About Dry Eyes
Symptoms of Dry Eyes
Lacritec is designed for patients who are experiencing Dry Eyes. Common symptoms of dry eyes include:
- Blurred Vision
- Gritty feeling
- Light Sensitivity
Causes of Dry Eyes
Many different things cause dry eye syndrome. The normal ageing of tear glands, as well as extended use of contact lenses, environmental pollutants, prescription drugs, refractive surgery, auto immune diseases, nutrient deficiencies and other disorders can cause disruption in the tear production and retention process.
Dry eye syndrome affects 75% of people over age 65. Tear volume decreases from age 18 as much as 60% by age 65. Hormonal changes cause decreased tear production brought on by pregnancy, lactation, menstruation, and menopause.
Extended Contact Lens Wear
Extended contact lens wear can result in dry eye from corneal oxygen and nutrient deficiency. Protein build-up on the contact lens can produce a breeding ground for bacterial growth and surface roughness, further contributing to inflammatory changes. Some contact lens solutions contain preservatives that can also cause chemical irritation of the corneal surface and result in dry eye symptoms.
Blepharitis can often cause dry eye symptoms due to inflammation of the eyelid margins, which is caused by a bacterial infection (Staphylococci). This condition can compromise the quality of the tear film causing tears to evaporate more quickly. The bacteria produce waste material that can cause a mild toxic reaction leading to chronic red, irritated eyes.
LASIK Surgery temporarily disrupts the ocular surface / lacrimal gland unit. Also, during LASIK, roughly 60-70% of the superficial nerve fibres in the cornea are severed, which reduces sensation and affects aqueous tear production and delays wound healing. With compromised sensation, the blink rate can slow to the point that the tear film breaks up before the next blink can reconstitute. Though this condition usually clears up after a few months, it may result in mild to severe dry eye syndrome for several months after surgery.
Computer use causes most people to blink less frequently (about 7 times per minute vs. a normal rate of around 22 times/minute). This leads to increased evaporation along with the fatigue and eye-strain associated with staring at a computer monitor. Any task requiring a great deal of concentration can result in decreased blink rate.
Medications that can cause dry eyes include antibiotics, blood pressure medications, antidepressants, diuretics, some eye drops, cold and flu medications, antihistamines, birth control pills, appetite suppressants, and ulcer medications.
Diseases that may be associated with dry eyes include Rheumatoid Arthritis, Sjogren's Syndrome, Diabetes, Asthma, Thyroid disease, Lupus, and Glaucoma.