Abstract
Purpose:
To evaluate the efficacy of biweekly alternate intravitreal bevacizumab and ranibizumab dosing for choroidal neovascularization (CNV) in age related macular degeneration (AMD), relcalcitrant to prior monthly dosing of intravitreal anti-vascular endothelial growth factor (VEGF) therapy.
Methods:
Review of AMD patients (identified after exclusion of other causes of CNV) with persistent or increased subretinal (SRF) or intraretinal fluid (IRF) fluid on spectral-domain OCT (SD-OCT) despite ≥12 previous monthly intravitreal bevacizumab or ranibizumab injections who were switched to biweekly alternating intravitreal 1.25mg bevacizumab and 0.5mg ranibizumab.
Results:
Five eyes of five patients (mean age 80.6 ± 5.8 years) with recalcitrant AMD who had received an average of 39±8.2 prior ranibizumab or bevacizumab injections were included. BCVA, SD-OCT central subfoveal thickness (CFT) and macular volume (MV) were evaluated at baseline and at each subsqeuent biweekly treatment. The baseline BCVA was 0.52±0.07 logMAR, CFT μm was 413±150.7 (312-674 μm) and MV was 7.6±0.7mm3 (6.83-8.58mm3). After an average of 13.4±6.6 (range 6-21) alternating biweekly ranibizumab and bevacizumab injections, mean logMAR BCVA was 0.42±0.09 (p=0.14). Mean CFT (383.4±169.4μm, p=0.32) and mean MV (5.8±1.08mm3, p=0.98) remained unchanged. One patient in our series was previously treated with photodynamic therapy (PDT) with verterporfin. Among the four remaining eyes without prior PDT treatment, there was a significant improvement in BCVA from 0.52 to 0.38 logMAR (p=0.006), reduction in mean CFT (413.5 to 359.25 μm,p=0.009) and MV (7.65 to 7.22mm3, p=0.059). Detailed SD-OCT analysis of pigment epithelial detachment (PED) height and SRF on these 4 patients showed a significant reduction in maximum PED height from 304.25±174.82 μm to 253.75±148.15 μm (p=0.04) and maximal SRF height from 200±67.21 μm to 107.25±30.13 μm (p=0.02).
Conclusions:
Biweekly alternate intravitreal ranibizumab and bevacizumab resulted in an overall maintained BCVA, CFT and MV in recalcitrant neovascular AMD with significant visual and anatomical improvement in eyes that had not undergone prior PDT. This may an alternative therapeutic strategy in these difficult to manage recalcitrant cases.
Keywords: 412 age-related macular degeneration •
688 retina •
748 vascular endothelial growth factor