TWELVE-MONTH SAFETY AND VISUAL ACUITY RESULTS FROM A FEASIBILITY STUDY OF INTRAOCULAR, EPIRETINAL RADIATION THERAPY FOR THE TREATMENT OF SUBFOVEAL CNV SECONDARY TO AMD

Purpose: The purpose of this study was to evaluate the short-term safety and feasibility of intraocular, epiretinal delivery of beta radiation for the treatment of subfoveal choroidal neovascularization secondary to age-related macular degeneration for 12 months. A 3-year follow-up period is planned to assess the long-term safety of the procedure. Methods: In this nonrandomized, multicenter feasibility study, 34 treatment-naive patients with predominantly classic, minimally classic, or occult lesions due to subfoveal choroidal neovascularization secondary to age-related macular degeneration received a single treatment with either 15 Gray (Gy) (8 patients) or 24 Gy (26 patients) beta radiation (strontium-90) using a novel intraocular delivery device. Adverse events and safety end-points were observed and recorded. Visual acuity was measured preoperatively and postoperatively using standard Early Treatment Diabetic Retinopathy Study vision charts. Results: Twelve months after treatment, no adverse events associated with exposure to radiation were observed. All patients in both 15 Gy (n = 4) and 24 Gy cohorts (n = 17) who met inclusion criteria and were treated according to protocol lost fewer than three lines of vision. Fifty percent (2/4) of the 15 Gy-treated patients and 76% (13/17) of the 24 Gy-treated patients improved or maintained their visual acuity at 12 months. In the 24 Gy group, 29% (5/17) gained three lines or more in visual acuity. The mean change in visual acuity observed at month 12 was +10.3 letters in the 24 Gy study cohort and -1.0 letters in the 15 Gy cohort. Conclusion: The short-term safety and efficacy of intraocular, epiretinal delivery of beta radiation for the treatment of subfoveal choroidal neovascularization was promising in this small study group and should be studied in a larger cohort of patients.