the punctal opening. This is to block the tears from draining away from the eye resulting in more tears on the surface of the eye.
Are punctal plugs for you?
The best way to know if punctal plugs are going to be beneficial for your dry eye symptoms is to use temporary punctal plugs that dissolve in a few days. During those few days, you can evaluate the effectiveness of the punctal plugs resolving your dry eye symptoms. These types of plugs are made out of collagen.
If your symptoms are improved, a permanent punctal plug composed of silicone can be inserted to permanently block the drainage of the tears from the eyes. In the beginning, usually the bottom or lower puncta are plugged. If you are doing well and symptoms have resolved or been significantly reduced, nothing else needs to be done. If your symptoms are not reduced to a comfortable level, then temporary punctal plugs can be inserted into the upper puncta. This is done to see if they need to be plugged, as well. If you get an additional reduction in symptoms, the upper puncta can be plugged as well. There are also temporary plugs that last as long 6 months. If you are having LASIK or other eye surgery and have dry eyes, these longer lasting temporary plugs may be beneficial.
Regener-Eyes is a sterile acellular amniotic fluid eye solution containing 230+ proteins, cytokines, and growth factors. Anti-inflammatory cytokines reduce inflammation associated with dry eye disease. Growth factors help with healing, and regeneration. Hyaluronic acid helps to protect and lubricate the eye. Regener-Eyes helps reduce the pain, irritation, inflammation and stimulate the body’s natural ability to heal, repair, and regenerate.
Autologous serum eye drops use serum from your own blood to help treat dry eye disease. It has been shown to be useful in treating dry eyes as the serum contains growth factors and other nutrients found in blood. The person donates blood, the blood is allowed to coagulate, and it is placed in a centrifuge to remove the serum from the other components of blood.
Restasis is an immunomodulator that is thought to decrease ocular inflammation. Cyclosporine ophthalmic emulsion 0.05% comes in a single dose or multi-dose sterile eye drop dispenser. The medication is instilled into the eye two times a day. It may take up to 3 to 4 months to achieve the maximum benefit of the medication.
Xiidra or lifitegrast ophthalmic solution 5% binds to the integrin lymphocyte function-associated antigen-1 which is a cell surface protein and blocks the interaction ICAM-1 which is found to be elevated in the eye related to dry eye disease. This is thought to decrease inflammation in the eye secondary to dry eye disease. The medication is instilled into the eye two times a day. It may take as long as 3 to 4 months to obtain the maximum effect of the drug in the eyes.
Testosterone Cream or Solution
Research has discovered that there are hormone receptors on the surface of the eye. Post-menopausal women comprise the largest group of dry eye patients. Several studies have shown that in post-menopausal women, application of testosterone to the eyelids or solution in the eye has improved the tear film in many of these patients.
Applying warm compresses to the eyelids for a minimum of 15 minutes helps bring increased blood flow to the area. This helps keep the Meibomian glands healthier for a better oil layer of the tear film and may delay the progression of Meibomian gland disease. You can stand at the sink with a washcloth to keep it warm for the 15 minutes but that is not very convenient. Another choice is to take an old sock and fill it with rice and tie a knot in the sock. You can then microwave the sock which will stay warm for a while. Tranquileyes makes goggles that you place in the microwave to heat. These stay warm for an adequate amount of time. There are many other heating options available. Just remember to do the compresses for 15 minutes once a day.
Amniotic membranes are available to treat several different types of diseases involving the surface of the eye. The membrane is placed on the eye and the nutrients and enzymes in the membrane are absorbed into the tissues of the eye over several days. People with severe dry eye disease who have not achieved results with other treatments are good candidates for the application of an amniotic membrane.
True Tear™ Intranasal Tear Stimulator
The True Tear stimulator provides a temporary increase in tear production during neurostimulation in adult patients. It produces small electrical pulses to stimulate the production of the liquid portion of the tear film. To deliver the electrical pulses, you place in your nose a disposable tip attached to the True Tear device for a short period of time. Patients may respond differently to the treatment.
