الفهرس 
Anatomy and PhysiologyOnly 14 pages are availabe for public view
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Abstract
Glaucoma, a leading cause of irreversible blindness worldwide, is an optic neuropathy characterized by death of RGCs, associated with specific visual field defects and structural changes at the level of the optic nerve and retinal nerve fiber layer (RNFL). These structural changes, including deep optic nerve structure changes the LC and RNFL damage, gradually progress and become clinically evident as an increased excavation of the optic disc that usually precedes detectable function loss as determined by visual field testing. Primary open-angle glaucoma (POAG) is the most common type of glaucoma and is characterized by increased resistance to aqueous outflow and damage to optic nerve without known ocular or systemic disorders. Elevated intraocular pressure (IOP)is a major and the only modifiable risk factor for POAG. Choroidal thickness (CT) analysis can be done using swept- source optical coherence tomography (OCT). It has been shown that glaucoma patients usually present with peripapillary choroidal thinning, especially in areas further away from the optic disc. It has been also reported that patients with advanced POAG have a thinner subfoveal choroidal thickness as compared with normal populations. RNFL thinning is the hallmark of glaucomatous optic neuropathy and is difficult to detect during clinical examination with fundoscopy or slit-lamp fundus biomicroscopy. With advancement of technology, imaging of the optic nerve head using OCT enables in vivo assessment of retinal layers, providing near histological resolution images. Cross-sectional imaging and measurement of the RNFL using OCT is reliable and shows high accuracy of structural changes of the optic nerve head.