Flashcards in Chapter 64- Hearing/Balance Deck (70):
What are the two main functions of the ear?
Hearing and balance.
How is hearing conducted?
Hearing is conducted over two pathways: air and bone. Sounds transmitted by air conduction travel over the air-filled external and middle ear through vibration of the tympanic membrane and ossicles. Sounds transmitted by bone conduction travel directly through bone to the inner ear, bypassing the tympanic membrane and ossicles. Normally, air conduction is the more efficient pathway.
How is balance and equilibrium maintained?
Body balance is maintained by the cooperation of the muscles and joints of the body (proprioceptive system), the eyes (visual system), and the labyrinth (vestibular system).
What does an ear assessment include?
Assessment of hearing and balance involves inspection of the external, middle, and inner ear. Evaluation of gross hearing acuity also is included in every physical examination.
What does examination of the external ear involve?
Inspection of the external ear is a simple procedure, but it is often overlooked. The external ear is examined by inspection and direct palpation; the auricle and surrounding tissues should be inspected for deformities, lesions, and discharge, as well as size, symmetry, and angle of attachment to the head.
What is an otoscopic examination?
The tympanic membrane is inspected with an otoscope and indirect palpation with a pneumatic otoscope. The healthy tympanic membrane is pearly gray and is positioned obliquely at the base of the canal. The following landmarks are identified, if visible (see Fig. 64-2): the pars tensa, the umbo, the manubrium of the malleus, and its short process.
What are some hearing tests?
A general estimate of hearing can be made by assessing the patient’s ability to hear a whispered phrase, testing one ear at a time. The Weber and Rinne tests may be used to distinguish conductive loss from sensorineural loss when hearing is impaired.
What diagnostic tests are done for the ear?
What genetic syndromes are associated with hearing loss?
Waardenburg syndrome, Usher syndrome, Pendred syndrome, and Jervell and Lange-Nielsen syndrome.
What causes conductive hearing loss?
An external ear disorder, such as impacted cerumen, or a middle ear disorder, such as otitis media or otosclerosis.
What is mixed hearing loss?
Patients with mixed hearing loss have conductive loss and sensorineural loss, resulting from dysfunction of air and bone conduction.
What is deafness?
The partial or complete loss of the ability to hear.
How do loud noises cause hearing loss?
Loud, persistent noise has been found to cause constriction of peripheral blood vessels, increased blood pressure and heart rate (because of increased secretion of adrenalin), and increased gastrointestinal activity. Although research is needed to address the overall effects of noise on the human body, a quiet environment is more conducive to peace of mind. A person who is ill feels more at ease when noise is kept to a minimum.
What are risks for hearing loss?
• Family history of sensorineural impairment
• Congenital malformations of the cranial structure (ear)
• Low birth weight (<1,500 g)
• Use of ototoxic medications (e.g., gentamycin, loop diuretics)
• Recurrent ear infections
• Bacterial meningitis
• Chronic exposure to loud noises
• Perforation of the tympanic membrane
What is presbycusis?
Progressive, age-related hearing loss.
What are other age-related causes of hearing loss?
In addition to age-related changes, other factors can affect hearing in the older adult population, such as lifelong exposure to loud noises. Certain medications, such as aminoglycosides, aspirin, loop diuretics and platinum-based antineoplastic medications have ototoxic effects when kidney changes result in delayed medication excretion and increased levels of the medications in the blood.
What is cerumen impaction and how is it managed?
Accumulation of cerumen as a cause of hearing loss is especially significant in older adult patients. Cerumen can be removed by irrigation, suction, or instrumentation.
How are foreign bodies removed from the external auditory canal?
Removing a foreign body from the external auditory canal can be quite challenging. The three standard methods for removing foreign bodies are the same as those for removing cerumen: irrigation, suction, and instrumentation.
What is External Otitis?
Inflammation of the external auditory canal.
What causes External Otitis?
Causes include water in the ear canal (swimmer’s ear); trauma to the skin of the ear canal, permitting entrance of organisms into the tissues; and systemic conditions, such as vitamin deficiency and endocrine disorders. Bacterial or fungal infections are most frequently encountered. The most common bacterial pathogens associated with external otitis are Staphylococcus aureus and Pseudomonas species. The most common fungus isolated in both normal and infected ears is Aspergillus.
What are the symptoms of External Otitis?
Patients usually report pain; discharge from the external auditory canal; aural tenderness (usually not present in middle ear infections); and occasionally fever, cellulitis, and lymphadenopathy. Other symptoms may include pruritus and hearing loss or a feeling of fullness.
How is External Otitis managed?
