But it does not harm the optic nerve, which transmits electrical impulses from the retina to the brain.
These light receptors - which are also found in the retina of the eye - immediately prompt the release of melanin, the body's own form of sun protection.
These alter the activity of three genes that control the growth of the eyeball and ensure light entering the eye is converted into electrical pulses in the retina.
When you are short-sighted, your eyes focus well only on close objects, while more distant objects appear blurred. This is because light rays focus in front of the retina.
The device then magnifies and projects the images onto a healthy portion of the retina.
trauma cases with retina detachment have been measured(media cloud and can not see the fundus)by using 2 dimensional ultrasound and color Doppler for 2 demision structure and blood flow imaging on the branch retina artery.
"Continuing Blindness may arise from injuries or diseases of the eye (e.g., cataract, glaucoma),including the retina, the optic nerve, or the Brain's visual centres."
After the procedure, your cornea should bend (refract) light rays to focus more precisely on your retina rather than at some point beyond or short of your retina.
As early as 1962 a ruby laser welded a detached retina to a patient's eyeball to save their vision.
Signals from the retina flow to the most basic processing area first; the cells in that area fire up others in the next area; and so on.
Disorders affecting the retina or the macula in its centre decrease vision and can cause Blindness.
The macula is an area on the retina that provides a clear, sharp image to our central vision.
The pressure causes tiny blood vessels in the retina to kink and twist, which is pointed out by one other arrow points to "dents" in retinal veins, a condition known as A-V nicking.
If a cataract blocks light from entering the eye and stimulating the retina, the area of the brain used for sight does not develop properly.
Researchers believe they may be able to replace damaged cells in the retina with similar ones found in algae.
The optical system of the eye stimulate cell of the retina.
Once the retina detaches it assumes a slight opaque color with a convex configuration and a corrugated appearance (arrow).
The light sensitive receivers are found on the retina and can be likened to the pixels of a digital camera chip and are separated out into two sorts: rods and cones.
Each sensor has its own microelectrode, and these are placed in contact with nerve cells in the retina, called bipolar cells, the first step on the pathway from the eye to the brain.
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