Ineffective eye drop instillation poses increased risk to glaucoma patients. Photo: Getty.

Researchers recently found that ineffective self-installation of eye drops was associated with an increased risk of glaucoma progression and treatment advancement to incisional surgery.

In a previous study, video recordings of eye drop self-instillation by patients with glaucoma or ocular hypertension were graded as effective or ineffective depending on whether the patient successfully instilled at least one drop on the right ocular surface. Glaucomatous progression was then retrospectively defined as retinal nerve fiber layer (RNFL) thinning as measured by either optical coherence tomography (OCT), visual field (VF) progression or need for incisional glaucoma surgery as determined by a glaucoma specialist unaware of patient performance in the eye drop instillation study. Subjects with at least two follow-up OCT or VF studies were included in the current study. Sufficient follow-up data was available for 101 patients.

 Eighty-eight patients (87.1%) were effective in eye drop instillation at baseline. Mean follow-up was 5.1 years, during which time 73 patients (72.3%) experienced progression or underwent incisional surgery in either eye. All patients in the ineffective group progressed or underwent incisional surgery, while only 68.2% of the effective group met this criteria. Kaplan-Meier survival analyses showed significantly faster time to reaching an endpoint in the ineffective group. There was no difference in age, baseline intraocular pressure or baseline RNFL thickness between the groups.

“Our exploratory, retrospective study indicates an association between baseline eye drop instillation efficacy and long-term progression of glaucoma, as measured by RNFL thinning on OCT, worsening VF deficits or advancement to incisional glaucoma surgery,” the study authors concluded in their paper. “Identifying patients who are ineffective at instilling eye drops and providing education on eye drop instillation techniques may lead to better outcomes.”