Description

• Diseases and abnormalities of tear production and maintenance of tear film
• The most common lacrimal disorder is dry eye syndrome, which is often referred to as dysfunctional tear syndrome.
• Lacrimal duct disorders usually result in overflow tearing.
• System(s) affected: Skin/Exocrine

Epidemiology

• Predominant gender: Female > Male
• Predominant age: Dry eye symptoms increase with age and are most often seen in the elderly.

Risk Factors

• Exposure to dry environments (e.g., high altitudes)
• History of collagen vascular disease, such as rheumatoid arthritis, Sjögren syndrome, thyroid disease, rosacea, Bell palsy, eyelid abnormalities
• Medications, including oral contraceptives, diuretics, β-blockers, antihistamines, and antidepressants
• Posttraumatic stress disorder
• Smoking
• Vitamin A deficiency
• Eye surgery: Blepharoplasty, cataract, laser vision correction

General Prevention

• Prevent exposure to eye irritants from pollution, cigarette smoke, and sun exposure.
• Ensure adequate vitamin A intake through diet or as a supplement.
• Patients with prior laser vision correction should wait at least 6 months before undergoing blepharoplasty because of the effects on corneal sensation, tear production, and tear film alteration (1)[C].
• Increasing awareness of this condition among people residing in dry environments

Pathophysiology

Tear film is composed of 3 layers:

• Mucin layer: Allows spread of aqueous tears
• Thick aqueous layer: Produced by lacrimal gland
• Lipid layer: Controls tear evaporation

Etiology

• Results from poor tear production, rapid tear evaporation, and/or an abnormal concentration of mucin or lipid in tear film
• Most common cause of dry eye symptoms is aqueous tear deficiency.
• Decreased androgens are thought to contribute to a decrease in tear production.

Commonly Associated Conditions

• Sjögren syndrome
• Rheumatoid arthritis
• Thyroid disease
• Rosacea
• Pregnancy
• Menopause
• Malnutrition