Macular Hemodynamics before and after Retinal Photocoagulation in Branch Retinal Vein Occlusion using Heidelberg Retina Flow meter(HRF )

ABSTRACT

To investigate the pathogenesis of macular edema in branch retinal vein occlusion(BRVO)and its attributing factors, we measured the macular circulation using HRF(Heidelberg Retina Flowmeter)before, 1 hour, 1 day, and 1 month after grid laser photocoagulation in 12 patients. After laser photocoagulation, the macula circulation significantly increased in 8 eyes(group 1), and remained unchanged in 4 eyes(group 2). Mean postoperative macular circulation of group 1 was blood volume 136.2%, blood flow 148.0%, and blood velocity 144.4%. And mean postoperative macular circulation of group 2 was blood volume 103.8%, blood flow 97.8%, and blood velocity 98.8%. The mean age of the patient was higher in group 1(group1mean age 59.0, group 2mean age 43.5, p=0.0008)and the interval between the onset of BRVO and photocoagulation was longer in group 1 than in group 2(group 112.4 months, group 24.3 months, p=0.0233). Our results suggest that retinal autoregulation may play an important role in the resolution of macular edema in BRVO after grid photocoagulation. Therefore the evaluation of retinal autoregulation using HRF is important in determining the treatment guide line and the prognosis of photocoagulation.