Is there a way to measure the number of each type of cone (photoreceptors in the back of the eye that help us perceive color) in the fovea to see if someone has a normal amount of each?

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Is there a way to measure the number of each type of cone (photoreceptors in the back of the eye that help us perceive color) in the fovea to see if someone has a normal amount of each?

JUL 19, 2017

Question:

Is there a way to measure the number of each type of cone (photoreceptors in the back of the eye that help us perceive color) in the fovea to see if someone has a normal amount of each?

Answer:

There is no way to count the number of each type of cone photoreceptor. You can find out how well someone’s cones are working with certain types of testing. There are also imaging techniques to evaluate the anatomy of the cones, but these cannot distinguish between the different types of cones.

Answered By: George A Williams, MD

General Eye Health
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Is there a way to measure the number of each type of cone (photoreceptors in the back of the eye that help us perceive color) in the fovea to see if someone has a normal amount of each?

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