Chapter 7 The Sensory Systems 279 George and his friends have been swimming in a nearby lake on weekends during the summer. They enjoy swinging from a rope tied to a tree on the bank of the lake and plunging into deep, cold water. On the day after one of these swimming excursions, George finds that he has a definite pain coming from inside one of his ears. He has no other symptoms. As you read this section, try to determine which of the following conditions George most likely has. A. Tinnitus B. External Otitis C. Otitis media D. Labyrinthitis CLINICAL CASE STUDY Check Your Understanding 1. What are the two functions of the ear? 2. What is the function of cerumen? 3. List the ossicles and tell why they are important. 4. Which structure in the inner ear controls equilibrium? Disorders and Infections of the Ear A variety of conditions can affect hearing or balance. This section addresses some of the most common disorders and infections of the ear. The etiology (cause), strategies for prevention, pathology (clinical characteristics), diagnosis (keys for identifying the condition), and common treatments for these disorders and infections of the ear are summarized in Figure 7.15. Disorders and Infections of the Ear Etiology Prevention Pathology Diagnosis Treatment Deafness injury to middle or inner ear, chronic exposure to loud noise, excessive earwax, scarring of tympanic membrane, damage to auditory nerve or auditory region of brain avoid exposure to loud noise, keep ears free of excess earwax partial or complete loss of hearing physical exam, hearing tests remove wax blockage, surgical procedures, hearing aid, cochlear implant Tinnitus damage to hair cells in organ of Corti, causing them to move randomly avoid exposure to loud sound avoid overuse of certain medications, such as NSAIDs ringing sound in the ears physical exam, hearing test, imaging test treat underlying health problem, noise suppression, medications External otitis (swimmer’s ear) bacterial or fungal infection of the auditory canal avoid ear immersion in water irrigate ear with mild alcohol solution after swimming itching, pain, fever, temporary hearing loss physical exam, ear exam cleaning of the ear canal, eardrops for infection, oral medication for pain Otitis media (middle ear infection) bacterial or viral infection of middle ear can result from cold or allergy that causes congestion and swelling of the nasal passages, throat, and Eustachian tubes keep ears clean and dry use precautions to avoid colds and allergic reactions pain, swelling, production of fluid or pus from ear physical exam, ear exam antibiotics and pain medication, as indicated Labyrinthitis (inner ear infection) inflammation of a vestibular nerve to the inner ear can result from infections of the ear or systemic infections maintain healthy lifestyle avoid stress dizziness, nausea, loss of hearing, vertigo, loss of balance, tinnitus physical exam tests of hearing and blood, imaging tests antihistamines, medications to reduce dizziness and nausea, sedatives, corticosteroids Figure 7.15 Goodheart-Willcox Publisher Copyright Goodheart-Willcox Co., Inc.