purpose: to determine the frequency of risk factors for retinal vein occlusion (rvo) in patients referred to a private clinic in rasht during 1995-2001. methods: this cross-sectional study was conducted on all patients with rvo who were referred to the clinic. sex, age, hypertension (htn), cardiovascular diseases (cvd), diabetes mellitus (dm), hypercoagulable states, glaucoma, smoking, hyperlip...