 - Patients with a known history of retinal vein occlusion or central serous retinopathy, or predisposing factors to retinal vein occlusion RVO or central serous retinopathy CSR e.g. uncontrolled glaucoma or ocular hypertension, uncontrolled systemic disease such as hypertension, diabetes mellitus, or history of hyperviscosity or hypercoagulability syndromes 