Abstract
Purpose :
To evaluate the effect of topical ocular hypotensive agents on OCT angiography (OCTA).
Methods :
We conducted a prospective case-control study by enrolling one eye per participant. We recruited healthy individuals 21 years or older with no eye conditions. Exclusion criteria comprised refractive error > +3.00D or < -7.00D, abnormal optic disc appearance, intraocular pressure (IOP) > 21 mmHg, or any contraindications to the medications. Baseline OCTA images, IOP, pulse rate, and blood pressure were taken. The participants were then randomized to different orders of medications, including latanoprost, timolol, dorzolamide, brimonidine, and netarsudil. The participants were instructed to instill one eyedrop prior to their study visit based on the half-life of the medication (1 night and 6 hours for timolol, dorzolamide, or brimonidine; 12 hours for latanorprost; 6 hours for netarsudil). A minimum washout period of two-week between each medication was used. We compared the changes in nerve fiber layer plexus-capillary density (NFLP-CD) before and after the use of medications, as well as changes IOP, pulse, and blood pressure.
Results :
We enrolled 17 eyes from 17 participants. The IOP exhibited a statistically significant decrease before and after the medications: dorzolamide (mean change± standard error: -2.2±0.4mmHg, p<0.001), netarsudil (-2.5±0.5mmHg, p<0.001), brimonidine (-2.6±0.7mmHg, p=0.002), latanoprost (-3.1±0.7mmHg, p=0.001), and timolol (-3.1±0.6mmHg, p<0.001). However, no significant changes were observed in NFLP-CD before and after the medications: dorzolamide (+0.24±0.21% area, p=0.306), netarsudil (+0.29±0.23% area, p=0.238), brimonidine (+0.18±0.28% area, p=0.517), latanoprost (-0.02±0.29% area, p=0.956), and timolol (+0.18±0.31% area, p=0.572). No significant difference in pulse rate and blood pressure was observed after the administration of the medications.
Conclusions :
Ocular hypotensive medications do not directly affect ocular circulation as measured by NFLP-CD. This finding helps validate the use of NFLP-CD as a metric to monitor disease progression and therapeutic effects without the concern of being biased by the direct effect of glaucoma eye drops that the patient might be using. Further study is needed on the medications’ short-term and long-term effects on NFLP-CD in glaucoma patients.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.