Abstract
Purpose :
To investigate longitudinal changes of vessel density (VD) in cases converting from non-ischemic central retinal vein occlusion (N-iCRVO) to ischemic (iCRVO).
Methods :
Optical coherence tomography angiography (OCTA) data of 11 eyes with N-iCRVO who were followed for more than 12 months were retrospectively reviewed. The VD in superficial capillary plexus (SCP) was obtained by OCTA scans of 3×3 mm. We investigated the rate of change (%/year) of VDs by using The Trend Analysis tool in the OCTA firmware (Version 2017.1.0.155, Optovue. Inc.).
Results :
The average follow-up period was 17.1±5.0 months. Two of 11 eyes (18.2%) converted from N-iCRVO to iCRVO. There were no significant difference in age (N-iCRVO:72.2±7.7 vs. iCRVO:81.0±2.8, p=0.17) and the baseline VDs (N-iCRVO:39.8±3.7 vs. iCRVO:37.8±2.1, p=0.41). The rate of change of VDs was significantly higher in those cases converting to iCRVO (-12.9±4.5 %/year) than those maintaining in N-iCRVO(-0.6±2.4 %/year) (p=0.045). The VD of the two eyes converting to iCRVO did not decrease rapidly at a certain visit but decreased gradually over the follow-up period of 22 months or more.
Conclusions :
Drop out of the retinal vessels in eyes converting from N-iCRVO to iCRVO may gradually progress over months. The rate of change of VD in SCP calculated by Trend Analysis tool may predict those prognoses.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.