Primarily, optometrists evaluate a patient’s tear meniscus because its height can be a sign of dry eye—if its height is less than 0.25mm, the patient might have dry eye.^1,2 But this fluid rim along the lid margin may also have implications for glaucoma patients, according to new research, and noninvasive technologies are making monitoring this easier than ever.

According to an Italian research team, anterior segment OCT (AS-OCT) measurements can show if a patient’s glaucoma medications are causing an ocular surface issue, such as dry eye disease (DED). The imaging technology permits noninvasive and reliable tear meniscus imaging in medically controlled glaucoma, the study says. “Reduced values of tear meniscus height and area can be proposed as structural indicators of glaucoma therapy-related ocular surface disease.”

The investigators looked at 56 glaucoma patients who were controlled with medication, 24 with evaporative dry eye and 30 healthy controls. The medically controlled glaucoma patient group was, itself, divided into three subgroups, 14 eyes were given ß-blockers, another 14 were given prostaglandin analogs and 28 were given two or more drugs. All were evaluated with an ocular surface disease index (OSDI) questionnaire, tear film break-up time (TBUT), corneal fluorescein staining, Schirmer Test I and AS-OCT evaluations of the upper and lower tear meniscus area and height.

They found the OSDI score was higher in the evaporative dry eye group and, from the medically controlled glaucoma group, those given two or more drugs. Those using more than one topical drug also had lower tear meniscus heights and areas than any other subset or participants. In fact, no significant differences were found between medically controlled glaucoma patients using more than one medication and evaporative dry eye patients using any of the clinical parameters applied. Upper tear meniscus area was lower in evaporative dry eye and all the medically controlled groups compared with the controls.