By Marlane J. Brown, O.D.
What are the signs and symptoms of dry eye?
Irritation and a gritty sandy feeling in the eyes are common symptoms of dry eye. This can occur intermittently throughout the day or night, or be constant. Decreasing tolerance to contact lenses is a common symptom as well.
Symptoms do vary from one patient to the next. Most patients however, complain of a foreign body sensation, or a feeling that there is something in the eye. If you have any of the following symptoms, you may be suffering from dry eye:
- Scratchy
- Sore
- Gritty
- Burning
- Light sensitivity
- Decreased vision
- Tired eyes
- Decreased tolerance to contact lenses
How prevalent is dry eye?
Some sources report that dry eye is prevalent in 5-14% of the population. It is more common in women nearing or past menopause, affecting 3.2 million American women middle aged or older. It is also commonly seen in contact lens wearers, computer users, and patients who have had eye surgery.
Dry Eye: Oasis
What causes dry eye?
No one thing causes dry eye. Albietz presented an article (“Prevalence of dry eye subtypes in clinical optometry practice.” Optom Vis Sci. July 2000) which classified dry eye into several categories. These were:
- Lipid anomaly
- Tear deficiency
- Mucin anomaly
- Allergic/Toxic
- Blinking problems
- Primary epitheliopathies
Other causes may include deficiencies in the sensory nervous system, motor nervous system, or target organs such as the lacrimal gland.
Environmental factors such as wind, pollution, sun, and dry air inside homes or offices definitely affect the eyes, but especially in a patient with dry eyes. Patients usually do not produce enough natural tears to offset these and other environmental irritants.
Systemic autoimmune disease sufferers, such as those with sjogren’s disease, most often have problems with dry eyes. Patients with tear deficiency due to sjogren’s or for any other reason, have compromised corneas and conjunctivae. When there is a tear deficiency, “T” cells are activated, cytokines are released on the ocular surfaces, and this disrupts the corneal lacrimal reflex. Resulting chronic irritation causes progression of the disease.
Clinically dry eye presents in varying degrees. Mild disease is associated with superficial punctuate epithelial erosions on the cornea and conjunctiva. Severe disease may show filamentary keratopathy and severe puntate epithelial erosions. Untreated, dry eye may lead to sterile ulcerative ‘melting’ or even bacterial keratitis.
Dry Eye: Oasis Animation
Testing for Dry Eye
Your eye doctor will ask you questions to find out about your lifestyle, work and home environments, work requirements, and even nutrition habits. Often he or she will measure your tear volume or tear production using one of several tests. These tests may include “Schimers Tear Test”, “Lissamine Green” staining, “Rose Bengal” staining, and “Flourescein Dye” staining. These determine the degree of dryness and the location of the dryness on the eyes.
Treatment for Dry Eye
Traditional treatment for dry eye may include lubricating eye drops, thicker eye ointments, punctal plugs, or even suggesting lifestyle changes. Traditional treatments often treat the symptoms and some patients do get relief from these simple treatments. However, traditional treatment do not address abnormal tear quality or composition, health of the ocular surface and lacrimal gland, or underlying disease process.
New treatments include some of the newer artificial tears, topical cyclosporine eye drops, steroid eye drops, oral antibiotics, and oral nutritional supplements.
Studies continue to be done on new ways to treat dry eyes. Emerging treatments include “secretagogues” which will stimulate secretion, “mucomimetics” which will mimic the mucin level, and “anti-evaporatives” which will stimulate lipid secretion and optimize barrier function. Other emerging treatments are working with hormone replacement and nutritional supplements.
If you have or think you have dry eye, and are suffering with it’s symptoms, be certain to contact your eye doctor to discuss new and emerging treatments for this frustrating syndrome.
