copyright © 2010 delmar, cengage learning. all rights reserved. chapter 16 eye and ear diseases and...
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Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.
Chapter 16
Eye and Ear Diseases and Disorders
Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.
Anatomy and Physiology of the Eye
• Sensory organ located in orbit of skull
• Components:– Sclera, cornea, iris, and pupil
– Anterior and posterior chambers
– Lens, retina, choroid layer, and posterior cavity
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Animation
Click Here to Play Vision Animation
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Anatomy and Physiology of the Ear
• External ear– Pinna and auditory canal
• External and middle ear separated by tympanic membrane
• Middle ear– Also known as tympanic cavity
– Malleus, stapes, and incus bones
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Anatomy and Physiology of the Ear
• Inner ear– Most sophisticated
– Vestibule, semicircular canals, round window, and cochlea• Responsible for hearing and equilibrium
• Cochlea– Organ of hearing
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Animation
Click Here to Play Hearing Animation
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Common Signs and Symptoms of the Eye
• Pain or burning in or around eye
• Decreased visual acuity or ability to see
• Any disorder– E.g., seeing flashes of light
• Eye redness
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Common Signs and Symptoms of the Ear
• Otalgia
• Deafness
• Vertigo
• Tinnitus
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Diagnostic Tests of the Eye
• Ophthalmoscopy
• Visual acuity
• Tonometry
• Slit lamp
• Angiography
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Diagnostic Tests of the Ear
• Otoscopy
• Audiometry
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Refractive Errors of the Eye
• Inability to focus images on retina
• One-third of population affected
• Types:– Myopia
• Nearsightedness
– Hyperopia• Farsightedness
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Refractive Errors of the Eye
• Types:– Presbyopia
• Age-related hyperopia
– Astigmatism• Irregularity of cornea surface
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Inflammation and Infection of the Eye
• Conjunctivitis– Inflammation of conjunctiva
– Excessive tearing, itching, burning, and pain
– Treatment:• Warm compresses
• Anti-inflammatories
• Analgesics
• Perhaps antibiotic ointment
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Inflammation and Infection of the Eye
• Conjunctivitis– Prevention:
• Good hygiene
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Conjunctivitis
Photo courtesy Mark L. Kuss
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Inflammation and Infection of the Eye
• Blepharitis– Inflammation of edge of eyelid, eyelash follicles, and
glands
– Causes:• Bacterial infection
• Allergic reaction
• Seborrhea
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Inflammation and Infection of the Eye
• Blepharitis– Symptoms:
• Red, swollen, and crusted eyelids
– Treatment:• Antibiotics
• Allergy medication
• Treatment of seborrhea
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Inflammation and Infection of the Eye
• Keratitis– Inflammation of cornea caused by trauma or infection
– Usually unilateral
– Symptoms:• Photophobia
• Pain
• Excessive tearing
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Inflammation and Infection of the Eye
• Keratitis– Treatment:
• Antibiotic ointment or drops
• Analgesics
• Eye patch
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Inflammation and Infection of the Eye
• Stye– Also known as hordeolum
– Inflammatory infection of sebaceous gland of eyelid
– Resembles pimple
– Usually caused by staphylococcus bacteria
– Treatment:• Warm compresses
• Topical or systemic antibiotics
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Cataract
• Clouding of lens
• Causes:– Change in metabolism and nutrition in lens
– Aging
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Cataract
• Symptoms:– Decreased visual acuity
• Treatment:– Lens replacement surgery
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Cataract
Photo courtesy Mark L. Kuss
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Glaucoma
• Characterized by excessive eye pressure
• Slow progression with or without symptoms
• Permanent damage can occur before symptomatic
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Glaucoma
• Treatment:– Eye drops
– Surgery
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Nystagmus
• Constant, involuntary movement of eyes
• May affect one or both eyes
• Causes:– Brain tumors
– Disease
– Alcohol abuse
– Congenital defects
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Nystagmus
• Treatment:– Correct underlying cause
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Strabismus
• Eyes fail to focus in same direction simultaneously
• Due to muscle weakness in one or both eyes
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Strabismus
• Treatment:– Cover normal eye to train affected eye to function
– Eye exercises
– Corrective lenses
– Surgery
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Strabismus
Photo courtesy Mark L. Kuss
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Macular Degeneration
• Degeneration of macular area of retina
• Cause:– Most commonly age-related
• Symptoms:– Loss of central vision
• Treatment:– Laser surgery to improve vision
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Diabetic Retinopathy
• Leading cause of blindness in United States
