Evaluation of radial optic neurotomy for central retinal vein occluion by indocyanine green videoangiography and image analyi

Purpoe To evaluate the effect of radial optic neurotomy (RON) on retinal circulation in patient with central retinal vein occluion (CRVO) by indocyanine green (ICG) videoangiography and a computer-aited image analyi. Deign An interventional cae erie. Method RON wa performed in 15 eye of 15 patient with CRVO. Within 72 hour before the urgery and at 3 month after the urgery, ICG videoangiography wa performed with a canning laer ophthalmocope, and the image were tranferred to a computer. Two meaurement point were elected, one on a main retinal artery cloe to the optic dik and the other on the correponding retinal vein. At each point, fluorecence intenitie were erially meaured, and dye dilution curve were obtained. Retinal circulation time (ΔT50) before and after the urgery were calculated. Reult Mean preoperative ΔT50 wa 6.46 ± 1.36 econd, and mean potoperative ΔT50 wa 6.80 ± 2.50 econd. In 8 of 15 eye, T50 decreaed by 6.8% to 29.6% after the urgery. In the even eye that developed chorioretinal anatomoi (CRA) at the ite of RON, ΔT50 decreaed after the urgery. In contrat, ΔT50 decreaed potoperatively in only one of the eight eye without CRA. Bet-corrected viual acuity improved ignificantly after the urgery in the group of eye with improvement in ΔT50, but not in the group of eye without improvement inΔT50. Concluion ome degree of retinal circulation improvement occurred in approximately half of thee eye, which appear to be correlated with the development of CRA.