Mitsch C, Pemp B, Pollreisz A, et al. - Among patients with diabetic macular oedema (DME) and patients with choroidal neovascularization (CNV) due to age-related macular degeneration, researchers examined the short-time impact of intravitreal injections (IVI) of the vascular endothelial growth factor inhibitors ranibizumab and aflibercept on retinal arterial and venous oxygen saturation (SO2a and SO2v), arteriovenous oxygen saturation difference (AVD) and vessel diameter (VDa and VDv). Using a retinal oximeter before and minutes after IVI of ranibizumab or aflibercept, retinal vessel oxygen saturation and diameters were assessed. The analysis included 40 eyes with CNV and 34 eyes with DME. During the physiological stress after an IVI, the observed changes could be interpreted as signs of increased metabolic demand. The abnormal arterial constriction and the abolished rise in AVD seen with DME only in the eyes suggest an impairment of vascular autoregulation and delivery of oxygen and a decreased neuroretinal metabolism in the diabetic retina shortly after IVI with a significant impact on inner retinal oxygen consumption.