• Diabetes mellitus causes vascular changes in retina leading to decreased visual acuity
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Diabetic Retinopathy
• Treatment:– Laser photocoagulation
• Prevention:– Controlling blood sugar
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Color Blindness
• Also called color vision deficiency (CVD)
• Ability to see color diminishes with age due to yellowing of lens
• Inherited
• Most common affects ability to distinguish between red and green
• No cure
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Infection of the Ear
• Otitis media– Inflammation in middle ear
– Usually affects infants and young children
– Types:• Serous
• Suppurative
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Infection of the Ear
• Otitis media– Treatment:
• Analgesics
• Decongestants
• Antibiotics
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Infection of the Ear
• Otitis externa– Also known as swimmer’s ear
– Inflammation of external ear canal caused by bacterial or fungal infection
– Symptoms:• Extreme pain
• Fever
• Pruritus
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Infection of the Ear
• Otitis externa– Symptoms:
• Hearing loss
• Clear or purulent drainage
– Treatment:• Keep ear canal clean and dry
• Analgesics
• Antibiotics
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Infection of the Ear
• Mastoiditis– Inflammation of mastoid bone or process
– Acute mastoiditis usually result of middle ear infection
– Symptoms:• Tinnitus
• Otalgia
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Infection of the Ear
• Mastoiditis– Treatment:
• Antibiotics
• Mastoidectomy
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Deafness
• Affects more than 25 million people
• Conductive and sensory– Conductive
• Caused by external or middle ear disorders that decrease or stop sound conduction
– E.g., impacted cerumen, otosclerosis, ruptured eardrum
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Deafness
• Conductive and sensory– Sensory
• Cochlear or auditory nerve damage preventing sound to be carried to brain
• Cause related to damaging noise levels and ototoxic medications
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Deafness
• Impacted cerumen– Cerumen
• Soft, yellow-brown secretion
• Also known as earwax
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Deafness
• Impacted cerumen– Causes:
• Skin dryness
• Excessive hair
• Narrow ear canal
• Excessive dust
– Treatment:• Ear irrigation
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Deafness
• Otosclerosis– Bony fixation of middle ear bones do not allow vibrations
from eardrum to inner ear
– Treatment:• Stapedectomy
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Deafness
• Sensorineural deafness– Sensory deafness due to damage to cochlea or auditory
deafness• Damage may be due to exposure to loud noise
• Damage often permanent
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Deafness
• Presbycusis– Progressive sensory deadness related to aging
– Symptoms usually begin after age 50
– Treatment:• Use of hearing aid
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Motion Sickness
• Experiencing nausea when traveling by car, boat, or airplane
• Symptoms:– Nausea and vomiting
– Diaphoresis
– Vertigo
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Motion Sickness
• Treatment:– Anti-motion sickness medication
– Rest
– Closing of eyes
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Trauma
• Corneal abrasion– Causes:
• Obstruction trapped between eyelid and cornea
• Ill-fitting or worn contact lenses
• Accidentally poking finger in eye
• Extreme light– E.g., welding
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Trauma
• Corneal abrasion– Treatment:
• Remove obstruction
• Antibiotic ointment or analgesics
• Pressure dressing to prevent eye movement
• Reduce photophobia pain
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Trauma
• Retinal detachment– Often occurs with trauma, diabetes, and other retinopathies
– Symptoms:• Blurred vision
• Flashes of light
• Floating spots
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Trauma
• Retinal detachment– Painless disorder, but needs attention
– Treatment:• Surgery
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Trauma
• Ruptured tympanic membrane– Causes:
• Middle ear infection
• Sticking sharp object in ear canal
– Symptoms:• Pain
• Partial loss of hearing
• Bloody or purulent discharge
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Trauma
• Ruptured tympanic membrane– Treatment:
• Antibiotics
• Surgical patching of membrane with tissue graft
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Rare Diseases
• Retinoblastoma– Hereditary malignant tumor of eye occurring during
infancy and childhood
– Fatal if untreated
– Treatment:• Enucleation
• Radiation
• Chemotherapy
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Rare Diseases
• Meniérè’s disease– Chronic disease of inner ear
– Symptoms:• Tinnitus
• Vertigo
• Progressive hearing loss
• Feeling of fullness in ear
– Attacks last few hours to several days
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Rare Diseases
• Meniérè’s disease– Treatment:
• Medications to control nausea
• Low-salt diet
• Diuretics
• Antihistamines
• Smoking cessation
– Surgery may be necessary
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Effects of Aging on the Eye
• Changes in ability to focus on near objects, color perception, some sensitivity to light, and decreased visual acuity
• Glaucoma and cataracts
• Arcus senilis
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Arcus Senilis
Photo courtesy Mark L. Kuss