Abstract
Purpose :
To assess the effects of brimonidine 0.15 % and pilocarpine 2% eye drops on angle configuration and miosis as measured using swept source optical coherence tomography (SS-OCT, CASIA SS-1000, Tomey Corporation, Nagoya, Japan) in primary angle closure suspects (PACS) with residual angle closure after laser peripheral iridotomy (LPI).
Methods :
This was a prospective randomised clinical trial (HSA CTC1400048) of 40 PACS who have previously undergone LPI but with ≥ 2 quadrants of residual appositional angle closure on gonioscopy. Subjects were randomized to either brimonidine 0.15% (BrGp - twice daily) or pilocarpine 2% (PilGp - four times daily) in one eye for one week. SS-OCT (128 scans) was performed at baseline, at 90 minutes after eye drop instillation, and at Week 1 to assess the effects of the medications on angle opening and miosis. The primary outcome measure was the difference in pupil diameter after one week of therapy. Secondary outcome measures include changes in measurement of anterior chamber (anterior chamber volume and depth), angle (trabecular iris angle, angle opening distance, trabecular iris space area, angle recess area) and iris parameters (iris thickness, iris curvature, iris volume).
Results :
Of 40 subjects recruited, 39 (BrGp, n = 20; PilGp, n = 19) completed the study. There was no difference in demographic, or baseline anterior chamber parameters in each group (all p>0.05, Table). There was no difference in intraocular pressure (IOP) reduction between groups at Week 1 (BrGp: Mean diff (SD): 1.9 ± 1.4 mmHg, PilGp: 1.0 ± 1.9 mmHg, p=0.1). PilGrp had significantly greater miosis than BrGp at 90 minutes (1.96 ± 0.21 mm vs. 1.01 ±0.27 mm, p<0.001) and Week 1 (1.90 ± 1.02 mm vs. 0.66 ± 0.45 mm, p<0.001). Only PilGp had wider angles at both 90 minutes and Week 1 (p<0.001, Table). BrGp had significantly increased iris volume (-0.65 ± 1.12 mm3 vs. 2.92 ± 1.69 mm3, p<0.001) at Week 1 compared to PilGp.
Conclusions :
In eyes with persistent angle closure after LPI, pilocarpine had greater miotic and angle opening effect than brimonidine, while brimonidine caused increase in iris volume. There was no difference in IOP reduction between treatment arms.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.