Electronically Monitored Corticosteroid Eye Drop Adherence after Trabeculectomy Compared to Surgical Success

Purpose: To compare electronically measured adherence with topical corticosteroid (CS) drops with outcomes of glaucoma surgery. Design: This prospective cohort study included eyes undergoing surgery from August 2019 to January 2021 and followed for up to 1 year. Participants: All patients were recruited from the Glaucoma Center of Excellence at the Wilmer Eye Institute, Johns Hopkins. Eligible patients had primary open-angle or angle-closure glaucoma, were aged ≥18 years, and underwent trabeculectomy (with or without cataract surgery) or tube-shunt implantation. Methods: Patients were instructed on the use of an eye drop monitoring device (Kali Drop), with the knowledge that it would be used to record postoperative CS instillation in real time. Main Outcome Measures: Adherence to a regimen of CS eye drops during the first 5 postoperative weeks; achievement of target intraocular pressure (IOP) at 6 weeks and 6 months to 1 year after surgery; and bleb morphology at 1 year. Results: Among 90 patients, adherence was 89.7% ± 13.7% overall and 80.9% ± 15.8% during dosing every 2 hours. Target IOP was achieved at the final visit (6 months or 1 year) in 81% (59/73) without reoperation. Eyes with a higher ratio of drops taken versus prescribed were significantly more likely to achieve target IOP at 6 months/1 year (P = 0.05). Total adherence was better in younger persons, eyes with less field loss, and patients of one particular surgeon (P < 0.03). Percent adherence during dosing every 2 hours was higher in eyes with higher target IOP (P = 0.01). No adherence outcome was significantly related to race, sex, bleb morphology, postoperative pain, or postoperative anterior chamber inflammation. Adherence values did not significantly correlate with adherence questionnaire data (predicted mean = 78% ± 17%, actual mean = 91% ± 13% adherent, P < 0.001). Conclusions: Adherence to frequent postoperative eye drops was high and can be successfully monitored remotely. Surgical success was greater among eyes with nearly ideal adherence and was poorer in older persons and those with more advanced glaucoma.