الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 113 |  |  |
| | | from | 113 | | |
Abstract
Diabetic retinopathy is a microangiopathy characterized by capillary occlusion, hyperpermeability, and neovascularization. These pathophysiologic changes cause proliferative diabetic retinopathy and macular edema, which are responsible for most of the vision loss associated with this disease
Diabetic macular edema (DME) has become the most frequent cause of vison loss in developed countries. Diabetic macular ischemia (DMI) is also a leading cause of severe visual impairment in diabetic patients. It is also one of the leading causes of preventable blindness in the world, as stated by the WHO.
Early detection and management of DME are essential for the prevention of the detrimental effect it has on vision. Assessment of the microvascular changes with FA has been validated as a way to classify disease severity and predict progression. Like FA, OCT angiography can visualize areas of low capillary perfusion or dropout.
Fluorescein angiography is not relevant in aiding in the diagnosis of CSME but should be performed if treatment of CSME is being considered as it distinguishes and localizes areas of focal versus diffuse leakage, thereby guiding the placement of laser photocoagulation. The proximity of the leakage to the foveal avascular zone should be noted, as well as the presence or absence of ischemic maculopathy.
Angio-OCT or OCT- angiography is a new method of analysis based on high-resolution imaging techniques whereby the retinal and choroidal circulation can be visualized without need to inject of any contrast agent.
This new technology is therefore non-invasive, unlike fluorescein angiography that is currently still considered to be the gold standard of retinal vascular imaging.
OCT-angiography does not show all the microaneurysms, those that are clearly seen are generally the larger microaneurysms where there is probably residual blood flow. The macular ischemia examined by angio-OCT is much sharper than as with fluorescein angiography because there is no masking effect by dye leakage. There are some details in the angio-OCT make it possible to distinguish the recent ischemic areas from consolidated and chronic ischemic areas.
In summary, OCT-A may provide images with greater detail regarding macular status and may become a crucial imaging technique for diagnosis of diabetic macular ischemia in conjunction with fluorescein angiography in the management of diabetic maculopathy.