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Human Vision. The Snellen Visual Acuity Chart. What is Meant by 20/20 vision?. At a distance of 20 feet, a normal eye can read the 20 foot line. 20/15 = person can see at 20 feet what a person with normal vision can see at 15 feet
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What is Meant by 20/20 vision? At a distance of 20 feet, a normal eye can read the 20 foot line. 20/15 = person can see at 20 feet what a person with normal vision can see at 15 feet 20/100 = person can see at 20 feet what a person with normal vision can see at 100 feet
Ishihara tests for color deficiency • http://www.toledo-bend.com/colorblind/Ishihara.html
Nearsightedness – “myopia” • Eyeball is abnormally long • Image focuses in front of retina • Can see well at short distances, can’t see far
Farsightedness – “hyperopia” • Eyeball is abnormally short • Image focused behind retina • Unable to see close
Astigmatism • Blurred or distorted images due to imperfections in the shape of the cornea or lens
Cataract • Lens becomes opaque preventing light rays from reaching the retina
Bleeding into the anterior chamber of the eye due to a direct blow May obscure all or part of the iris May impair vision Hyphema
Conjuctivitis“Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching, yellow discharge • Viral or bacterial
Infection of the eyelid follicle Moist heat packs Do Not pop Sty
Blowout Fracture: A fracture to the eye orbit, particularly its floor. The fracture may entrap some of the muscles that control eye movements Orbital Fractures
Blowout Fracture: A fracture to the eye orbit, particularly its floor. The fracture may entrap some of the muscles that control eye movements Orbital Fractures
Nosebleed Direct pressure – 15 min. DO NOT tilt head back Epistaxis
Bleeding and fluid accumulation between cartilage and skin Excessive friction or trauma Ice, compression, drainage? Cauliflower Ear (Hematoma Auris)
Infection of the ear canal due to moisture Drops before swimming (3% boric acid and alcohol) Swimmer’s Ear(Otitis Externa)
Infection of the eyelid follicle Moist heat packs Do Not pop Sty
Conjuctivitis“Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching, yellow discharge • Viral or bacterial
Bleeding into the anterior chamber of the eye due to a direct blow May obscure all or part of the iris May impair vision Hyphema