Rods and Cones

Rods and Cones

Rods and Cones

The two types of light-sensitive cells of the retina are rods and cones. Named because of their cylindrical shape, rods are interspersed throughout the retina. They are highly sensitive to low light and shadow and allow for at least some degree of nighttime vision. Cones are present throughout the retina also, but are very highly concentrated in the fovea of the macula. Different cones are sensitive to different wavelengths and allow one to see vivid colors and sharp detail in conditions of bright light. There are 20 times more rods than cones.

Add Image

Retinitis Pigmentosa

Retinitis pigmentosa is one in a group of diseases classified as hereditary chorioretinal dystrophies. There are multiple forms of retinitis pigmentosa, each occurring as a result of a specific abnormal gene. The disease is inherited in a number of different ways. Genetic testing and counseling are very helpful in determining the form of the disease, how it has been inherited, and what treatments are available or are being researched. Retinitis pigmentosa is usually diagnosed during young adulthood and can be difficult to accept.

Syndicate content