Dry Eye Syndrome

Dry eye syndrome, also known as keratoconjunctivitis sicca, is an ocular condition characterized by insufficiency of the components of the tear film. The tear film provides lubrication to the eye, allowing clear vision while protecting the eye. Moisture, oxygen, and nutrients are provided by the middle aqueous layer which is sandwiched between the inner mucin layer and outer lipid layer. The basal mucin layer anchors the tear film to the conjunctival and corneal epithelial cells and regulates the surface tension. The outer lipid layer reduces the evaporation of tears from the ocular surface.

Dry eye syndrome is common, affecting 5 to 30% of the US population, and those of the female gender are at a higher risk of developing it. The increasing incidence of dry eye syndrome worldwide is attributed to the increased screen use, smoking, an increase in the human lifespan coupled with increasing healthcare costs, and development of chronic diseases and the medications used to treat them.

What causes Dry Eye Syndrome?

The etiology of dry eye syndrome is multifactorial, causing a disruption in the homeostasis tear film, increasing the osmolarity, or inciting inflammation. Two main pathomechanisms contribute to the development of the disease.

  • Decreased production of tears can occur due to diseases like Sjogren’s Syndrome, blockage of the lacrimal ducts, or due to side effects from medications.
  • Increased evaporation of tears that may be the result of Meibomian gland dysfunction, poor blinking, environmental factors like low humidity, and problems with palpebral aperture.    

Other inflammatory conditions that can contribute to the development of dry eye syndrome include xeropthalmia caused by Vitamin A deficiency, allergic conjunctivitis, and toxicity from preservatives in topical medications.

Common symptoms of Dry Eye Syndrome

  • Stinging and burning
  • Pain in the eye or surrounding tissue
  • Gritty or foreign body sensation
  • Itching
  • Irritation and redness
  • Increased production of tears or discharge
  • Blurry vision
  • Sensitivity to light

Symptoms may be worse at the end of the day or with prolonged use of the eyes. 

Treatment of Dry Eye Syndrome

Early treatment and prevention are important prognostic factors in dry eye syndrome. Possible systemic causes and side effects from medications should be assessed and treated accordingly. 

Mild symptoms of dry eye syndrome may be treated with conservative management:

  • Frequent breaks while driving or use of screens (watching television, or using the computer and smart devices) as the average blinking rate has been shown to be significantly decreased during these activities.
  • Reduce dryness in the environment with the use of a humidifier or decreasing heating or any form of direct high airflow.
  • Warm eye compresses.
  • Smoking cessation.
  • Decreasing use of contact lenses
  • Topical ocular lubricants.
  • Supplementation with essential fatty acids.

More severe or refractory symptoms may need more rigorous treatment in addition to conservative management. Treatment options may include:

  • Topical anti-inflammatory medications, such as corticosteroids, cyclosporine, and lifitegrast.
  • Oral tetracycline antibiotics.
  • Night-time ointments.
  • Moisture goggles.
  • Intense pulsed light therapy
  • Serum eye drops.
  • Oral or topical secretagogues.
  • Scleral contact lenses.
  • Surgical management, such as reversible or permanent punctal occlusion, amniotic membrane grafting, tarsorrhaphy, and salivary gland autotransplantation.

Source: Golden MI, Meyer JJ, Patel BC. Dry Eye Syndrome. [Updated 2021 Nov 2]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470411/