In Reply The summary by Tan and colleagues that the extent of capillary nonperfusion may not be static in ischemic CRVO complements the findings of our study.1
Tan and colleagues pointed out that some studies have reported decreases in areas of nonperfusion in some patients with retinal vein occlusion.2,3 We agree that the study by Campochiaro et al2 mentioned that reperfusion of areas of RNP occurred at a 6- to 8-fold higher rate (6% or 8%) in patients treated with anti-VEGF drugs compared with patients who received sham treatment (1%), which is consistent with our finding that reperfusion of ischemic areas can occur in patients with CRVO after treatment. However, there seem to be slight differences of opinion. The difference between our study and the study by Campochiaro and colleagues is an area of reperfusion; we found reperfusion of large ischemic areas in severe ischemic cases of CRVO, while very few patients with the ischemic type of CRVO were included in their study. The number of patients with more than 5 or 10 DAs of RNP (0-3 patients) did not change significantly over 12 months in their study. Furthermore, most patients with CRVO (about 80%) had no baseline RNP and 12.3% had between 0 and 1 DA of RNP. Therefore, in their study, if reperfusion developed, it was limited to a very small area (perhaps <1 DA).
Kamei M, Nishida K. Reperfusion of Areas of Ischemia in Central Retinal Vein Occlusion—Reply. JAMA Ophthalmol. 2015;133(2):228-229. doi:10.1001/jamaophthalmol.2014.4249