Epimacular brachytherapy for the treatment of retinal angiomatous proliferation.

Purpose: The purpose of this study was to present a case of a retinal angiomatous proliferation (RAP) treated with epimacular brachytherapy that was refractory to continued ranibizumab therapy.

Patients: An interventional case report of an 89-year-old woman with angiographically confirmed RAP had shown a poor response to 8 anti-vascular endothelial growth factor (anti-vascular endothelial growth factor) retreatment injections over a 10-month period.

Methods: The patient underwent pars plana vitrectomy combined with beta irradiation of the RAP lesion using a Strontium-90 applicator (NeoVista). The device was positioned over the lesion to deliver 24 gray over 4.5 minutes. Early Treatment Diabetic Retinopathy Study best-corrected visual acuity with full refraction was undertaken monthly by trial-certified examiners, independent of the operating surgeon. The main outcome measures were Early Treatment Diabetic Retinopathy Study best-corrected visual acuity, central retinal thickness measured by optical coherence tomography, and the number of anti-vascular endothelial growth factor retreatments.

Results: Preoperative best-corrected visual acuity was 53 letters (20/80), improving to 69 letters (20/50) at 12 months and 71 letters (20/40) at 21 months. Only one ranibizumab retreatment was required, at Month 2. Optical coherence tomography central retinal thickness reduced from 312 μm to 224 μm with a return of the normal foveal contour. There was full regression of the RAP lesion on clinical examination, with a reduction in lesion activity demonstrated by fundus fluorescein angiography.

Conclusion: This is the first reported case of RAP treated with epimacular brachytherapy, with encouraging results. Epimacular brachytherapy may be a new treatment option for refractory RAP lesions requiring frequent intravitreal ranibizumab, but further studies are needed.