Efficacy and adherence to glaucoma treatment depending on eye drop application technique: A crossover randomized clinical trial

Purpose To compare patient education with a medical device as strategies to improve eye drop instillation in glaucoma patients and to assess their effects on intraocular pressure (IOP) control, treatment adherence, self-perceived competence, and observer-rated technique. Methodology In this randomized, crossover trial, 45 patients with primary open-angle glaucoma were assigned to group A (education only, n = 22) or group B (device, n = 23). After 60 days, the groups crossed over to the alternate intervention. IOP, ocular surface staining, treatment adherence, and instillation techniques were evaluated over 120 days using questionnaires and observer assessments. Results By the second assessment, mean right-eye IOP was lower with the device (15.8 mmHg vs. 20.1 mmHg; p < 0.05), and this reduction persisted after crossover. In contrast, the education group showed a nonsignificant trend toward worsening IOP ( p > 0.05), possibly influenced by baseline differences. Overall, the device achieved a 35% reduction in IOP compared with 23% for education alone. Adherence also improved markedly with the device: 71.1% of patients reported better compliance, versus only 2.2% in the education group (26.7% reported no change). Observer assessments supported these findings, with 91% of device users demonstrating correct instillation technique compared with 32% in the education group. Overdosing was more common in the education group (42% instilled more than one drop vs. 9% with the device). Patients additionally rated the device as easier and safer to use Conclusion The medical device outperformed education alone in improving instillation technique, IOP control, and treatment adherence while also reducing overdosing.