What are the Symptoms?
The symptoms of dry eye include:
- A gritty, scratchy feeling
- Burning sensation
- Watering eyes particularly when exposed to the wind or in the car.
- Variability in the quality of vision
- Ghosting or double vision
- Tiredness sensation especially towards the end of the day
- Inability to tolerate contact lenses
What is Dry Eye & MGD?
The tear film is a complex structure of mucin, tears and oil that protects the surface of the eyes. When the tear film is compromised, it results in a variety of symptoms, most of which have been associated with Dry Eye and MGD (Meibomian Gland Dysfunction). Understanding the tear film is key to seeing the clear differences between tear deficiency issues and MGD, especially since MGD is more common and has greater long term impact on Dry Eye symptoms.
The mucin (mucous) layer at the bottom of the tear film provides a “sticky” foundation and acts as a barrier to the eye surface.
The aqueous layer is the “juicy” center that is comprised of tears produced by the lacrimal glands.
Finally, the top “oily” lipid layer of the tear film is made up of lipids or oils produced from the meibomian glands. When MGD is present, our glands do not consistently produce the oil necessary for a stable tear film and the aqueous layer will evaporate.
What are the Causes?
THE UNDERLYING CAUSE OF DRY EYE SYMPTOMS
Dry Eye is generally caused by an imbalance in the tear film that acts as a shield on the surface of our eyes. There are two primary contributors to tear film imbalance. The first is decreased tear production. In recent years, we have learned that true reduced tear production is rare. What we know now is that the problem almost always originates with blockage of the tiny Meibomian Glands in our eyelids. These glands produce essential oils that form the top layer of the tear film and are the core protective element that is essential to long-term visual comfort.
When the Meibomian glands are blocked or the glands have been compromised, the eye becomes exposed. This leads to dry eye signs and symptoms. This is known as MGD or Meibomian Gland Dysfunction. MGD is easy to diagnose and manage. The treatment of MGD is essential for the long term management of dry eye.Click here to Read More
THE LEADING CAUSE OF DRY EYE SYMPTOMS: BLOCKED GLANDS IN THE EYE LIDS
Fortunately, most Dry Eye patients boast healthy tear production as proven by a common symptom of Dry Eye, excessive tearing. As tear production is generally not the root cause of Dry Eye, your eye care professional should check for gland blockages and the structure of your Meibomian Glands in your eyelids.
Gland blockages can occur over time from debris that is caught in the eyelids, digital device and computer usage and, for women, just putting on make-up over the course of many years. While Miebomian Gland Dysfunction, or MGD, is most often detected in adults over 40, the condition does not discriminate based on age and is often seen in kids and young adults as well. That is why checking for MGD should be a part of your regular eye exam. MGD, if caught early, is the best way to avoid chronic dry eye symptoms. More importantly, you can prevent the potential for substantial permanent gland loss.
EXTERNAL DRY EYE CAUSES
Dry Eye Syndrome and chronic Dry Eye symptoms can have significant impact on daily lifestyles and can impede on simple activities such as reading, working on a computer, enjoying the outdoors or watching a TV. Those same daily activities that are impeded by Dry Eye symptoms are also the same activities that can be contributing causes to Dry Eye.
For example, looking at computers or digital devices for long periods of time can contribute to decreased blink rates. Blinking is essential to activating the oil-producing Meibomian Glands and spreading those oils across the surface of the eye. When blink rates decrease, it impacts long term functionality of the glands and can lead to MGD or even irreversible damage if MGD is not detected and treated early. Other contributing factors that cause Dry Eye symptoms to flare up are dry climates, smoke, indoor air circulation, and wind. Some of us are just lucky with Dry Eye being a product of the aging process.
MEDICAL RELATED DRY EYE CAUSES
In addition to environmental factors that contribute to Chronic Dry Eye symptoms, there are various diseases, medications or medical procedures that can cause Dry Eye symptoms. If you are experiencing any of the below medical conditions or receiving any of these treatments, you should discuss with your eye doctor to get to the root cause of your Dry Eye symptoms.
The following are common conditions or treatments that can lead to chronic Dry Eye Symptoms:
- Rheumatoid Arthritis, Sjogren’s syndrome, thyroid disease and lupus
- Medicines such as beta-blockers, antihistamines, diuretics and anxiety medications
- Refractive surgery such as LASIK surgery
- Various prescription and non-prescription medications
- Swollen, red irritated eye lids, commonly referred to as Blepharitis
- Out-turning of the eye lids (ectropion) and in-turning of the eye lids (entropion)
- Contact lens use for long periods of time
What is the Diagnosis?
MEIBOMIAN GLAND DYSFUNCTION (MGD)
The cause of Dry Eye has not been easily diagnosed in the past, due to the fact that most doctors have focused on a lack of tear production. Much research has been performed on Dry Eye causes in the past 20 years, and it is now known that, in most patients who present Dry Eye symptoms, tear production is not the primary problem. In fact, tear deficiency as a cause of Dry Eye is quite rare. For the overwhelming majority of patients with Dry Eye symptoms, blocked glands (Meibomian glands) in the eyelids are the root cause of Dry Eye Symptoms. There is an insufficient production of essential oils to protect the tear film, leaving the eye exposed and causing Dry Eye symptoms. Detecting MGD at its earliest stages is imperative to ensure long-term tear film health and avoid Dry Eye symptoms. Today, there are various tests that can be performed during your eye exam to assess Meibomian gland function and structure. Assessing Meibomian gland function and structure is essential to help determine an appropriate course of action.Click here to Read More
EVALUATING GLAND FUNCTION AND TEAR FILM HEALTH
When checking gland function, the goal is to evaluate if the Meibomian glands are secreting the right amount of oil and if the oil is of the right consistency. An assessment of gland function requires that a small amount of controlled pressure be placed over the eyelids to observe what comes out of the glands. This pressure can be applied with the help of an instrument or a doctor can lightly use their thumb or finger. The pressure is very gentle and should not cause any discomfort. The pressure is applied while you are seated at the slit lamp, so the doctor can view the gland secretions under magnification.
A PICTURE TELLS THE STORY OF MEIBOMIAN GLAND STRUCTURE
Evaluating the structure of the Meibomian glands is essential to understand how to manage your Meibomian glands over the long term. The best way to image the glands is using breakthrough imaging technology or Dynamic Meibomian Imaging® (DMI). DMI is a picture that is taken of your eyelids that shows you and your ophthalmologist:
- The appearance of the glands that you do have
- The presence of gland loss or structural changes over all
When MGD is present and not treated, the glands can begin to atrophy, much like what happens to muscles if they are not used. Gland loss can present a serious long-term problem, as there is no way to restore gland function when the glands are no longer present.