the central 24 to 30° visual field, so it may not be visible with standard central field measurements done in glaucoma. Field defects in macular degeneration (AMD) The macula of the retina is the central area in the visual field of about 10 to 17 deg diameter (in visual angle). It is responsible for high-resolution vision in good light, in particular for reading. Many diseases affecting the macula may cause defects in the central field of vision, among them Metamorphopsia and central scotomas. Field defects in visual pathway lesions The visual pathway consists of structures that carry visual information from the retina to the brain. Lesions in the pathway cause a variety of visual field defects. The type of field defect can help localize where the lesion is located (see figure). A lesion in the optic nerve of one eye causes partial or complete loss of vision in the same eye, with an intact field of vision in other eye. A lesion at the proximal part of optic nerve of one eye cause, central field defect in one eye and temporal half-field defect in the other eye (not shown in the figure). A lesion in the center of the optic chiasma causes bitemporal hemianopia A lesion to the optic tract, or involving the complete optic radiation causes homonymous hemianopia When part of the optic radiation in the parietal lobe is affected, the resulting field defect may be inferior quadrant hemianopia Neurological Causes of Visual Field defects Cerebral palsy: Field loss due to cerebral palsy may be hemianopic affecting even upper or lower half, central scotoma, peripheral scotoma, or islands of vision. Epilepsy: Although field defects are rarely associated with epilepsy, defects may occur after temporal lobe surgery for epilepsy. Periventricular leukomalacia (PVL): Bilateral inferior visual field defects may occur due to damage of the optic radiations Other causes of field defects Generalized depression is seen in cataract Central visual field loss is seen in Optic neuritis, Leber hereditary optic neuropathy, Macular hole, Cone dystrophy, Branch retinal artery occlusion etc. Peripheral visual field loss including tunnel vision is seen in Retinal detachment, Retinitis pigmentosa, Branch retinal vein occlusion etc. Hemianopia and quadrantanopia are seen in patients with stroke, traumatic brain injury, tumor etc. Altitudinal visual field defect is seen anterior ischemic optic neuropathy, compressive neuropathy (due to a tumor or aneurysm), Branch retinal artery occlusion, Branch retinal vein occlusion, Coloboma, Papilloedema,