Usually our eye is lubricated and moisturized by the tear film . Tear film makes our eye comfortable and moisturizes but sometimes tear can be inefficient or quality of tear might be very weak which leads Dry Eye. Tear is produced in two ways.one of which is continuous tear production and second one is overproduction of tear due to weeping, cold air or wind, foreign object damage and catching cold or flu may cause overlacrimation. It is interesting that dryness on the eye and contact lens usage can cause lacrimation too.
Symptoms of Dry Eye
- Burning or itchy feeling
- Have mucous ropes inside of the eye or around it.
- Heavy lacrimation and tiredness
- Uncomfortable feeling on contact lens usage
What ıs tear fılm layer?
When we blink, tear covers eyeball and it makes layer on it. It is called Tear Film Layer. There are oil, mucous, electrolyte, vitamins, sugar and amino acid in Tear Film Layer. It nourishes front layer of the eye. It provides oxygen trespassing and protect from materials. It is impossible to have a clear vision without this layer. It contains immunoglobulin and immunomodulatory to protect the eye from microbial materials.
What is the reason of Dry eye?
Amount of tear decreases as we age. It is mostly seen in elder woman but it can be seen at any age and gender. It may develop rarely due to the lackness of vitamin A in undeveloped countries. There might be other reasons too. If patient have articular pain beside dry eye, Sjögren Syndrome might be the reason. Some medicines reduce tear and it might cause dry eye. These medicines are:
- Beta Blockers
If patients need to take this medication they might use artificial tear drop. People who have dry eye are more able to get side effect for artificial tear drop with toxic. Some eye drops can contain protectable materials so it may irritate the eye.
How to diagnosis dry eye?
Any ophthalmologists can diagnosis dry eye but they have to run tear calculation test for accurate result.
Schirmer Test: A filter tissue placed under eye lid and it calculates if tear is enough or not. Tear should be less than 10 mm to be dry eye.
Tear film break-up time: Colorant drop under eye lid and blink couple times and wait 10 seconds without blink to see if there are any dry spots. It is important for diagnosis.
1- Tear adding
Artificial tear drops which are very similar to tears must replace the deficient amount of tear. They both moisturize the eye and keep wet. There are many different kinds of artificial tear drop. Patients who use contact lens and are sensitive for preservative substance should use non-preservative eye drops. Artificial eye drops are used few times a day. Patient should follow doctor’s instruction.
2- Permanent and temporary punctum(plug)
There is other way to keep the eyes moisturized and provide lacrimation. It is aplied to keep the existing tear. Tears leak into the nose thru ducks in our nasal system. (When we cry our nose also leak.) We can block those ducks temporarily or permanently to keep tear and artificial tear in the eye long time.
3- Other Techniques
Tears also evaporate as same as other liquids. It can be useful to keep our home or room humid to prevent evaporation so a cup of water placed on the top of stove or heater in winter. Person who have dry eye should protect their eyes from heat, steam also cigarettes smoke. Eye drops that contain vitamin A are useful for Stevens Johnson syndrome and pemphigoid.