Long-term Choroidal Vascular Changes after Iodine Brachytherapy versus Transpupillary Thermotherapy for Choroidal Melanoma

Abstract

Purpose To compare long-term choroidal vascular changes after iodine-125 brachytherapy (IBT) versus transpupillary thermotherapy (TTT) used as primary treatment of small choroidal melanoma. Methods Ninety-five small choroidal melanomas were randomized: 49 eyes with TTT and 46 eyes with IBT alone. Fluorescein and indocyanine green angiography (ICGA) were performed at 3-month intervals during the first year, and every 6 months thereafter. Results Mean follow-up was 56.2 months (range, 24–118 months; SD, 22.6). Tumor regressed in 45 (92%) TTT-treated vs 45 (98%) IBT-treated eyes (p=0.397). Four TTT-treated and one IBT-treated tumor recurred. Occlusion of choriocapillaris was present in all TTT and IBT cases. Closure of medium and large choroidal vessels was observed in 17 (35%) TTT-treated vs 44 (96%) IBT-treated eyes (p<0.001). Choroidal vascular remodeling was detected in 20 (41%) TTT-treated and 16 (35%) IBT-treated eyes (p=0.693). Retinochoroidal anastomosis was present in 4 of the 37 (11%) TTT-treated eyes with patency of medium and large choroidal vessels, but never observed in the IBT-treated eyes, and was associated with tumor recurrence. Among IBT-treated eyes, segments of choroidal vascular wall ICG staining and choroidal aneurysmal changes were detected in 30 (65%) and 7 (15%), respectively. These changes were never detected in TTT-treated cases (p<0.0001 and p=0.015, respectively). Conclusions The pattern of tumor choroidal vascular changes following IBT and TTT differs. TTT is less effective in closing all tumor vasculature. The role of long-term choroidal vascular remodeling observed after these two treatments needs longer follow-up.