Abstract
Purpose:
To examine the visual acuity (VA), central macular thickness (CMT), intraocular pressure (IOP), and adverse events following intravitreal dexamethasone implant for the treatment of center-involving macular oedema in central and branch retinal vein occlusion (CRVO & BRVO), using an as-required injection regimen.
Methods:
A retrospective case-note review of 21 eyes of 21 consecutive patients who underwent one or more intravitreal injections of 700μg dexamethasone implant (Ozurdex, Allergan, Inc., Irvine, CA) for the treatment of macular oedema due to CRVO (n=7) or BRVO (n=14). Eligibility criteria consisted of minimum follow-up of 12 months and16 weeks after the first and second injections, respectively. Patients with a diagnosis of glaucoma were excluded from treatment. Re-treatment criteria consisted of a loss of logMAR VA of >=5 letters, associated with CMT of >250μm.
Results:
After the first injection, logMAR VA was either stable (0 to 14 letters gain) or improved by >=15 letters in 66.7%, 66.7%, 71.4%, 66.7% and 52.4% of eyes after 2 weeks, 8 weeks, 16 weeks, 6 months and 12 months, respectively. 10 eyes (47.6%) received a second injection after a median follow-up of 20.9 weeks (18-40 weeks). After the second injection, VA improvement or stability occurred in 80%, 70%, 40% of patients after 2 weeks, 8 weeks and16 weeks, respectively. VA loss of >=15 letters occurred in 3 eyes. Median change in LogMAR VA, however, was not statistically significant at any of the above time points. There was a significant reduction in median CMT at 2 weeks, 8 weeks, 16 weeks and 6 months (p<0.001, <0.001, 0.035 and 0.002; respectively). A significant rise in median IOP occurred only at 2 and 8 weeks (p=0.02 and 0.002; respectively). 11 eyes (52.4%) had a rise in IOP >25 mmHg, requiring medical treatment. 6 of 15 phakic eyes (40%) had progression of cataract, 5 of whom required surgery. Only 1 eye developed culture-negative endophthalmitis after the 2nd injection and recovered pre-injection VA at 16 weeks.
Conclusions:
Intravitreal dexamethasone implant given as-required appears to reduce macular thickness and stabilise or improve visual acuity in the majority of patients with retinal vein occlusion, predominantly within the first six months. It however may be associated with increased intraocular pressure, rate of cataract surgery and sterile endophthalmitis.
Keywords: 688 retina •
505 edema •
561 injection