My Eyes Water...They Can't Be Dry
Dry eye is one of the most challenging conditions for both patients and doctors to manage. Nearly 30 million Americans suffer from dry eye. However, less then half of these patients are actively treated for dry eye.
Why are so many patients with dry eye untreated?
The answer probably lies in the fact that some of the signs and symptoms of dry eye do not match the name of the disease DRY EYE. Two of the most common symptoms of dry eye are watery or tearing eyes and fluctuations in one’s vision. Most patients don’t correlate eyes that are constantly tearing with a condition labeled dry eye. They also don’t correlate the symptom of having to stop reading their book due to their vision blurring after a few minutes with a condition labeled dry eye.
Let’s break down these two symptoms.
Why do my eye water if they are dry? That does not make sense. First, let’s breakdown the tear film that coats and lubricates our eyes. It is redistributed over the surface of the eye with each blink. It is essentially an emulsion made up of an oily component from glands that line our upper and lower lids, a mucus component from cells on the white part of the eye and the watery component from the lacrimal gland located above the eye. When there is a breakdown in our tear film, the first thing the body wants to do is cover this deficit. The quickest and easiest way for the body to do this is to produce more of the watery component of the tear film. Unfortunately, this increased production of the watery component is matched with an increased production of the oily and mucus components of the tear film, as they cannot be produced as quickly. The oily and mucus components of the tear film are responsible for the tear film not evaporating too quickly and it sticking to the surface of the eye. When the normal composition of the tears is disrupted, resulting in the production of more of the watery component of the tear film, these tears now don’t stick to the surface of the eye like they normally do resulting in the tears pooling in the corners of the eye...water eyes.
If my vision blurs while reading or watching television, I must need a change in my glasses or contact lens prescription. Not so fast. If you see clearly when you start to read and then it blurs or you notice that sometimes everything you see is really clear and other times it is blurry, simply changing your glasses will likely not fix the problem. Let’s think about it. If your glasses prescription changes after a period of reading or fluctuates throughout the day, there would always be times that your glasses didn’t work regardless of the prescription in the lenses. What is in fact occurring during these fluctuations in one’s vision is a breakdown in the quality of the tear film on the surface of the eye. The tear film is the first thing that starts to focus the light rays as they travel through the eye to be focused as a clear image on the retinal tissue in the back of the eye. With each blink, this tear film is redistributed evenly over the surface of the eye. If this tear film breaks down after periods of reading or looking at the computer, the result is blurred vision after it breaks down.