الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Fluorescein angiography has been an essential tool in the diagnosis and management of retinal diseases, it gives an idea about the presence, activity, and severity of disease not appreciable through clinical examination alone. The imaging of the fundus had been evolved so rapidly through recent years, firstly traditional fundus cameras up to the most recent UWFA cameras. Traditional fundus cameras offered a field of view ranging from 300 to 60o in one exposure. There are mydriatic and nonmydriatic fundus cameras. The retinal periphery can be viewed with typical fundus cameras if there is excellent pupillary dilation and patient cooperation during the photography. The patient moves the eye in specified directions to image the desired peripheral retinal areas. Several photographs, having been taken with a traditional fundus camera using a lens with a small field of view, can be combined to create a montage that covers large portions of the peripheral retina; such as The seven standard fields (7SF) imaging involved capturing seven photos in a montage comprising 75o of the retina. As imaging of the fundus periphery is now very important in the diagnosis and management of retinal disorders wide angle and UWFA had been developed. Some of them use contact lense such as Pomerantzeff system that provided a 148° field of view, The Panoret-1000 that provided a 100-degree view using a non-mydriatic contact lens and trans-scleral illumination, Staurenghi lens system which uses a multielement contact lens--based system, this lens system is capable of increasing the field of view 5-fold and up to 150 degrees and the Retcam which provides a 130° field of view. Heidelberg uses a confocal scanning laser system, a noncontact ultra-widefield angiography and can provide high quality digital images. Optos was the first commercially available fundus camera that provide the ability to capture 200 degree of the fundus, which equates to about 82.5 percent of the total retinal surface area. It is based on the uses of a confocal scanning laser ophthalmoscope to create images of the retinal periphery with a single capture, without the need for a contact lens or pupillary dilation. A comparison of UWFA with the Optos system versus the Heidelberg noncontact system demonstrated that the Optos captured a significant wider total retinal area, especially nasally and temporally. The Heidelberg system imaged slightly more area superiorly and inferiorly, but both provide UWFA and the difference between them is insignificant. UWFA now become a very important tool in imaging of the retinal periphery which make it superior to conventional imaging as it can capture almost the entire posterior pole in a single picture which allows simultaneous comparison of the macula with the peripheral retina during each angiographic phase. UWFA has demonstrated great utility in the diagnosis and management of a range of retinal conditions including: diabetic retinopathy, vein occlusion, uveitis, sickle cell retinopathy and pediatric retinal disease. UWFA can be used in screening, diagnosis and management of diabetic retinopathy. UWFA can visualizes 3.2 times more retinal surface area than the conventional seven standard fields.43 Wide-field angiography facilitates treatment of proliferative diabetic retinopathy with targeted laser photo- coagulation. UWFA in RVO is able to visualize peripheral nonperfusion or perivascular leakage that would have been missed with traditional imaging. It is a powerful tool to identify therapeutic target areas for photocoagulation. UWFA aids in the early detection and localization of uveitis as well as providing a means for evaluating disease response during management. In pediatrics the Retcam is the commenst fundus camera used as it can be portable and can be applied to neonates, also Optos can be used. FA can be done with oral flourecien which can decrease the disadvantages of intravenous injection. It is used in screening and mangment of ROP with less cardiorespiratory stress, other pediatric retinal diseases that affect the periphery, specifically familial exudative vitreoretinopathy, incontinentia pigmenti, and Coats disease. As any technique UWFA has some limitation which can be summarized as distortion and decreased resolution of peripheral imaging, artifact is produced by eyelashes, the native lens, intraocular lens implants, pigment in the anterior segment, and vitreous opacities. As UWFA has expanded the ability to angiographically evaluate the far periphery of the retina, it can identify abnormality more frequently and earlier than previously. This in turn changes the conception of the disease processes and how best to diagnosis, follow, and treat them. Now the challenge is how to apply the findings on UWFA toward clinical practice.