The objective of the study was to achieve maximum reduction in macular thickness in diabetic macular edema after single intravitreal Avastin injection as monitored by OCT which will allow for best results after laser application. This study was carried on 20 eyes with diffuse diabetic macular edema. All eyes received intravitreal injection of 1.25 mg of 0.05 ml avastin. BCVA and OCT central foveal thickness were done at baseline and at follow up visits 1, 2 and 3 weeks post injection.