Comparison of success rates in eye drop instillation between sitting position and supine position

Purpose To compare the success rates of eye dropinstillation in the sittingposition and supine positionamong Japanese patients with ocular diseases (cataract, glaucoma, or retinal and vitreous diseases). Methods Patients who were hospitalized in Okayama University Hospital for eye surgerywere studied. Instillation procedures of each patient in both the sittingand supine positionswere recorded using a video camera at the time of instillation. We defined “success” when one drop fell accurately onto the ocular surface at the first attempt. Instillation of two or more drops, drops delivered to a site other than the eye surface, and touching the eyelashes, eyelids, or conjunctiva with the tip of the eye dropbottle were regarded as “failure”. We excluded patients with vision below counting finger. Results One-hundred and two patients (54 males and 58 females, aged 70.2 ± 12.3 years) with ocular disease who were hospitalized for surgery (cataract: 61.8%, glaucoma: 15.7%, retinal and vitreous diseases: 22.5%) were included in this prospective observational study. The mean duration of eye dropuse was 3.1 ± 5.2 years. The success rate of eye dropinstillation was significantly higher in the supine positionthan in the sittingposition (64.7% vs. 50%, P = 0.0039). The mean age was significantly higher in the failure group than in the success group (74.0 ± 11.5 vs. 67.7 ± 12.4 years, P = 0.0085) for the sittingposition, but not significantly different for the supine position(72.3 ± 12.9 vs. 70.1 ± 12.0 years, P = 0.3849). No significant differences in mean duration of drop use, mean corrected VA, and mean spherical equivalent refraction were observed between success and failure groups, for both sittingand supine positions. Conclusions In the present study, the success rate of eye dropinstillation was significantly higher when applied in the supine positionthan in the sittingposition.