Eye drop instillation technique in patients with glaucoma

To evaluate the technique of eye drop instillation in patients with glaucoma and assess factors associated with a good technique.

A cross-sectional observational study of 85 participants using self-administered topical medication for glaucoma or ocular hypertension. Patients were asked to demonstrate how they normally instil eye drops using a 5-ml bottle of sterile artificial tear solution. The procedure was recorded and assessed by two masked graders. Whether the patient had been previously shown how to instil drops, the number of eye medications used, and self-perceived difficulty of using drops were also recorded. Univariable logistic regression was performed to relate each variable to drop technique and variables with P<0.2 were included in a multivariable logistic regression analysis.

54.1% (46/85) of patients had a poor drop technique, 11.8% (10/85) missed the eye, 15.3% (13/85) touched the tip of the bottle to the bulbar conjunctiva or cornea, and 27.1% (23/85) touched the eyelid or lashes with the bottle tip. 81.2% (69/85) could not recall being shown how to instil eye drops. In the multivariable model, previous instruction regarding drop instillation technique was significantly associated with good technique (adjusted OR=8.17, 95% CI 2.02-33.05, P=0.003) and increasing age was associated with poor technique (adjusted OR=0.95, 95% CI 0.91-0.99, P=0.017).

Education relating to eye drop instillation technique is significantly associated with a patient's ability to instil drops correctly. The assessment of a patient's ability to instil eye drops correctly should be a routine part of the glaucoma examination.