Hyaloid Canal Research Paper

Hyaloid canal: The hyaloid canal is a small, transparent tunnel that traces its path through the vitreous body of the eye, spanning the optic nerve disc to the lens. In an adult person, the hyaloid canal carries lymph to help change the volume of the lens. When the lens expands, the hyaloid canal compresses, so that the eye’s internal pressure and volume remain constant (Merriam-Webster).
Optic nerve: A part of the central nervous system, the optic nerve connects the eye to the brain, carrying electrical signals formed by the retina to be interpreted as images (Medicine Net).
Central retinal vein: The central retinal vein is where blood circulating in the eye is returned to the heart to be cleaned. It forms the arterioles, branches of an …show more content…
Rays that enter the eye parallelly must be bent into focusing at a point; this is called “refraction,” or bending light rays as they pass from one medium into another of a different density: solid into liquid, or, in the specific case of the eye, air into water. The light that enters and is refracted inside the cornea then passes through the pupil, a round opening at the center of the iris. The amount of light let in is determined by environmental factors and the iris, which acts as an adjustable diaphragm controlling the dilation of the pupil (Health Guidance). In dim lighting, the the iris will expand the pupil, or dilate it, to permit more rays in. If it is bright, however, the pupil will shrink to avoid damage. Once past the pupil, light then hits the eye’s lens. The lens of the eye works very much like the lens of a camera, altering its width to bring the light into focus (NKFC). The lens is crystalline and pliable, casting an upside-down image onto the wall of the retina (Sciencing). The retina, a layer of light-sensitive photoreceptor cells, registers this image with rods and cones. Here, in the retina, the rays are focuses into a point (Glasses Crafter); and here, several things can go wrong while translating light into an image. For example, myopia, or nearsightedness, occurs when light rays are bent too far for the retina to focus on; meanwhile, hyperopia, or farsightedness, occurs when light is not bent far enough. With astigmatism, vision is blurred as the result of an irregularly-shaped eyeball scattering light rays erratically (Glasses Crafter). If all goes according to plan, and the retina picks up the light, a signal will be carried to the brain via the optic nerve. Once the retina senses the image, it sends impulses to the optic nerve at the back of the eye. The brain, upon receiving these signals in the form of electrical impulses,