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ree-FRAK-tiv SUR-jah-ree
See PRK, LASIK & RK.
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A thin tissue lining the innermost wall of the eye. Once light has passed through the iris, it hits the retina and is converted to electrical signals which are carried by the optic nerve to the brain. The outlying parts of the retina are responsible for peripheral vision while the center area, called the macula, is used for fine central vision and color vision.
REH-tih-nah)
A thin tissue lining the innermost wall of the eye. Once light has passed through the iris, it hits the retina and is converted to electrical signals which are carried by the optic nerve to the brain. The outlying parts of the retina are responsible for peripheral vision while the center area, called the macula, is used for fine central vision and color vision.
When a portion of the retina comes loose from the back of the eye, the separation is called retinal detachment. Peripheral vision is usually lost first, and if the detachment continues, all vision in that eye may be completely lost.
Example of vision with retinal detachment:
In a vitreous detachment, the vitreous pulls away from the retina, causing the patient to see flashes of light.
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A malignant tumor of the retina that appears in early life and may occur in one or both eyes. Usually observed before the age of 5, it is composed of embryonic cells and tends to invade the choroid and optic nerve. In some cases, it may extend beyond the confines of the eyeball and cause cataracts and glaucoma.