Potential Complications with Using True Tear
- Discomfort or pain in the nose
- Excessive sneezing
- Irritation or numbness of the nose
- Infection, abrasion, or inflammation of the nose
- Irritation or sensitivity of the nasal tissue stimulated
- Facial pain
- Should not use if a cardiac pacemaker implanted or wearable defibrillator. Other implanted metallic or electrical device in the head or neck
- Chronic or recurrent nosebleeds
- Bleeding disorders
- A known sensitivity to the ultrasound gel used to lubricate the device
Other Factors or Diseases Associated with Dry Eye Disease
Blepharitis is a disease of the eyelids in the area around the edge of lid where the eyelashes are located. This can be due to a variety of causes but the most common cause is the growth of Staph bacteria around the base of the eyelashes. The inflammation from blepharitis can cause meibomianitis or infection and/or inflammation of the Meibomian glands. This can also cause scarring of the Meibomian gland opening. This leads to a decrease in the lipid layer of the tear film. Treatment of blepharitis is important in treating and controlling dry eye disease.
Many people believe that they have allergies because their eyes or eyelids itch. Dry eye disease can cause the same symptoms of itchy eyes. So the symptoms do not always indicate the problem that you are having with your eyes. Many people are taking allergy medications because they believe they have allergies without knowing what they really have.
Essentially all allergy medications dry out the eyes. People are making their dry eyes worse while they think they are treating allergies. Nearly one-half of people with dry eye disease are allergic to at least one thing in their environment. It is important to get tested for any environmental allergies in the area that you live in. If you do have allergies, then you want to treat the allergy in the appropriate way that will do the least to exacerbate your dry eye disease. The results of the allergy tests will guide you to the proper treatment of your specific allergies.
Auto-immune diseases are associated with dry eye disease in many cases. The combination of dry eyes, dry mouth, and rheumatoid arthritis is called Sjogren’s syndrome. Follow your doctor’s treatment regime for your auto-immune disease as it can help your dry eye disease as well.
Which Treatment is Best?
There is no best treatment for dry eye disease. The best treatment is one that is based on the diagnostic testing done prior to beginning treatment. Your treatment should be customized to the type and severity of your dry eye disease.
If you are not producing enough of the liquid layer of your tear film, your eye doctor should base your treatment on improving that layer of the tear film. If the lipid layer of the tear film is deficient, then they should gear the treatment to the improvement of the lipid layer of your tear film. They also need to address the inflammation, if present. The eye doctor should begin with a baseline level of treatment for your particular type of dry eye disease. They then introduce additional treatments until you have reached the maximum benefit and relief of symptoms. It may take a few months to get the results that you need depending on the severity of the dry eye disease.
Dry Eye Disease Prevalence
Dry eye disease is the most common eye disease in America and is increasing in prevalence. In today’s society, adults and children are hours a day staring at a flat screen device such as a smartphone, iPad, computer, and/or TV. As they continually stare at that flat screen, their blinking diminishes, and the tear film begins to break down and evaporate from the eye. The salt or Na level increases in the tear film resulting to inflammation of the surface tissues of the eye. This inflammation may be low grade and not felt in the beginning. However, over time the severity of the inflammation will increase. The increase in salt levels also burns the nerve endings on the surface tissues of the eye. This diminishes the sensation of the eye.
The Key to Dry Eye Disease Treatment
Many people may not sense or develop severe symptoms until the disease has caused significant damage. Dry eye disease is a chronic progressive disease. If you have dry eye disease, you will need to keep working at treating it for the rest of your life. There is no magic pill that will make it go away.
The key to treatment is proper diagnosis. Again, the treatment of dry eye disease should be based on the type of dry eye disease. Just putting a few artificial tear drops in your eyes is not going to be enough in the long run. If you have children, limit their time on any of the flat screen devices. Protect your eyes from the sun and environment by always wearing sunglasses. Wrap-around sunglasses are better. If you are having any of the symptoms of dry eyes see an eye doctor. You need to get your eyes tested to know the condition of your dry eye disease. Proper treatment early on is important. It is much easier to prevent dry eye disease damage to the eyes versus trying to reverse the damage. Some of the damage can be irreversible.