EFFICACY AND SAFETY OF TWO OR MORE DEXAMETHASONE INTRAVITREAL IMPLANT INJECTIONS FOR TREATMENT OF MACULAR EDEMA RELATED TO RETINAL VEIN OCCLUSION (SHASTA STUDY)

Purpose: To evaluate the efficacy, safety, and reinjection interval of dexamethasone intravitreal implant (DEX implant) in branch retinal vein occlusion and central retinal vein occlusion patients receiving >= 2 DEX implant treatments. Methods: Multicenter (26-site), retrospective chart review study. Data were collected from baseline (at first DEX implant) through 3 months to 6 months after last DEX implant. Results: Patients (n = 289) received 2 to 9 (mean, 3.2) DEX implants as monotherapy (29.1% of patients) or with adjunctive treatments/procedures. Mean duration of macular edema before first DEX implant was 18.4 months. Mean reinjection interval was 5.6 months. Mean peak change in best-corrected visual acuity from baseline through 4 weeks to 20 weeks after final DEX implant was + 1.0 line (P < 0.001). Best-corrected visual acuity and central retinal thickness improved significantly from baseline after each of the first 6 DEX implant injections (P <= 0.037); 59.7% of branch retinal vein occlusion and 66.7% of central retinal vein occlusion patients achieved >= 2-line best-corrected visual acuity improvement. Intraocular pressure increase (>= 10 mmHg) occurred in 32.6% of patients; 29.1% used intraocular pressure-lowering medication to treat increases associated with DEX implant. Only 1.7% of patients required incisional glaucoma surgery. Conclusion: Retinal vein occlusion patients treated with multiple DEX implant injections, either alone or combined with other therapies, had improved central retinal thickness and visual acuity with each subsequent injection. No new safety concerns developed with multiple implants.