Understanding the Causes of Dry Eyes in Adults

Ben Wilkinson FRCSC, a renowned ophthalmologist, explains that the term ldquo;dry eyerdquo; now encompasses two primary conditions: ldquo;true dry eyesrdquo; and ldquo;dry eye syndrome.rdquo; Both conditions share similar symptoms that closely resemble those of ldquo;irritant conjunctivitis.rdquo; This article delves into the different causes and characteristics of these conditions.

Irrecoverable Conjunctivitis

Irritant conjunctivitis is a condition caused by the accumulation of foreign substances (junk) in the eyes that exceed the body's capacity to handle them. The causes are multifactorial and include:

Air pollution, an inevitable part of modern life. Self-inflicted irritants such as using water and shampoo during a shower without appropriate protection. Cigarette smoke, a leading irritant. Air fresheners and room deodorants. Cooking fumes. Dust from hobbies and occupational airborne irritants such as solvents and sawdust. Lid infections or other lid conditions that can contribute to the discomfort.

The symptoms of irritant conjunctivitis often include a sensation of dryness, gritty discomfort, soreness, and increased light sensitivity.

True Dry Eyes

True dry eyes result from the lachrymal glands failing to produce sufficient watery tears. This condition can be associated with the drying up of mucous membranes in other areas of the body, such as the nose, throat, and vagina. Additionally, it can lead to constipation. This general condition is known as Sjogrenrsquo;s syndrome.

The symptoms of true dry eyes include a feeling of dryness, a gritty sensation, and soreness.

Dry Eye Syndrome

Dry eye syndrome, a relatively new condition, is characterized by a reduction in the frequency of blink rate. Blinking is a natural response to vision changes, but modern activities, such as prolonged computer use, can significantly reduce the blink rate.

The symptoms of dry eye syndrome are similar to those of irritant conjunctivitis and true dry eyes: dryness, a gritty sensation, and soreness.

Diagnosis and Treatment

Diagnosing true dry eyes involves a Schirmer test to measure tear production, as the symptoms of both conditions can be highly similar. Dry eye syndrome, on the other hand, is diagnosed through a negative Schirmer test, indicating normal tear production.

Because the symptoms of dry eye syndrome and irritant conjunctivitis are so alike, they are often mistaken for each other. Itrsquo;s important to recognize that both conditions are likely present in individuals diagnosed with dry eye syndrome. Proper treatment requires an awareness of potential irritants and changes in behavior to reduce exposure. While artificial tears (drops) can alleviate some discomfort, they do not address the underlying cause.