The principles of therapy are aimed at relieving the discomfort, reducing the swelling of the ear canal, and eradicating the infection. Patients may require analgesic medications for the first 48 to 92 hours. Treatment most often includes antimicrobial or antifungal otic medications administered by dropper at room temperature. In bacterial infection, a combination antibiotic and corticosteroid agent may be used to soothe the inflamed tissues (Porth & Matfin, 2009).
What is malignant external otitis?
This is a progressive, debilitating, and occasionally fatal infection of the external auditory canal, the surrounding tissue, and the base of the skull. Pseudomonas aeruginosa is usually the infecting organism in patients with low resistance to infection (e.g., patients with acquired immunodeficiency virus).
What are exostoses and how are they managed?
Exostoses are small, hard, bony protrusions found in the lower posterior bony portion of the ear canal; they usually occur bilaterally. The skin covering the exostosis is normal. It is believed that exostoses are caused by an exposure to cold water, as in scuba diving or surfing. The usual treatment, if any, is surgical excision.
What happens if malignant tumors of the external ear are left untreated?
Malignant tumors also may occur in the external ear. Most common are basal cell carcinomas on the pinna and squamous cell carcinomas in the ear canal. If untreated, squamous cell carcinoma may spread through the temporal bone, causing facial nerve paralysis and hearing loss. Carcinomas must be treated surgically.
What causes tympanic membrane rupture?
Perforation of the tympanic membrane is usually caused by infection or trauma. Sources of trauma include skull fracture, explosive injury, or a severe blow to the ear. Less frequently, perforation is caused by foreign objects (e.g., cotton-tipped applicators, hairpins, keys) that have been pushed too far into the external auditory canal.
How are tympanic membrane perforations managed?
Although most tympanic membrane perforations heal spontaneously within weeks after rupture, some may take several months to heal.
Perforations that do not heal on their own may require surgery. The decision to perform a tympanoplasty (surgical repair of the tympanic membrane) is usually based on the need to prevent potential infection from water entering the ear or the desire to improve the patient’s hearing.
What is acute otitis media?
Inflammation in the middle ear lasting less than 6 weeks.
What are risk factors for Acute Otitis Media?
Risk factors for AOM include age (younger than 12 months), chronic upper respiratory infections medical conditions that predispose to ear infections (Down syndrome, cystic fibrosis, cleft palate), and chronic exposure to secondhand cigarette smoke.
How is Acute Otitis Media managed medically?
The outcome of AOM depends on the efficacy of therapy (the prescribed dose of an oral antibiotic and the duration of therapy), the virulence of the bacteria, and the physical status of the patient.
How is Acute Otitis Media managed?
A myringotomy (i.e., tympanotomy) is an incision in the tympanic membrane. The tympanic membrane is numbed with a local anesthetic agent such as phenol or by iontophoresis (i.e., in which electrical current flows through a lidocaine and epinephrine solution to numb the ear canal and tympanic membrane). The procedure is painless and takes less than 15 minutes. Under microscopic guidance, an incision is made through the tympanic membrane to relieve pressure and to drain serous or purulent fluid from the middle ear.
What is serous otitis media?
middle ear effusion: fluid in the middle ear without evidence of infection
What are the symptoms of serous otitis media?
Patients may complain of hearing loss, fullness in the ear or a sensation of congestion, or popping and crackling noises that occur as the eustachian tube attempts to open. The tympanic membrane appears dull on otoscopy, and air bubbles may be visualized in the middle ear. Usually, the audiogram shows a conductive hearing loss.
How is serous otitis media managed?
Serous otitis media need not be treated medically unless infection (i.e., AOM) occurs. Corticosteroids in small doses may decrease the edema of the eustachian tube in cases of barotrauma. Decongestants have not proved to be effective. A Valsalva maneuver, which forcibly opens the eustachian tube by increasing nasopharyngeal pressure, may be cautiously performed; this maneuver may cause worsening pain or perforation of the tympanic membrane.
What is chronic otitis media?
Repeated episodes of acute otitis media causing irreversible tissue damage and persistent tympanic membrane perforation.
What are the symptoms of chronic otitis media?
Symptoms may be minimal, with varying degrees of hearing loss and a persistent or intermittent, foul-smelling otorrhea. Pain is not usually experienced, except in cases of acute mastoiditis, when the postauricular area is tender and may be erythematous and edematous. Otoscopic examination may show a perforation, and cholesteatoma can be identified as a white mass behind the tympanic membrane or coming through to the external canal from a perforation.
What is cholesteatoma?
A tumor of the middle ear or mastoid, or both, that can destroy structures of the temporal bone.
How is chronic otitis media handled?
Local treatment for chronic otitis media consists of careful suctioning of the ear under otoscopic guidance. Instillation of antibiotic drops or application of antibiotic powder is used to treat purulent discharge. Systemic antibiotic agents are prescribed only in cases of acute infection.
