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The inner layer (Retina): The retina of the eye consists of two major parts; 1) the optics and the nonvisual parts. We can break down the optics portion further. It is composed of two layers; a light sensitive neural layer and a pigment layer that helps light absorb by reducing scatter. The non-visual retina
is a continuation of the pigment layer. It extends over the ciliary body and the posterior of surface of the
iris.
Ocular Fundus: The fundus of the eyeball is where the light entering the eye is focused. The retina of
the fundus contains the optic disc or the optic papilla. The optic papilla is the point where sensory fibers
and vessels, carried by the optic nerve, enter the eyeball. Since the optic disk contains these vessels
and no light sensitive cells, this is also called the blind spot. Also, within the retina, lateral to the optic
disc, is the macula Lutea, yellow spot. The macula has specialized cells used for acute vision. It‘s
termed the yellow spot and can also, only be seen when viewing the retina with a red-free light, therefore is not normally seen with the ophthalmoscope. The macula will be in an area without a capillary
network and at its center is a depression, fovea centralis, where the highest visual acuity takes place.
Diseases of the eye: Hypertensive Retinopathy
Lesions:
Flame shaped hemorrhages
Narrow tortuous arteries
Bright spots, cotton wool patches, caused by focal ischemia
Macular Degeneration
Lesions:
Blood vessels arching out from the optic disc toward the
macula
Macula covered in ―drusen‖, (white spots)