Abstract
Purpose :
Intravitreal dexamethasone implants are indicated for the management of macular edema (ME) due to retinal vein occlusions (RVO). Most studies are unclear on factors affecting long term outcome. This retrospective observational study aims to identify factors that could determine BCVA in eyes receiving ≥6 implants.
Methods :
8 eyes previously treated with ≥3 anti VEGF injections and subsequently ≥6 intravitreal dexamethasone implants (Ozurdex, Allergan, Irvine, CA) were included. Factors evaluated included the BCVA, IOP, duration of symptoms, systemic status, macular perfusion, number of injections, treatment intervals, additional intervention. OCT features included central macular thickness (CMT), vitreomacular interface abnormalities, intraretinal cystoid spaces, schisis, subfoveal detachment and atrophy of the RPE-photoreceptors.
Results :
8 eyes (4 CRVO, 4 BRVO) received mean 7.35 injections( range 6-10). Age ranged from 39-75 years. Systemic co morbidities included systemic hypertension( 8), diabetes mellitus( 6), bronchial asthma (1) and ischemic heart disease(2). BCVA (LogMAR) ranged from 0.18 to 1.48 . 2 eyes were pseudophakic. IOP ranged from 11-19 mm Hg (2 on medication). Mean CMT was 706.125 μ (range 368-1120 μ). SDOCT features included intraretinal cystoid spaces (8 eyes), subfoveal detachment (6 eyes) and vitreoretinal interface abnormalities (4 eyes). During the period of the study, all phakic eyes underwent uneventful phacoemulsification with IOL (1 with PPV and ERM removal, 2 with dexamethasone implant). Laser photocoagulation was performed in 2 eyes ( macular grid, PRP) IOP rise was seen in 3 eyes . Mean interval between injections was 7, 6.125, 5.25, 5 and 5.25 months for the first 6 injections. Maximum BCVA gain was seen after the first injection. At final followup BCVA improved in 2 eyes, was maintained in 1 eye and reduced in 5 eyes. Mean final CMT was 397.857 μ (range 64-829 μ). ERM with intraretinal schitic spaces and RPE -photoreceptor atrophy were OCT features seen in eyes that lost baseline vision .
Conclusions :
≥6 intravitreal dexamethasone implants in antiVEGF resistant ME in RVO have modest effect in maintaining or improving long term BCVA . Progression of cataract is seen in all eyes. Maximum BCVA gain is seen after the first injection and rarely after the third. ERM, schitic spaces and RPE-photoreceptor atrophy are seen on OCT in eyes with poor final BCVA.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.