Types of Dry Eyes

Our eyes play a very important role in our daily life. We need good eyesight in most of our activities, so we need to get a regular eye check-up to make sure our healthy vision.

Dry eye syndrome is a multifactorial disease of tears and eye surface that results in the symptoms of discomfort, visual disturbances, and tears film instability. However, these conditions have different root causes that need to be identified for treatment to be successful. It is critically important to determine if the patient is suffering from which type of dry eye in order to provide the best and most appropriate treatment. To alleviate the problem of dry eye, we need to discuss its types. The types of dry eye are as follows:

• Aqueous Deficient Dry Eye - The lacrimal glands are responsible for producing the watery component of tears in the eyes. When tear secretion by the lacrimal glands has become insufficient or when they fail at their task, your eyes will not maintain a healthy surface which has increasingly strong relationship with the autoimmune diseases. This also causes tear hyperosmolarity, because, although the water evaporates from the ocular surface at normal rates, it is from a reduced aqueous tear pool. This condition is significantly more prevalent in women, this population as a whole represents a much smaller percentage of dry eye patients.
• Evaporative Dry Eye - Types of dry eye also includes evaporative dry eye. It is caused due to excessive water loss from the exposed ocular surface in the presence of normal lacrimal gland. Evaporative dry eye occurs when the lipid secretion of the eye, which maintains normal tear film and evaporation rates, has become abnormal. It is often caused by meibomian gland dysfunction such as by inflammation of the meibomian glands which are located in the eyelids. In this condition, your tears evaporate faster than normal. So even though your eye produces enough tears, because they evaporate your eyes become dry which causes inflammation and symptoms of irritation, redness, grittiness, and overall discomfort. This type of dysfunction is responsible for the lipid or oily part of tears that slows down the evaporation of tears, this condition makes up 86% of the dry eye population according to recent studies and is more common in women.

A mixed mechanism where the patient suffers from both evaporative and aqueous deficient dry eye may occur as well. Testing can determine which type of dry eye a patient suffers from or which carries the most weight in a particular patient.

Conclusion

Various studies suggests that there are different types of dry eyes which are based on the causes of the symptoms of the dry eye syndrome. These types of dry eyes are mentioned above, the first one is aqueous deficient dry eye and other one is evaporative dry eye. The difference between these two types of dry eye is that in aqueous dry eye, the water evaporates from the ocular surface at normal rates, it is from a reduced aqueous tear pool. But in evaporative dry eye, due to the inflammation of the meibomian glands, the tears evaporate faster than normal.