Early Sign of Retinal Neovascularization Evolution in Diabetic Retinopathy
K. Tsuboi, Mehdi Mazloumi, Yukun Guo, Jie Wang, Christina J. Flaxel, Steven T. Bailey, David J. Wilson, David Huang, Yali Jia, Thomas S. Hwang
Abstract
PurposeTo assess whether the combination of en face OCT and OCT angiography (OCTA) can capture observable, but subtle structural changes that precede clinically evident retinal neovascularization (RNV) in eyes with diabetic retinopathy (DR).DesignRetrospective, longitudinal study.ParticipantsPatients with DR had at least two visits.MethodWe obtained wide-field OCTA scans of one eye from each participant and generated en face OCT, en face OCTA, and cross-sectional OCTA. We identified eyes with RNV sprouts, defined as epiretinal hyperreflective materials on en face OCT with flow signals breaching of the internal limiting membrane on the cross-sectional OCTA without recognizable RNV on en face OCTA; and RNV fronds, defined as recognizable abnormal vascular structures on the en face OCTA. We examined the corresponding location from follow-up or previous visits for the presence or progression of the RNV.Main outcome measureThe characteristics and longitudinal observation of early signs of RNV.ResultsFrom 71 eyes, we identified RNV in 20 eyes with the combination of OCT and OCTA, of which 13 (65%) were photographically graded as PDR, 6 (30%) severe NPDR, and 1 (5%) moderate NPDR. From these eyes, we identified 38 RNV sprouts and 26 RNV fronds at the baseline. Thirty-four RNV (53%) originated from veins, 24 (38%) were from intraretinal micro abnormalities, and 6 (9%) were from a non-dilated capillary bed. At the final visit, 53 RNV sprouts and 30 RNV fronds were detected. Ten eyes (50%) showed progression, defined as having a new RNV lesion or the development of an RNV frond from an RNV sprout. Four (11%) RNV sprouts developed into RNV fronds with a mean interval of 7.0 months. Nineteen new RNV sprouts developed during the follow-up, while no new RNV frond was observed outside an identified RNV sprout. The eyes with progression were of younger age (P = 0.014) and tended to be treatment naïve (P = 0.070) compared to eyes without progression.ConclusionLongitudinal observation demonstrated that a combination of en face OCT and cross-sectional OCTA can identify an earlier form of RNV before it can be recognized on en face OCTA. To assess whether the combination of en face OCT and OCT angiography (OCTA) can capture observable, but subtle structural changes that precede clinically evident retinal neovascularization (RNV) in eyes with diabetic retinopathy (DR). Retrospective, longitudinal study. Patients with DR had at least two visits. We obtained wide-field OCTA scans of one eye from each participant and generated en face OCT, en face OCTA, and cross-sectional OCTA. We identified eyes with RNV sprouts, defined as epiretinal hyperreflective materials on en face OCT with flow signals breaching of the internal limiting membrane on the cross-sectional OCTA without recognizable RNV on en face OCTA; and RNV fronds, defined as recognizable abnormal vascular structures on the en face OCTA. We examined the corresponding location from follow-up or previous visits for the presence or progression of the RNV. The characteristics and longitudinal observation of early signs of RNV. From 71 eyes, we identified RNV in 20 eyes with the combination of OCT and OCTA, of which 13 (65%) were photographically graded as PDR, 6 (30%) severe NPDR, and 1 (5%) moderate NPDR. From these eyes, we identified 38 RNV sprouts and 26 RNV fronds at the baseline. Thirty-four RNV (53%) originated from veins, 24 (38%) were from intraretinal micro abnormalities, and 6 (9%) were from a non-dilated capillary bed. At the final visit, 53 RNV sprouts and 30 RNV fronds were detected. Ten eyes (50%) showed progression, defined as having a new RNV lesion or the development of an RNV frond from an RNV sprout. Four (11%) RNV sprouts developed into RNV fronds with a mean interval of 7.0 months. Nineteen new RNV sprouts developed during the follow-up, while no new RNV frond was observed outside an identified RNV sprout. The eyes with progression were of younger age (P = 0.014) and tended to be treatment naïve (P = 0.070) compared to eyes without progression. ConclusionLongitudinal observation demonstrated that a combination of en face OCT and cross-sectional OCTA can identify an earlier form of RNV before it can be recognized on en face OCTA.