Diabetic retinopathy represents the most common cause of vision loss in working aged adults. Vision loss is related to two manifestations of advanced diabetic retinopathy: proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME). PDR occurs when the vascular perfusion of the retina is compromised and compensatory signals including expression of vascular endothelial growth factor causes neovascularization on the surface of the retina. These abnormal vessels cause vision loss by either bleeding into the vitreous or by contracting leading to retinal detachment. DME occurs when vascular leakage results in swelling of the macular tissue causing central vision loss. While DME affects the macula (the area typically imaged using OCT), PDR is much more frequently found in the peripheral retina which is not typically imaged by traditional OCT devices. In recently years, wide field fluorescein angiography has allowed insights into the relationship between DME, PDR and the status of retinal blood vessels within the macula and the retinal periphery. WF-AO-OCT has the potential to provide similar or complementary structural detail of the retinal tissue and vasculature within the macula and retinal periphery. The advantage of WF-AO-OCT is that it is a non-contact, non-invasive imaging technology which is easier to use, faster and less invasive compared to fluorescein angiography which entails intravenous injection of fluorescein, requires a skilled ophthalmic photographer and takes 10-20 minutes to perform. By imaging participants who have previously undergone wide field fluorescein angiography as standard of care, the investigators will be able to compare the information obtained using WF-AO-OCT and to determine its sensitivity in identifying specific vascular and morphological findings associated with PDR and DME.