Small central area of the retina. Vital for sharp central vision.
M (Macula to Meibomian Gland)
Yellow spot. Dense area of cones containing the fovea.
Cancer of the cells responsible for skin pigmentation. Can afflict all skin colours but more common in fair skinned people and tends to be hereditary. Over exposure to the sun heightens the risks. Early diagnosis is essential.
Small glands found in the eyelids responsible for lubrication.
Also Chalazion. Inflammation of the meibomian gland. Can result in a cyst similar in appearance to a pimple.
The black pigment found in the epithelium cells. They prevent light from being reflected back by the retina by absorbing that which has not been captured or utilised by the retina.
Instrument used in refractive surgery to cut the corneal flap in order to expose the inner corneal layers for the laser to sculpt the new curvature. First procedure shown in the video on this site of the operation.
Normal pupil constriction in response to bright light or when focusing on a near object. Speed and amount of closure is dependant on the change in intensity of the light. Can also be induced by certain drugs.
Loss of the protective myelin sheath surrounding nerve tissue causing a chronic disorder of the central nervous system. Can cause double vision involuntary eye movements and reduced vision if there is inflammation of the optic nerve.
Pupil dilation. Increase in the size of the pupil caused normally by a reducion in the intensity of light or by certain drugs. May be induced artificially during certain aspects of a sight test to view more of the inside of the eye.
Drops used to dilate the pupil.
Person who suffers from myopia.
Shortsightedness. Ability to see near objects but not those in the distance. The eye is too long for its focal power resulting in the rays of light focusing infront of the retina caused either by the eyeball being too long or the corneal curvature being too steep or a combination of both.