Light perception in diabetic vitreous haemorrhage and its prognostic value in pars plana vitrectomy.

Ninety-two years with a pre-operative visual function of light perception 6 m or less, were treated with vitrectomy because of diabetic vitreous haemorrhage. The post-operative visual function after 6 months was improved to 5/50-5/5 in 37 eyes and counting fingers from 1 to 5 m in 32 eyes. In 23 eyes the postoperative visual function was unchanged or decreased, and among these were all 7 eyes with pre-operative light perception at 1.5 m or less. No eye with pre-operative light perception at 1.5 or less benefitted from vitrectomy due to extensive retinal damage.