Dry Eye & Inflammation

One of every four eye exams involves a case of dry eye disease, where along with symptoms of red eyes, irritation, dryness, and itchiness is inflammation. Although symptoms differ on how they affect the eyes, inflammation can certainly damage the ocular surface in dry eye disease. For optometrists who examine dry eye patients, inflammation plays a key role in diagnosis & treatment, especially when determining the form of dry eye. Dry eye disease develops either from an imbalance in tear composition or a deficiency in tear production. Our tears are composed of water, oil, and various amounts of chemicals*, and when the body produces too much water, this leads to an evaporative dry eye. Since the tears evaporate too quickly, the leftover chemicals & oils build-up to create a concentrated tear film layer. This can lead to blocked meibomian glands or meibomian gland dysfunction.* So, while you may be able to create tears normally, you’d still suffer from irritation & dryness. Evaporative dry eye is the leading cause of dry eyes with over 80% of dry eye patients. The less common form of dry eyes is when one can’t generate enough tears naturally, which is called an aqueous tear-deficient dry eye. In mild cases of dry eye disease, eye drops or artificial tears, and even warm compresses can soothe the irritation and possibly deal with the symptoms. However, for those with moderate to severe dry eye, stronger treatments are necessary. In an evaporative dry eye, for example, the concentrated, hyperosmolar solution damages the cells on the ocular surface eliciting the inflammatory response. Inflammation also can lead to MGD since the glands no longer can secrete tears properly. Treating inflammation early on can reduce the development of MGD and keep your tear flow as normal. Some treatments like Restasis or Xiidra reduce the amount of inflammatory response by restoring the balance of your tear’s composition and increase their rate of development, however, when one has MGD or blocked glands from a concentrated tear film, this doesn’t deal with the problem directly. Some technologies use heat or light to clean the glands directly and manually express the trapped liquid inside the glands. As far as to tear deficiency, however, medicated eye drops that aim to increase natural tear flow would help treat that case of dry eyes. Therefore, inflammation often appears when the skin or ocular surface is being damaged directly, where a dry eye expert can start determining which treatment to utilize.