Aqueous vs. Evaporative Dry Eye: What’s the Difference?
Dry eye syndrome affected people have eyes that are dry, irritating, paining and itchy. This condition is also known as Dry eye disease. It is worthy to know that there are two different types of dry eye, namely: Aqueous tear deficiency and Evaporative Dry eye disease. Treatment and management of these syndromes are based on the specific type of eye syndrome. Follow the below explanation on how to discover the type of dry eye disease you have and how to treat it.
What Is Aqueous Tear Deficiency?
The type of dry eye syndrome that occurs when the lacrimal gland in charge of tears production does not produce enough tears for effective eye functioning is called Aqueous Tear Deficiency. Research has shown that lacrimal glands maybe less effective as a result of chronic inflammation and thickened tear ducts, which can cause tears to accumulate in the lacrimal gland. This results in the age-related Aqueous tear deficiency dry eye. Other causes of ineffectual lacrimal gland include:
- Smoking: Scientists believe that smoking may contribute to Aqueous tear deficiency as a result of the oxidative stress caused by smoking, either from direct or indirect exposure. However, to determine the precise mechanism of this connection, further research must be done.
- Computer usage: A largely untested hypothesis suggests that the prolonged fixing of eyes on the computer and other screen devices such as video games, tablets and smartphones without frequent blinking of eyes can cause eye dryness.
- Existing health conditions: Aqueous tear deficiency are more widely found in patients of certain medical cases such as HIV, Hepatitis C and Sjogren’s syndrome.
What Is Evaporative Dry Eye?
Evaporative Dry eye is mostly caused by Meibomian gland dysfunction, which produce oil that helps to prevent tears evaporation from the eye surface. It is more widely found than aqueous tear deficiency. In human’s upper eyelid, there are approximately 25 to 40 of Meibomian glands while the lower eyelids house about 20 to 30. These glands may become dysfunctional as a result of clogging, leading to insufficient oil secretions that are necessary to prevent evaporation of tears, thereby resulting in eye dryness.
People are likely to be more susceptible to Meibomian gland dysfunction as a result of some risk factors such as:
- Age
- Ethnicity
- Environmental factors such as wearing makeup or contact lenses
- Bacterial or Microbial Activity
- Demodex Mites
Are There Any Similarities?
Differentiating between Aqueous tear deficiency and Evaporative dry eye disease can be sometimes difficult, as they both show similar symptoms such as dryness, redness, itchiness and general eye irritation. Between the two types, underlying inflammation is also common, but in each condition, a different part of the eye is affected, which can determine the method with which each condition will be treated.
