It is a blockage of this vessel by a thrombus, which causes painless loss of vision, which varies from mild to severe and is usually of sudden onset. The diagnosis is based on ophthalmoscopy.

Treatments: anti-vascular endothelial growth factor drugs (eg, ranibizumab, pegaptanib, bevacizumab), intraocular injection of a dexamethasone or triamcinolone implant, and laser photocoagulation.