Dry Eye and Ocular Surface Treatment Center.
Dry Eye and Ocular Surface Disease
Dry Eye and Ocular Surface Disease is a general classification of disorders affecting the front surface of the eyes. The most common form is Dry Eye Syndrome. These diseases include but are not limited to keratoconjunctivitis sicca, dry eye syndrome, meibomian gland dysfunction, blepharitis, rosacea, allergies, chemical burns, thermal burns, and immunological conditions such as Sjogren’s syndrome, rheumatoid arthritis, systemic lupus erythematosus, and graft versus host diseases.
Patients with Dry Eye and Ocular Surface Disease may complain of eye stinging, burning, foreign body sensation, sandy or gritty sensation, tearing, itching, redness, irritation, pain, light sensitivity, and difficulty wearing contact lenses. These symptoms often worsen at the end of the day or after focusing for a prolonged period on a near task. It is common for vision to fluctuate or to be blurred as a result of Dry Eye and Ocular Surface Disease.
Dry Eye and Ocular Surface Diseases can severely affect eyesight and quality of life. In severe cases loss of vision due to corneal scarring can occur.
At the Dry Eye and Ocular Surface Disease Clinic, Dr. Pamel and his associates use of the most comprehensive and advanced diagnostic tools to target the cause of Dry Eye, only then can the treatments and management be tailored to each individual’s needs. With this advanced personalized treatment we can reduce or eliminate discomfort and improve the quality of life.
Understanding the Tear Layer and its role in Dry Eye and Ocular Surface Disease
The tear layer is eye’s first defense. It is composed of three layers: a lipid layer, an aqueous layer and a mucous layer. Each layer must be present and healthy to provide lubrication, comfort, protection, and visual clarity. A deficiency in any layer can create a problem leading to the symptoms above.
- Lipid Layer: The purpose of the lipid layer is to maintain tear quantity and fight evaporation. This lipid layer is produced by the meibomian glands that are the tubular glands that line the inner lid margin. These lipid secretions should be thin and easy flowing, but many individuals suffering from dry eye and ocular surface disease have glands that are clogged, or in some severe cases have atrophied or scarred over leading to evaporative dry eye.
- Aqueous Layer: The aqueous layer or the “watery layer” of the tears contains water, enzymes, and proteins to help protect the eye. This layer is secreted by small glands in the conjunctiva as well as the lacrimal gland. The aqueous layer makes up the bulk of the volume of tears and is responsible for tear spreading. Tear production tends to diminish with age, various medical conditions, or as a side effect of certain medications. Some systemic diseases such as Sjögren’s Syndrome can cause a severe reduction in the volume of aqueous layer produced.
- Mucin Layer: The mucin layer works to hold the tear film to the eye. It coats the eye and allows for even distribution of tears across the ocular surface. This layer is produced by goblet cells found in the ocular surface. Deficiencies in the mucin layer are most caused by diseases that involve mucus membranes such as Stevens-Johnson Syndrome and ocular cicatricial pemphigoid.
Causes of Dry Eye Syndrome:
The definition of dry eyes has evolved over the last twenty years. In 2007, the Definition and Classification Subcommittee of the International Dry Eye Workshop (DEWS) classified dry eye as a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance and tear film instability, with potential damage to the ocular surface.
The DEWS definition also states that dry eye is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface. These features lead to the dry eye cascade of visual degradation, epithelial cell damage and discomfort. Osmolarity is the relationship between the water in the tear film and the solutes (chemical substances) that make up the tear film. In the dry eye condition, the loss of water from the tear film alters the ratio and results in an increase in osmolarity.
Females are affected more than males and most individuals with this condition are female, over the age of 30. According to the Women’s Health Study, the prevalence of dry eye affects more women as they age.5 Although the prevalence increases in men as they age, it is not as common as in women. Also, women who used hormone replacement therapy (HRT) had a 69% greater risk of developing dry eye syndrome. If estrogen therapy was combined with progesterone/progestin, the risk went up another 29%. The risk of dry eye increased 15% for every three-year interval that the women remained on HRT. Many patients develop a dry eye condition over years and decades before it is recognized.
Many factors can cause dry eye or exacerbate an existing dry eye condition. These include:
- Extended visual tasks, such as prolonged computer use.
- Systemic medications that have drying side effects, including antihistamines, hormone replacement therapy, diuretics, antidepressants and antianxiety medications, cancer treatments and some sleep aids.
- Excessive consumption of alcoholic beverages.
- Long-term exposure to dry air, as found in the desert Southwest, for example, or windy climates. Also, dryness increases in the winter months as the humidity decreases with falling temperatures.
- Use of forced-air heat or air conditioning.