Surgical procedures, including tympanoplasty, ossiculoplasty, and mastoidectomy, are used if medical treatments are ineffective.
What is tympanoplasty?
The most common surgical procedure for chronic otitis media is tympanoplasty, or surgical reconstruction of the tympanic membrane.
What is an ossiculoplasty?
Surgical reconstruction of the middle ear bones to restore hearing.
What is a mastoidectomy?
The objectives of mastoid surgery are to remove the cholesteatoma, gain access to diseased structures, and create a dry (noninfected) and healthy ear. If possible, the ossicles are reconstructed during the initial surgical procedure. Occasionally, extensive disease or damage dictates that this be performed as part of a two-stage operation.
What is otosclerosis?
A condition characterized by abnormal spongy bone formation around the stapes.
How does otosclelrosis manifest?
Otosclerosis may involve one or both ears and manifests as a progressive conductive or mixed hearing loss. The patient may or may not complain of tinnitus. Otoscopic examination usually reveals a normal tympanic membrane. Bone conduction is better than air conduction on Rinne testing. The audiogram confirms conductive hearing loss or mixed loss, especially in the low frequencies.
How is otosclerosis managed?
There is no evidence that any nonsurgical treatments are effective for treating otosclerosis. One of two surgical procedures may be performed: the stapedectomy or the stapedotomy.
What are two other masses of the middle ear?
Other than cholesteatoma, masses in the middle ear are rare. Glomus tympanicum is a tumor that arises from Jacobson’s nerve (in the temporal bone of the skull) and remains limited to the middle ear. On otoscopy, a red blemish on or behind the tympanic membrane is seen. Glomus jugulare tumors are rarely malignant; however, because of their location, treatment may be necessary to relieve symptoms. The treatment is surgical excision, except in poor surgical candidates, in whom radiation therapy is used.
What is motion sickness?
Motion sickness is a disturbance of equilibrium caused by constant motion. For example, it can occur aboard a ship, while riding on a merry-go-round or swing, or in a car (Herron, 2010).
How does motion sickness manifest and how is it medically managed?
The syndrome manifests itself in sweating, pallor, nausea, and vomiting caused by vestibular overstimulation. These manifestations may persist for several hours after the stimulation stops.
Over-the-counter antihistamines such as dimenhydrinate (Dramamine) or meclizine (Antivert) may provide some relief of nausea and vomiting by blocking the conduction of the vestibular pathway of the inner ear. Anticholinergic medications, such as scopolamine patches (Transderm Scop), may also be effective because they antagonize the histamine response.
What is Ménière’s Disease?
Ménière’s disease: condition of the inner ear characterized by a triad of symptoms: episodic vertigo, tinnitus, and fluctuating sensorineural hearing loss.
How does Ménière's disease manifest?
Ménière’s disease is characterized by a triad of symptoms: episodic vertigo, tinnitus (unwanted noises in the head or ear), and fluctuating sensorineural hearing loss. It may also include a feeling of pressure or fullness in the ear and incapacitating vertigo, often accompanied by nausea and vomiting.
How is Ménière’s Disease diagnosed?
Vertigo is usually the most troublesome complaint related to Ménière’s disease. A careful history is taken to determine the frequency, duration, severity, and character of the vertigo attacks. Physical examination findings are usually normal, with the exception of those of cranial nerve VIII.
How is Ménière’s Disease managed?
Most patients with Ménière’s disease can be successfully treated with diet and medication. Many patients can control their symptoms by adhering to a low-sodium (1,000 to 1,500 mg/day or less) diet.
How is Ménière’s Disease managed medically?
Pharmacologic therapy for Ménière’s disease consists of antihistamines, such as meclizine, which shortens the attack (NIDCD, 2010). Tranquilizers such as diazepam (Valium) may be used in acute instances to help control vertigo. Antiemetic agents such as promethazine (Phenergan) suppositories help control the nausea and vomiting and the vertigo because of their antihistamine effect. Diuretic therapy (e.g., hydrochlorothiazide [Dyazide], triamterene [Dyrenium]) may relieve symptoms by lowering the pressure in the endolymphatic system. Intratympanic injection of gentamicin (Garamycin) is used to cause ablation of the vestibular hair cells; however, the risk of significant hearing loss is high (NIDCD, 2010).
How is Ménière’s Disease surgically managed?
Surgical procedures include endolymphatic sac procedures and vestibular nerve section (NIDCD, 2010).
What is endolymphatic sac decompression?
Endolymphatic sac decompression, or shunting, theoretically equalizes the pressure in the endolymphatic space.
What is vestibular nerve sectioning?
