How does untreated elevated intraocular pressure eventually lead to visual impairment?
a. It compresses blood vessels and causes hypoxia of the photoreceptors.
b. It clouds the lens and prevents light from striking the photoreceptors.
c. It constricts the pupil and prevents light from entering the posterior chamber.
d. It pushes the cornea forward and distorts the placement of the image on the retina.
A
The photoreceptors of the retina are the part of the sensory nerve that respond to light and enable vision. These receptors require a constant supply of oxygen. Higher than normal intraocular pressure compresses retinal vessels and limits or prevents blood flow to these receptors. As a re-sult of this lack of oxygen, the receptors die and are not replaced. Loss of any photoreceptors reduces vision. Loss of them all causes total blindness.
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