Choroidal thickness after intravitreal ranibizumab injections for choroidal neovascularization

PURPOSE To study changes in choroidal thickness with ranibizumab treatment for choroidal neovascularization (CNV). DESIGN Prospective case series. METHODS This prospective study consisted of 60 CNV-affected eyes of 60 patients treated with intravitreal injections of ranibizumab using an on-demand protocol after an initial loading phase. The eyes studied included 20 with age-related macular degeneration (AMD), 20 with polypoidal choroidal vasculopathy (PCV), and 20 with myopic CNV. In the eyes with AMD and PCV, choroidal thickness at the fovea was measured with optical coherence tomography using enhanced depth imaging. In eyes with myopic CNV, the choroidal thickness was measured using standard optical coherence tomography without the enhanced depth imaging technique. RESULTS With ranibizumab treatment, central retinal thickness decreased significantly (P < 0.001) and visual acuity improved significantly (P < 0.001). However, central choroidal thickness (167.2 ± 108.3 μm) showed no significant change at 1 month after the loading phase (165.2 ± 107.8 μm, P = 0.120) or at final examination (164.8 ± 107.7 μm, P = 0.115). At baseline, central retinal thickness in eyes with AMD was significantly greater that those with PCV (P = 0.005) or high myopia (P = 0.029). However, central choroidal thickness in eyes with myopic CNV was significantly thinner than in eyes with AMD (P < 0.001) or PCV (P < 0.001). In each type of disease, there was no significant change in central choroidal thickness with ranibizumab treatment. CONCLUSION The effect of ranibizumab on the choroidal thickness is minimal, if any.