Contributory factors for developing foveal neovascularization in proliferative diabetic retinopathy

Purpose Foveal neovascularisation (NV) in proliferative diabetic retinopathy (PDR) is uncommon. The study aim is to analyse a series of cases of foveal NV in PDR and ascertain the factors leading to its development. Methods In this retrospective case-control study, optical coherence tomography (OCT) and OCT-angiography (OCTA) images of PDR cases with/without foveal NV diagnosed on fluorescein angiography were analysed. Results From 124 consecutive PDR eyes, foveal NV was identified in 12 (10%) eyes. Eyes with foveal NV showed thin choroid (p = 0.001), increased FAZ area and reduced vessel density at the macula compared to control group on OCT and OCTA. After regression analysis, an increased FAZ in the superficial capillary plexus slab (p = 0.002) was associated with foveal NV development. Conclusion Our case series suggest that foveal NV is an uncommon finding, occurring due to reduced choroidal and inner retinal perfusion at the macula. Further studies are required to assess the treatment outcomes in such eyes.