Updated June 19, 2014.

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Definition:

A scotoma is a localized area of decreased or missing vision within the visual field. Commonly known as a blind spot, a scotoma is the location on the retina where the optic nerve exits the back of the eye.

Because there are no photoreceptor cells (rods and cones) at this point on the retina, there is a very small gap in the visual field.

A scotoma is present in the fields of vision of all normal eyes.

Also Known As: Blind spot