What exactly causes Dry Eye Disease? Why did my doctor diagnose me with Dry Eye Disease when I’m experiencing excessive tearing? Why does my vision fluctuate? Why do my eyes feel heavy and tired at the end of the day?
Dry Eye is a chronic inflammatory condition resulting in an inadequate tear film. Dry eye affects 10-20% of the population in the United States and approximately 5 million people over the age of 50, though this number is expected to increase significantly over time. With an increase in the prevalence of Dry Eye, the definition of Dry Eye has evolved over time. Initially defined as “a disorder of the tear film due to tear deficiency or excessive evaporation”, the 2017 Dry Eye Workshop (DEWS) II Report modified the definition to describe dry eye as an inflammatory condition associated with disrupted tear film homeostasis, or biological balance. The most recent DEWS Report, DEWS III, was released in 2025, updating the definition of Dry Eye to emphasize the instability of the tear film as the major route cause of signs and symptoms.
Dry Eye Disease is characterized by a long list of signs and symptoms. Signs are what the doctor sees; symptoms are what the patient feels.Symptoms of dry eye include burning, itching, irritation, foreign body sensation, grittiness/scratchiness, tearing, fluctuation in vision, and eye fatigue. Signs of dry eye disease include inflammatory markers in the tear film, elevated tear osmolarity (or salt content), blocked or impacted oil glands within the eyelids, loss of oil glands within the eyelids, redness along the eyelid margin, increased redness over the sclera (the white part of the eye), and corneal surface staining with fluorescein dye.
How is Dry Eye Disease diagnosed? During your comprehensive eye exam, your doctor will perform an ocular surface examination using a slit lamp biomicroscope. Such examination involves looking carefully at the eyelids, conjunctiva, and cornea. Frequently, fluorescein dye is used on routine examination to assess for corneal damage associated with dryness. Fluorescein dye highlights areas of cell disruption; when yellow staining is present, this indicates anatomical changes associated with dryness that may potentially impact vision and increase risk for complications such as infection. Fluorescein dye also allows for the measurement of your tear break-up time (TBUT). Your Tear Break-Up Time determines how fast your tears evaporate off the surface of your eye. The faster the rate of the evaporation, the more likely you are to experience fluctuation in vision.
Advanced diagnostic tests may be warranted if there are significant signs and symptoms of Dry Eye Disease. Tear Osmolarity testing measures the salt concentration of your tears to understand the stability and balance of the tear film. With a higher salt concentration, there is more imbalance in the tear film, which leads to worsening Dry Eye symptoms. The RPS InflammaDry® test measures the level of MMP-9 (an inflammatory protein) in your tears to determine the presence of inflammation present. Inflammation in the tear film often results in symptoms of irritation, burning, and itching. Higher degrees of inflammation increase the risk of corneal cellular damage associated with Dry Eye. Both Tear Osmolarity and Inflammadry testing are important biomarkers that allow us to monitor the effectiveness of dry eye treatment. Meibography is performed using a specialized camera to image the Meibomian glands within eyelids. The Meibomian glands are responsible for producing the oil layer of your tear film. These glands may become blocked or atrophy, resulting in poor oil quality within the tears. By using Meibography, we are able to understand the gland anatomy to determine which dry eye treatments may be right for you.
Dry Eye Disease has a variety of treatments, from over-the-counter remedies to prescription drops to in-office procedures. Each Dry Eye patient is unique, and therefore each treatment must be tailored to the specific patient. Check out the Dry Eye Treatments page for more detailed information on the variety of treatments your doctor may prescribe for Dry Eye Disease.