Tear Meniscus Imaging by Anterior Segment-optical Coherence Tomography in Medically Controlled Glaucoma

Purpose: To investigate the tear meniscus (TM) in medically controlled glaucoma patients (MCGP) using Anterior Segment-Optical Coherence Tomography (AS-OCT). Methods: Fifty-six MCGP, twenty-four patients with evaporative dry eye (EDE), and thirty healthy subjects (Controls), were enrolled. MCGP were divided into Group 1 (14 eyes): ß-blockers; Group 2 (14 eyes): prostaglandin analogs; Group 3 (28 eyes) ≥2 drugs. Ocular Surface Disease Index (OSDI) questionnaire, tear film break-up time (TBUT), corneal fluorescein staining (CFS), Schirmer Test I (STI), and tear meniscus height (lower and upper: L-TMH, U-TMH) and area (L-TMA, U-TMA) using AS-OCT, were performed. Results: OSDI score was higher (P<0.05) in EDE and Group 3 compared Groups 1, 2 and Controls. No significant differences were found between Group 3 and EDE for all clinical parameters. L-TMA was significantly lower in Groups 1-3 (P<0.05) and EDE (P<0.001) compared to Controls, and lower in Group 3 and EDE compared to Groups 1 and 2 (P<0.05). L-TMH was lower in Groups 1-3 and EDE compared to Controls (P<0.001), and in EDE and Group 3 compared to Groups 1 and 2 (P<0.05). U-TMA was lower in EDE and MCGP Groups compared to controls (P<0.05). L-TMA and L-TMH negatively correlated with OSDI score (P<0.01, r=-0.379; and P<0.01, r=-0.352, respectively). Conclusions: AS-OCT permits a non-invasive and reliable tear meniscus imaging in medically controlled glaucoma, depicting the glaucoma-related-OSD (GR-OSD) as a dry eye disease-like condition. Thus, reduced values of tear meniscus height and area can be proposed as structural indicators of glaucoma therapy-related ocular surface disease.