Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Essentials of Human Diseases and Conditions 4th edition Margaret Schell Frazier Jeanette Wist Drzymkowski Chapter 5 Diseases and Disorders of the Eye and Ear Learning Objectives Describe the processes of vision and hearing. Recall and define the four main refractive errors of vision. Compare the pathology and etiology of nystagmus and that of strabismus. Explain the importance of early treatment of glaucoma. Name the possible causes of conjunctivitis. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Learning Objectives (cont’d.) List the causes of cataracts. Explain the susceptibility of diabetics to diabetic retinopathy. Characterize the visual disturbance caused by macular degeneration. Explain why early diagnosis and treatment is important in retinal detachment. Compare conductive hearing loss with sensorineural hearing loss. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Learning Objectives (cont’d.) List the symptoms of otitis externa. Describe the treatment of otitis media. Explain the signs and symptoms of Ménière Disease. Discuss the importance of preventing sensorineural hearing loss. Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Chapter 5 Lesson 5.1 Functioning Organs of Vision Vision requires: light stimulus relay of light/image to the retina stimulation of rods and cones in the retina nerve impulses conducted to brain Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Normal Eye Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Functioning Organs of Vision (cont’d.) Signs and symptoms that need medical attention: visual disturbances unequal pupils or sudden loss of vision persistent pain itching or burning in or around the eyes Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Functioning Organs of Vision (cont’d.) Signs and symptoms that need medical attention swollen, red eyelids redness of the eyes drainage or exudate lesions/sores involuntary eye movements Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Eye Refractive Errors Hyperopia (Farsightedness) light focused behind the retina, which impairs near vision Myopia (Nearsightedness) light focused in front of the retina, which impairs far vision Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Eye Refractive Errors Astigmatism • light focused unevenly onto the retina, which causes blurred areas Presbyopia • eye cannot focus quickly to accommodate changes in distance Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Eye (cont’d.) Nystagmus involuntary, repetitive, rhythmic movements of one or both eyes Strabismus failure of the eyes to look together in the same direction Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Eyelid Eye lid disorders caused by inflammation, infection, or other condition include: Hordeolum (stye) Chalazion (stye) Blepharitis Entropion Ectropion Blepharoptosis Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Eyelid (cont’d.) Conjunctivitis inflammation of the conjunctiva in one or both eyes Mucous discharge from the eye can be caused by viral or bacterial infection highly contagious commonly called “pink eye” Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye Cataracts cloudy area in the lens opacity blocks light from reaching retina usually develop slowly gradual reduction of vision Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Glaucoma damage to the optic nerve caused by elevated intraocular pressure open-angle vs. closed-angle One of the major cause of blindness more common after age 60, but can occur at any age more common with nearsightedness Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Macular Degeneration progressive deterioration in retina may start with mild distortion of central vision and progress to complete loss usually both eyes are affected leads to central vision blindness Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Diabetic Retinopathy caused by small hemorrhages and newly formed vessels in the retina decreased visual clarity usually both eyes are affected major cause of blindness Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Retinal Detachment separation of the retina from the choroid usually sudden and painless early symptoms are seeing light flashes and floaters more common with nearsightedness results in blindness if untreated Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Other common conditions that can affect the eye include: corneal abrasion or ulcer scleritis uveitis exophthalmos Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Globe of the Eye (cont’d.) Cancer of the Eye benign or malignant neoplasms usually metastases from other primary cancer retinoblastoma is most common primary malignancy of the eye in children Ocular melanoma is the most common ocular tumor in adults Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Chapter 5 Lesson 5.2 Functioning Organs of Hearing Hearing requires: vibratory or sound stimulus relay of sound/vibration to inner ear stimulation of tiny hairs in cochlea nerve impulses conducted to brain Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Normal Ear Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Functioning Organs of Hearing (cont’d.) Signs and symptoms that need medical attention: hearing loss ear pain or pressure ringing or buzzing noise (tinnitus) vertigo or dizziness nausea and vomiting Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear Disorders of Conduction impacted cerumen infective otitis externa swimmer’s ear otitis media otosclerosis Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Infective Otitis Externa Inflammation of external ear canal with signs and symptoms of: • pain, often severe • red, swollen canal • fever • itching • drainage, watery or purulent • hearing loss Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Otitis Media Inflammation of the middle ear with signs and symptoms of: • feeling of fullness or pressure • impaired hearing • pain, often severe • drainage, watery or purulent • fever • nausea and vomiting • dizziness Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Otitis Media Treatment includes: • analgesics for pain relief • decongestants to promote drainage • antibiotics (for suppurative otitis) • myringotomy: surgical removal of the fluid in severe cases Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Ménière Disease chronic disease of the inner ear syndrome includes: vertigo, tinnitus, progressive hearing loss and sensation of pressure sudden onset of episodes (vertigo, tinnitus, etc.) duration of hours to days treatment is symptomatic relief, not curative Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Labyrinthitis inflammation of labyrinth usually from viral or bacterial infection; can result from meningitis ruptured tympanic membrane tear or injury resulting from pressure, untreated middle ear infection, force or trauma Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Cholesteatoma cyst of infected skin cells within middle ear that erodes the cavity and ossicles Mastoiditis inflammation of the mastoid bone from untreated acute otitis media or associated with cholesteatoma Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Sensorineural Hearing Loss nerve impulses not transmitted to the brain due to damage to the cochlea or auditory nerve hearing loss can result from loud music, industrial noise, nearby explosion, medications, the aging process, and certain other causes irreversible, so prevention is essential Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Benign Paroxysmal Positional Vertigo (BPPV) A disorder of the vestibular system Symptoms include a spinning sensation, nausea, vomiting, involuntary eye movements, and unsteady gait Medications and positional head exercises may help reduce symptoms Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Disorders of the Ear (cont’d.) Cancer of the Ear benign or malignant tumors may originate from any part of the ear metastases from other primary cancer acoustic neuroma: a common tumor that surrounds eighth cranial nerve; usually benign, but may be recurrent Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc.