... stage of mild nonproliferative diabetic retinopathy, opening real opportunitiesfor effective intervention. Four main alterations characterize the early stages of diabeticretinopathy: microaneurysms/hemorrhages, alteration in the blood-retinal barrier, capillaryclosure, and alterations in the neuronal...

... studies and from clinical experience, that the evolution and progression of retinal diseases such as diabetic retinopathy vary between different individuals and does not necessarily progress in every patient to the terminal stage of proliferative retinopathy [ 1 , 2 ]. Microaneurysm formation...

... microaneurysms, non-perfusion, neovascularization, and capillary dilation. Several studies quantifying non-perfusion metrics in DR have demonstrated significant correlation between levels of retinopathy with these metrics. Segmentation schema, projection artifacts, image resolution, and signal strength remain...

... include microaneurysm formation and intraretinal hemorrhage. At present, ophthalmoscopy and color fundus photography are still the gold standard for the diagnosis and staging of DR. However, the presence of microvascular damage is known to occur before findings of retinopathy become apparent on clinical...

..., and vitreous hemorrhages were described in 1876 by Wilhelm Manz, and a year later Mackenzie described microaneurysms together with retinal and vitreous bleeding. Finally, a full histopathological description was published in 1944 by Ballantyne and Lowenstein, who first coined the term “diabetic retinopathy...

.... Microaneurysms and haemorrhages temporal from the fovea (arrows). Fig. 1. Microaneurysms and haemorrhages temporal from the fovea (arrows). In this chapter, the clinical manifestations of diabetic retinopathy will be described, and the background and development of each individual lesion type...

... vascular abnormalities. On FA, microaneurysms appear as pinpoint, hyperfluorescent lesions that become clearer during the course of the examination, while patchy areas of hypofluorescence can correspond to ischemia from nonperfused retinal capillaries. An enlargement of the foveal avascular zone due...

..., and microaneurysm turnover), retinal neurodegeneration (thinning of the retinal nerve fiber layer and ganglion cell layer + inner plexiform layers), and retinal edema (increased thickness of the inner nuclear and outer plexiform layers of the retina) show a wide range of values between different eyes in each...

.... Beyond DME and macular ischemia, OCT permits the individuation of many other lesions occurring in the setting of both non-proliferative (i.e., hyperreflective spots, micropseudocysts, hard exudates, microaneurysm, cotton-wool spots) and proliferative (i.e., neovascularization, vitreoschisis, tractional...

... pattern of hard exudates around the microaneurysms. Fig. 1. CSME. Hard exudates within 500 µm of the macular center and retinal thickening at this area. Note the circinate pattern of hard exudates around the microaneurysms. Epidemiology The incidence of DME has been studied in the Wisconsin...

... by microaneurysms and intraretinal hemorrhages. Progression of diabetic retinopathy is driven by the development of retinal capillary nonperfusion and subsequent retinal ischemia and hypoxia which results in further retinal vascular changes such as venous abnormalities, intraretinal microvascular anomalies...

...-lived species, microaneurysms and intra-retinal microvascular abnormalities. To date, none of these diabetic animal models has been found to reliably develop preretinal neovascularization (an advanced stage of the retinopathy), likely due in part to less vaso-obliteration occurring during the short...

... changes, such as microaneurysms, capillary non- perfusion, and ischemia within the retina, ultimately lead to neovascularization and/or ME, both of which can severely compromise the visual function. Imaging Techniques Fluorescein angiography (FA), the imaging method of choice (“Gold standard...

..., Archer DB: Histological and ultrastructural investigation of retinal microaneurysm development in diabetic patients. Br J Ophthalmol 1995;70:362-367 6. de Venecia G, Davis M, Engerman R: Clinicopathological correlations in diabetic retinopathy I. Histology and fluorescein angiography...

... 2005; 11:1727-1983 3. Nunes S Pires I Rosa A Duarte L Bernardes R Cunha-Vaz J: Microaneurysm turnover is a biomarker for diabetic retinopathy progression to clinically significant macular edema: findings for type 2 diabetics with nonproliferative retinopathy. Ophthalmologica 2009;223:292-297...

... of the retinal and choroidal morphology. OCT-A is a new revolutionary method for the visualization of retinal and choroidal vasculature network that has rapidly reached a key role in the management of DR. OCT-A allows the evaluation of several alterations commonly present in DR, such as microaneurysms, DME...

... in several studies [ 2 – 4 ]. DME. a Early phase fluorescein angiography showing microa-neurysms. b Late-phase fluorescein angiography showing leakage from microaneurysms and accumulation within small cysts superiorly. Fig. 1. DME. a Early phase fluorescein angiography...