Longitudinal neovascular changes on optical coherence tomography angiography in proliferative diabetic retinopathy treated with panretinal photocoagulation alone versus with intravitreal conbercept plus panretinal photocoagulation: a pilot study

Abstract

Purpose To investigate the longitudinal changes in neovascularization of the retinal elsewhere (NVE) size on optical coherence tomography angiography (OCTA) in proliferative diabetic retinopathy (PDR) treated by panretinal photocoagulation (PRP) alone or by single intravitreal conbercept injection plus PRP. Methods A prospective pilot study. Forty-four PDR eyes with NVE confirmed by fundus fluorescein angiography (FFA) and OCTA were included. They were assigned to receive PRP alone (PRP group) or intravitreal conbercept injection plus PRP (combination group). Ophthalmic examinations, including BCVA and OCTA to measure the NVE size, were performed at baseline before each PRP session, and at 1, 3, and 6 months. Results Twenty-nine eyes were included in the PRP group, and 15 eyes were included in the combination group. There was no significant difference between the two groups with respect to age, BCVA, and NVE area at baseline. In both groups, there was a significant (P < 0.05) NVE size reduction during the majority of study visits, with the reduction observed in the combination group significantly larger than that in the PRP group. No significant BCVA changes were observed in either groups, except that in the PRP group, the BCVA at 3 months was significantly improved (P < 0.05). No deaths or unexpected adverse events (AEs) were reported. Conclusions Intravitreal conbercept plus PRP was more effective than PRP monotherapy in NVE regression. Precise quantification of the NVE area by OCTA makes it a useful tool for monitoring the response of retinal neovascular lesions to the therapy.

Characterizing Flow and Structure of Diabetic Retinal Neovascularization after Intravitreal Anti-VEGF Using Optical Coherence Tomography Angiography: A Pilot Study

“…Ishibazawa et al have described a rapid regression of flow density after anti-VEGF injection over the optic disc head with recurrence after eight weeks in neovascularization of the disc [14]. He and Yu have described the regression of NV size after PRP and combined anti-VEGF and PRP with similar results to our study [33]. However, the magnitude and sustainability of this flow reduction and what factors may lead to recurrence are still unknown.…”

Update on Optical Coherence Tomography and Optical Coherence Tomography Angiography Imaging in Proliferative Diabetic Retinopathy

“…Namely, with OCT, it is possible to visualize the retinal layers in detail and to distinguish between NVC and IRMAs, and there is less obscuration than FA when there is associated fibrosis and hemorrhaging [6,41,42,79,83,103,104]. In both NVE and NVD, the OCTA flow signals found within the hyperreflective material indicate disease activity and correlate with the OCTA en face image [6,67,72,79]. OCTA is particularly useful and superior to OCT in monitoring treatment response, being able to pinpoint regression, reactivation and resistance to treatment [6,41,79].…”

“…NVEs can develop at different levels of the inner retina, penetrate the ILM and can assume different morphologic patterns in relation to the retina (Figures 3 and 4) [21][22][23]25,27,47,48]. Using OCTA, NVEs can be observed as irregular vessels with a positive flow signal above the ILM, which distinguishes them from other vascular lesions such as IRMA and microaneurysms (Figures 3 and 4) [6,15,26,[36][37][38][39][40][41][42][43][44][45]50,52,54,56,[62][63][64][68][69][70][71][72][73][74][75].…”

Management of Acute Proliferative Diabetic Retinopathy Related Complications During the First COVID-19 Wave

“…A meta-analysis by Gao et al demonstrated fewer PDR complications with the use of anti-VEGF when compared to PRP alone 23 . Through the use of OCTA (optical coherence tomography angiography), He et al suggested that combination PRP plus anti-VEGF treatment was more effective at regressing NVE than PRP alone 24 . If combination treatment were to be offered in routine practise one must consider the practicality in an era of COVID risk mitigation measures for example, cost, availability of resources and multiple hospital visits.…”