Human Vision The Snellen Visual Acuity Chart What

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Human Vision

Human Vision

The Snellen Visual Acuity Chart

The Snellen Visual Acuity Chart

What is Meant by 20/20 vision? At a distance of 20 feet, a normal

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

Ishihara tests for color deficiency • http: //www. toledo-bend. com/colorblind/Ishihara. html

Nearsightedness – “myopia” • Eyeball is abnormally long • Image focuses in front of

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 •

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

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

Cataract • Lens becomes opaque preventing light rays from reaching the retina

Hyphema • Bleeding into the anterior chamber of the eye due to a direct

Hyphema • Bleeding into the anterior chamber of the eye due to a direct blow • May obscure all or part of the iris • May impair vision

Conjuctivitis “Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching,

Conjuctivitis “Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching, yellow discharge • Viral or bacterial

Sty • Infection of the eyelid follicle • Moist heat packs • Do Not

Sty • Infection of the eyelid follicle • Moist heat packs • Do Not pop

Orbital Fractures • Blowout Fracture: A fracture to the eye orbit, particularly its floor.

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

Impaled Object in Eye

Impaled Object in Eye

Injuries to the Face and Spine

Injuries to the Face and Spine

Jaw Fractures

Jaw Fractures

Le. Fort Fractures

Le. Fort Fractures

Orbital Fractures • Blowout Fracture: A fracture to the eye orbit, particularly its floor.

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

Nasal Fractures

Nasal Fractures

Epistaxis • Nosebleed • Direct pressure – 15 min. • DO NOT tilt head

Epistaxis • Nosebleed • Direct pressure – 15 min. • DO NOT tilt head back

Cauliflower Ear (Hematoma Auris) • Bleeding and fluid accumulation between cartilage and skin •

Cauliflower Ear (Hematoma Auris) • Bleeding and fluid accumulation between cartilage and skin • Excessive friction or trauma • Ice, compression, drainage?

Swimmer’s Ear (Otitis Externa) • Infection of the ear canal due to moisture •

Swimmer’s Ear (Otitis Externa) • Infection of the ear canal due to moisture • Drops before swimming (3% boric acid and alcohol)

Sty • Infection of the eyelid follicle • Moist heat packs • Do Not

Sty • Infection of the eyelid follicle • Moist heat packs • Do Not pop

Conjuctivitis “Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching,

Conjuctivitis “Pink Eye” • Inflammation of the conjunctiva of the eye • Burning, itching, yellow discharge • Viral or bacterial

Hyphema • Bleeding into the anterior chamber of the eye due to a direct

Hyphema • Bleeding into the anterior chamber of the eye due to a direct blow • May obscure all or part of the iris • May impair vision

Dental Injuries

Dental Injuries

Impaled Object in Eye

Impaled Object in Eye