Comparison of the outcome of limited protocol Ranibizumab injection in naïve choroidal neovascular membranes secondary to pathological myopia versus age-related macular degeneration

Abstract

Aim We aimed to compare the anatomical and visual response of newly diagnosed choroidal neovascularization (CNV) secondary to pathological myopia or age-related macular degeneration with relatively poor initial vision to treatment with three intravitreal injections of ranibizumab. Patients and methods This prospective, comparative study included 29 eyes of 29 patients newly diagnosed with subfoveal active CNV, either secondary to age-related macular degeneration (AMD-CNV, 15 eyes) or to pathological myopia, that is, myopic CNV (MCNV, 14 eyes). All patients had an initial best-corrected visual acuity (BCVA) equal to or worse than 1.00 Log Mar. Patients received three intravitreal injections of 0.50 mg ranibizumab on a monthly basis. Patients were evaluated before injections and one month after each injection for BCVA and optical coherence tomography-measured retinal parameters: central macular thickness, total volume, and average thickness (AT). Amsler’s chart was used to detect scotomas and metamorphopsias. Results One month after the three injections, a significant improvement was noted in the two groups in central macular thickness, total volume, and AT. The improvement was significantly better in AT of the AMD group. The mean BCVA improved significantly in the AMD group only as patients either improved or remained stationary, whereas in the MCNV group, 21% of patients deteriorated, which affected the significance of the overall mean of improvement (P=0.7823); the difference in the overall mean was insignificant. Despite that, almost half of the patients in each group had their visual acuity improved by an average of 9.5 letters in AMD and 10.7 in MCNV. Conclusion Naïve AMD-CNV and MCNV of initially poor VA can get significant improvement in all optical coherence tomography-measured retinal parameters following a three-injection course of ranibizumab on a monthly basis. VA improvement is more predictable in AMD, as no patients deteriorated after the injections, yet the overall difference in VA improvement between groups was insignificant.