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Retina and Macular Degeneration - explained fast

Retina and Macular Degeneration - explained fast

The rod cells in the retina can detect a single photon. These cells are responsible for peripheral vision and low light vision. They provide black/white/grey vision and cannot detect color.

Special proteins in the cells can absorb an individual photon and as a result change the cell's membrane potential enough to trigger the cell.

The retina contains about 100 million rod cells.

The cone cells in the retina provide color vision. The retina has about 6 million cone cells and almost all are concentrated in a tiny dimple on the retina called the macula. It's only a few mm wide. This minuscule structure gives us our central field vision and our color vision!

Cone cells can detect frequency of light and there are 3 types of cones, each sensitive to a different frequency range. The B cones are most sensitive to blue, the G cones are most sensitive to green and the R cones are most sensitive to red. So our color vision is called "tricolor vision". By comparing outputs from the 3 cell types the brain mixes the 3 color signals to detect any color!

Macular degeneration comes in two types: wet and dry. Dry is not so bad. But wet can lead to rapid vision loss. There are injections for wet macular degeneration. These injections deliver medication directly into the eye to slow down the growth of abnormal blood vessels and prevent fluid leakage that damages the macula. Speak with your doctor about injection options.

Content written and posted by Ken Abbott
Disclaimer: This is for general information purposes only. It is not intended as medical advice.
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