Abstract
Purpose :
To compare the anatomical and functional outcomes of intravitreal dexamethasone implant to those of oral carbonic anhydrase inhibitor therapy in patients with cystoid macular edema (CME) secondary to retinitis pigmentosa (RP) over 12 months of follow-up.
Methods :
This is a multicenter, retrospective, propensity score matched study.
Patients affected by RP complicated by CME with a central retinal thickness value of at least 350 μm were enrolled in the present study. Patients in cohort 1 received dexamethasone implant at baseline. Retreatment was permitted if central retinal thickness exceeded 350 μm. Minimum interval time needed for retreatment was 3 months. Patients in cohort 2 were treated with oral acetazolamide (500 mg/die). The two cohorts were matched through a propensity score method. Primary outcome measures were changes in central retinal thickness and best-corrected visual acuity (logMAR). Statistical analyses was performed using two-tailed comparison with Wilcoxon signed-rank test. Ocular and systemic side effects were recorded.
Results :
One-to-one matching according to the propensity score resulted in dexamethasone and acetazolamide arms containing 30 eyes each. As expected, groups were well balanced at baseline. Mean baseline central retinal thickness was 493 ±146 μm in the dexamethasone group and 479 ±121 μm in the acetazolamide group. Mean BCVA was 0.43 ±0.24 logMAR in the dexamethasone group and 0.41 ±0.20 logMAR in the acetazolamide group.
After 1 year of follow-up, CRT decreased on average by 286 μm in the dexamethasone group and 109 μm in the acetazolamide group (p<0.001). BCVA improved on average by -0.085 logMAR in the dexamethasone group and -0.041 logMAR in the acetazolamide group (p not sig). Mean number of injections in the dexamethasone group was 1.7 during one year of follow-up.
An intraocular pressure rise requiring topical treatment was recorded in 4 (13%) eyes in the dexamethasone implant group. One eye (3%) in the dexamethasone group required cataract surgery. No severe systemic adverse events were noted in either group.
Conclusions :
Intravitreal dexamethasone implant provides a superior anatomic improvement over oral carbonic anhydrase inhibitor therapy in patients affected by CME secondary to RP and therefore may represent a valuable treatment option.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.