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Impairments to Vision

Normal vision

Normal Vision

Diabetic Retinopathy

Diabetic Retinopathy

Age-related Macular Degeneration

Age-related Macular Degeneration

In this and all subsequent pictures, fixate on the nose to simulate the vision loss. In diabetic retinopathy, the blood vessels in the back of the eye (retina) may rupture and leak. This causes parts of the retina to die and results in a loss of vision where the leaking occurred. In age-related macular degeneration, the center part of the eye and retina known as the macula dies-off, leaving a black hole or "scotoma" right where you're looking.
Glaucoma and Retinitis Pigmentosa

Glaucoma and Retinitis Pigmentosa

Ring or Donut Scotoma.

Ring or Donut Scotoma

Left Field Homonymous Hemianopia

Left Field Homonymous Hemianopia

Although very different diseases, both glaucoma and retinitis pigmentosa (RP) cause a loss of side vision, leading to "tunnel vision". Often a patient will become legally blind because of the severe loss of side vision. A ring or donut shaped scotoma is an area of reduced vision that forms a shape similar to a ring or donut - the patient can see fine in the center and off-center a little bit but then there is an area of reduced vision followed by another area or normal vision. A left (or right) homonymous hemianopia (also called hemianopsia) means that the patient cannot see anything in the entire left or right visual field in both eyes.

Link to Non-Government site Simulations based on Ohio LIONS Eye Research Foundation (OLERF) images



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