brvo and crvo risk factors in kermanshah

introduction: there are two basic types of vein occlusion, branch retinal vein occlusion (brvo), in which one of the branches of the main vein is blocked, and central retinal vein occlusion (crvo) in which the main vein of the eye is blocked.  vein occlusions are associated with various illnesses and often occur in elderly. the etiological causes of these diseases in the young people remained controversial.   the aim of this study was to investigate causes of central and branch retinal vein occlusion in young individuals. materials & methods: 20 patients (under 50 years old) with brvo and crvo were studied in kermanshah - iran during 1999-2003. they were referred to internal specialist for further systemic and metabolic assessment after having been diagnosed by ophthalmologist. results: the most common associated diseases found in these patients were hypertension,  hyperlipidemia and diabetes. there was no observation of any causes in one subject. brvo was found in 8 eyes (72.7%) with supratemporal involvement, one eye (9.1%) with inferonasal involvement, and four eyes (36.4%) with inferotemporal involvement, but no eye was found with superatemporal involvement. discussion: it was concluded that hypertension and hyperlipidemia are common causes in brvo and crvo diseases among young individuals in kermanshah.