Hyperhomocysteinaemia: risk of retinal vascular occlusion.

To investigate the possible relationship between hyperhomocysteinaemia and retinal vascular occlusion, we measured plasma homocysteine levels in 25 patients with a history of retinal vascular occlusion in the previous 2 years and in a control group of 24. The difference in mean plasma homocysteine levels was not statistically significant. All except 5 of the cases had hypertension, diabetes mellitus or hyperlipidaemia. Most of the patients had branch retinal vein occlusion associated with recent onset of occlusion. Factors such as emotional status and associated systemic disease may play a role in predisposition of retinal vascular occlusion, so more-precise studies are needed to determine the possible risk factors of hyperhomocysteinaemia in retinal vascular occlusion.