How Do We Know If We Have Dry Eye Disease?

Segment 5

The components and importance of a good DRY EYE EXAM.

How does my doctor determine the health of these tear/oil glands? Symptoms of dry eye cause the dry eye specialist to look harder than most and they will have equipment to image these glands to see how constipated and/or withered they look. Testing how long a tear holds together before dry spots from evaporation occur and testing salt levels in the tear are both good ways to see how dysfunctional these oil glands are.

Pressing on the lids while looking with magnification allows dry eye specialists to see how much - and what kind of - oil comes out of a gland. Their best performance is thin clear “salad dressing“ oil pouring out with very little pressure. More common is scant, thick, milky or toothpaste-like oils or even as wax. Worst is nothing coming out even with heavy pressure squeezing the lid.

Advanced technologies or careful magnified exams can help us see and/or image how patients blink, so we can see how well - or, more commonly, how poorly the lids come together and then to see and/or image the amount of oil being produced by those blinks.

Since we know there are other causes for Dry Eye disease, other than dysfunctional oil glands, a good exam will also include looking at the volume of tears produced by the “sprinkler system” and if suspected, the function of the “firehose.” This can involve small test tapes or threads, designed to soak up the new tears made over a five minute time frame, as well as to measure the volume resting on the lower eyelid.

Tests for inflammation can involve dipstick test strips or red scale measurements and a special, in-office Lab test can measure salt levels. A good dry eye specialist will also look at the surface and under-surfaces of the eyelids, the lashes and eye’s surfaces - as well as testing with dyes as part of a complete dry exam in order to determine what other issues may be involved.