Vestibular nerve sectioning provides the greatest success rate (approximately 98%) in eliminating the attacks of vertigo. It can be performed by a translabyrinthine approach (i.e., through the hearing mechanism) or in a manner that can conserve hearing (i.e., suboccipital or middle cranial fossa), depending on the degree of hearing loss.
What is Benign Paroxysmal Positional Vertigo?
Benign paroxysmal positional vertigo is a brief period of incapacitating vertigo that occurs when the position of the patient’s head is changed with respect to gravity, typically by placing the head back with the affected ear turned down (Nelson & Viire, 2009; NIDCD, 2009). The onset is sudden and followed by a predisposition for positional vertigo, usually for hours to weeks but occasionally for months or years.
What causes benign paroxysmal positional vertigo?
Benign paroxysmal positional vertigo is thought to be due to the disruption of debris within the semicircular canal. This debris is formed from small crystals of calcium carbonate from the inner ear structure (the utricle).
How is Benign Paroxysmal Positional Vertigo treated?
Bed rest is recommended for patients with acute symptoms. Repositioning techniques can be used to treat vertigo. The canalith repositioning procedure, also known as the Epley maneuver, is commonly used.
Patients with acute vertigo may be treated with meclizine for 1 to 2 weeks. After this time, the meclizine is stopped and the patient is reassessed. Patients who continue to have severe positional vertigo may be premedicated with prochlorperazine (Compazine) 1 hour before the canalith repositioning procedure is performed.
What is tinnitus?
Tinnitus is a symptom of an underlying disorder of the ear that is associated with hearing loss.
What is labrynthitis?
Inflammation of the labyrinth of the inner ear
How does labrynthitis manifest?
Labyrinthitis is characterized by a sudden onset of incapacitating vertigo, usually with nausea and vomiting, various degrees of hearing loss, and possibly tinnitus. The first episode is usually the worst; subsequent attacks, which usually occur over a period of several weeks to months, are less severe.
How is labrynthitis treated?
Treatment of bacterial labyrinthitis includes IV antibiotic therapy, fluid replacement, and administration of an antihistamine (e.g., meclizine) and antiemetic medications. Treatment of viral labyrinthitis is based on the patient’s symptoms.
What substances are known to be ototoxic?
• Diuretic agents: ethacrynic acid, furosemide, acetazolamide
• Chemotherapeutic (antineoplastic) agents: cisplatin, nitrogen mustard, carboplatin
• Antimalarial agents: quinine, chloroquine
• Anti-inflammatory agents: salicylates (aspirin), indomethacin
• Chemicals: alcohol, arsenic
• Aminoglycoside antibiotic agents: amikacin, gentamicin, kanamycin, netilmicin, neomycin, streptomycin, tobramycin
• Other antibiotic agents: erythromycin, minocycline, polymyxin B, vancomycin
• Metals: gold, mercury, lead
What are acoustic neuromas?
Acoustic neuromas are slow-growing, benign tumors of cranial nerve VIII, usually arising from the Schwann cells of the vestibular portion of the nerve.
How do acoustic neuromas manifest?
The most common assessment findings of patients with acoustic neuromas are unilateral tinnitus and hearing loss with or without vertigo or balance disturbance.
How are acoustic neuromas managed?
Conservative treatment is recommended for patients with tumors less than 1.5 cm and in those who are older. In addition, routine monitoring is recommended for these patients (McDonald, 2011). For low-risk patients, surgical removal of the acoustic tumor is the treatment of choice because these tumors do not respond well to radiation or chemotherapy.
What is the purpose of aural rehabilitation?
If hearing loss is permanent or cannot be treated by medical or surgical means or if the patient elects not to undergo surgery, aural rehabilitation may be beneficial. The purpose of aural rehabilitation is to maximize the communication skills of the person with hearing impairment. Aural rehabilitation includes auditory training, speech reading, speech training, and the use of hearing aids and hearing guide dogs.
What is a hearing aid?
A hearing aid is a device through which speech and environmental sounds are received by a microphone, converted to electrical signals, amplified, and reconverted to acoustic signals.
What are several types of implanted hearing devices?
There are two types of implantable hearing aids. The bone-anchored hearing aid (BAHA) is implanted behind the ear in the mastoid area. The middle ear implantation (MEI) is implanted in the middle ear cavity. The BAHA is used for conductive or mixed hearing loss, whereas the MEI is used for sensorineural hearing loss.
The FDA has also approved the semi-implantable Vibrant Soundbridge (electromagnetic) and the total implantable Envoy Esteem (piezoelectric) devices for use in the United States. The Vibrant Soundbridge has an external device attached to the postauricular bone that transmits sound to the magnet in the middle ear that is attached to the long process of the incus.
A cochlear implant is an auditory prosthesis used for people with profound sensorineural hearing loss bilaterally who do not benefit from conventional hearing aids. The hearing loss may be congenital or acquired.