Assessment of eye drop instillation technique in patients with glaucoma: a hospital-based cross-sectional study in...

To objectively and subjectively assess eye drop instillation in patients with glaucoma, and identified factors associated with eye drop instillation failure.

This cross-sectional observational study included patients who visited an outpatient clinic between August and November 2023. Patients were objectively assessed by observing a demonstration, and subjectively assessed through interview responses.

A total of 187 individuals diagnosed with glaucoma participated, with an average age of 63.1 ± 10.5 years. During the demonstration, 84.5% of participants succeeded in squeezing at least one drop in the eye; however, only 68 patients (36.4%) were classified as having instillation success. The objective and subjective evaluations were inconsistent in 80 of 187 patients (42.8%) and the deviations mainly included the following steps: wash hands (55.6% vs. 85.6%, P < 0.001), squeeze one drop (62.0% vs. 84.5%, P < 0.001), drip into the pocket (84.5% vs. 68.4%, P < 0.001), avoid tip touches adnexa or ocular surface (51.9% vs. 69.0%, P = 0.001), gently close eyes (50.8% vs. 84.0%, P < 0.001), performs nasolacrimal occlusion (18.7% vs. 44.4%, P < 0.001), not blinking frequently after eye drop instillation (39.0% vs. 65.2%, P < 0.001). Multivariate analysis revealed that factors associated with instillation failure included older age (P = 0.02), binocular disease (P = 0.03), residential status of living alone (P = 0.001), and self-reported difficulty (P = 0.03).

Patient self-reports did not accurately reflect their eye drop techniques. Thus, incorporation of more diverse eye drop assessment methods and educational tools for patients with glaucoma is necessary. Physicians can identify patients in need of guidance by assessing risk factors for eye drop instillation failure rather than solely relying on patient reports.