Dynamic indocyanine green angiography-guided focal thermal laser treatment of fibrotic choroidal neovascularization

Purpose: Fibrotic choroidal neovascular membranes (CNV) are the end-stage outcomes of neovascular age-related macular degeneration (AMD). No treatment is currently available for fibrotic CNV. We investigated the role of focal thermal laser ablation of the perfusing afferent arteriole as determined by dynamic indocyanine green angiography (ICGA). Methods: We conducted a retrospective study of 20 patients with fibrotic CNV associated with significant subretinal fluid or retinal edema, who also demonstrated well-defined perfusing arterioles by dynamic ICGA. Patients underwent focal thermal laser occlusion of the perfusing afferent arteriole. Six, 12 and 24 weeks post-treatment, eyes underwent repeat examination with optical coherence tomography (OCT) and visual acuity testing, and ICGA at 12 weeks. Results: Therapeutic closure of the perfusing afferent arterioles was achieved in 17 of 20 eyes immediately post-treatment. All 17 of these eyes demonstrated significant resolution of retinal edema and subretinal fluid, as evidenced by OCT, which was dramatic in some cases. Seven eyes demonstrated an improvement in visual acuity of 1 line or more. While most eyes demonstrated reperfusion within 3 months, many lesions suggested reduced vascularity and flow. Conclusion: Eyes with fibrotic CNV and associated retinal edema often demonstrate well-defined vascularity of the fibrosis with discrete perfusing arterioles when imaged by dynamic ICGA. Thermal laser occlusion of these arterioles can result in resolution of subretinal fluid, and occasionally an improvement in vision. This represents a potential therapeutic intervention for an advanced stage of AMD currently regarded as stable.