Lipoprotein (a) promotes thrombogenesis by inhibiting the activation of plasminogen to plasmin. This can lead to an increased tendency for intravascular thrombin formation and fibrin deposition. Bandello and coworkers (cited in 1) found elevated lipoprotein (a) in 30% of patients with CRVO. These patients also had accelerated factor VII activation. Iijima and others (cited in 1) reported a patient with unilateral CRVO and ipsilateral cilioretinal artery occlusion with elevated lipoprotein (a) and familial dysplasminogenemia (reduced plasminogen activity without reduced plasminogen). Lip and coworkers (cited in 1) reported that patients with retinal vein occlusion had elevated blood pressure, plasma viscosity, hematocrit, hemoglobin, plasma fibrinogen, plasminogen activator inhibitor, and fibrin D-dimer as well as elevated serum lipoprotein (a) compared with controls.