A significant therapeutic effect in the fellow eye after intravitreal ranibizumab injections was observed in a 39-year-old diabetic male. The patient was followed-up with fluorescein angiography (FA) and Optical Coherence Tomography (OCT). On referral, best-corrected visual acuity (BCVA) was 6/60 in the right eye and Counting Fingers in the left eye. FA revealed foveal leakage in both eyes. OCT revealed diabetic and cystoid macular edema (DME-CME) in both eyes. The patient was treated with two intravitreal ranibizumab injections in the left eye. BCVA was 6/15 and 6/30 one month after the last injection. OCT revealed significant improvement (DME elimination and significant CME improvement) in both eyes, despite the fact that only the left eye was treated. It is conceivable that, in this eye, chronic vascular damage was limited and a minimal quantity of ranibizumab had a positive effect on vascular permeability, resulting in DME resolution.