Late complications in branch retinal vein occlusion.

Neovascularization in branch retinal vein occlusion usually develops 6-12 months after the onset of the disease, although some cases have been reported in which neovascularization and subsequent vitreous haemorrhage developed 2-3 years later. This is a report of nine cases of late appearance of vitreous haemorrhage due to branch retinal vein occlusion, which occurred 3-6 years after the initial onset of the disease. In two of these nine cases the vitreous haemorrhage was very profound and had to be managed by vitrectomy.