WHAT IS AQUEOUS DEFICIENCY DRY EYE?
Aqueous tear deficiency is caused by a decreased production of aqueous tear fluid by the lacrimal gland. Decreased tear production can be caused by Sjogrens syndrome which is an autoimmune disease effecting the tear producing glands, or by other common causes such as aging, thyroid disease or Vitamin A deficiency. Some medications such as antihistamines, anti-depressants, diuretics, oral contraceptives and following laser refractive surgery can also cause reduced tear production.
WHAT ARE SYMPTOMS OF AQUEOUS DEFICIENT DRY EYE?
Dry or gritty feeling, burning sensation, itchiness, watering, light sensitivity, red eyes, sticky tears, filmy vision, intermittent blurring vision.
TREATMENT OPTIONS FOR AQUEOUS DEFICIENCY DRY EYE?
Artificial Tear Therapy
The most common initial treatment for dry eye syndrome due to reduced tear production is lubricant drops. Many forms of lubricant drops exist, however consideration must be placed not only on the active ingredients in the formula, but also the additional preservatives that may also be present. Preservatives are designed to prevent contamination of eye drops while being stored, however their presence can have a negative impact on the ocualr surface of the eye. Preservatives can disrupt the natural tear film, and damage the cells of the ocular surface. Also commonly, people can be sensitive or have allergic responses to various forms of preservatives.
For the treatment of dry eye, it is recommended that the lubricant drops chosen are preservative free. For the treatment of more severe or chronic dry eye, the lubricant needs to have a prolonged effect to be effective. Highly viscous drops are designed to provide longer lasting relief by maintaining a longer contact time on the ocular surface. This reduces the frequency for which the drops need to be applied to remain effective. Various ointments are also available for night-time use in more severe cases of dry eye.
When lubricant eye drops alone are not enough to provide sufficient ocular comfort, a further option is to block the tear duct that is responsible for draining tear fluid from the eye. This is known as punctal occlusion and results in the retention of your own natural tear fluid, thereby decreasing the reliance on using lubricant drops. Punctal occlusion can be performed by various methods, including surgery or by the non-surgical insertion of punctal plugs in the tear duct opening. Surgical methods are generally non-reversible and must be performed by an eye surgeon. Alternatively, the insertion of punctal plugs are reversible and can be performed at this practice.
Punctal plugs are manufactured from various materials including soft silicone, PCL which is the same synthetic polymer that dissovable sutures are made from, and collagen. The silicone type may last for many years, and can be removed if necessary. PCL extended temporary punctal plugs are effective for 2-6 months, after which time they dissolve naturally. Collagen plugs are the shortest lasting, dissolving after 7-10 days. Collagen plugs are mostly used as a temporary trial to test the effectiveness of punctal occlusion for dry eye. Each of the various types of punctal plugs are gently inserted into the natural tear duct opening. Typically this practice uses extended temporary plugs (PCL) that are not permanent and have an effective treatment time varying between 2-6 months.