Abstract
Purpose: :
Vascular endothelial growth factor (VEGF) plays a central role in the development of choroidal neovascularization. Its blockade by intravitreal injection of anti-VEGF monoclonal antibodies, ranibizumab and bevacizumab, has become the standard of care in the treatment of exudative age-related macular degeneration (ARMD). Among its numerous functions, VEGF is a recognized retinal neurotrophic factor. Recent literature has suggested that VEGF plays a critical role in the maintenance and function of adult mouse retinal cells and that systemic neutralization of VEGF results in neural toxicity1. The aim of this study is to investigate for evidence of retinal toxicity in patients receiving intravitreal injections of bevacizumab and/or ranibizumab for the treatment of exudative ARMD.
Methods: :
A cross-sectional analysis of 34 consecutive patients with exudative ARMD in one eye only receiving bevacizumab and/or ranibizumab injections. All patients were subject to strict exclusion criteria. Data was collected on the following functional parameters: photopic and scotopic a- and b-wave amplitudes and implicit times measured by Ganzfeld electroretinography; nasal retinal thickness on spectral-domain Optical Coherence Tomography (OCT), and visual field surface area of Goldmann visual field (I4e, III4e, and IV4e isopters). A comparison of parameters was made between injected and non-injected (control) eyes of each subject
Results: :
Seventy-two eyes of 34 patients were included in the study. Paired Student’s t tests revealed no statistically significant difference in Ganzfeld electroretinography, OCT or Goldmann visual field parameters of injected and non-injected (control) eyes.
Conclusions: :
While VEGF blockade has been linked to retinal toxicity in the mouse model, no such toxicity was detected in analogous functional parameters of human subjects.1. Saint-Geniez, M, PloS One. 2008;3(11):e3554.Epub 2008 Nov 3
Keywords: age-related macular degeneration • ocular irritancy/toxicity testing • injection