ESSENTIALS OF DIAGNOSIS
Three main types of hearing loss: conductive, sensory, and neural.
Most commonly due to cerumen impaction, transient eustachian tube dysfunction associated with upper respiratory tract infection, or age-related hearing loss.
Classification & Epidemiology
Table 8–1 categorizes hearing loss as normal, mild, moderate, severe, and profound and outlines the vocal equivalent as well as the decibel range.
Table 8–1.Hearing loss classification. |Favorite Table|Download (.pdf) Table 8–1. Hearing loss classification.
|Classification ||Vocal Equivalent ||Decibel (dB) Range |
|Normal ||Soft whisper ||0–20 dB |
|Mild ||Soft spoken voice ||20–40 dB |
|Moderate ||Normal spoken voice ||40–60 dB |
|Severe ||Loud spoken voice ||60–80 dB |
|Profound ||Shout ||> 80 dB |
A. Conductive Hearing Loss
Conductive hearing loss results from dysfunction of the external or middle ear. There are four mechanisms, each resulting in impairment of the passage of sound vibrations to the inner ear: (1) obstruction (eg, cerumen impaction), (2) mass loading (eg, middle ear effusion), (3) stiffness effect (eg, otosclerosis), and (4) discontinuity (eg, ossicular disruption). Conductive losses in adults are most commonly due to cerumen impaction or transient eustachian tube dysfunction associated with upper respiratory tract infection. Persistent conductive losses usually result from chronic ear infection, trauma, or otosclerosis. Conductive hearing loss is often correctable with medical or surgical therapy—or in some cases both.
Sensory and neural causes of hearing loss are difficult to differentiate due to testing methodology, thus often referred to as “sensorineural.” Sensory hearing loss results from deterioration of the cochlea, usually due to loss of hair cells from the organ of Corti. Sensorineural losses in adults are common. The most common form is a gradually progressive, predominantly high-frequency loss with advancing age (presbyacusis). Additional common causes include excessive noise exposure, head trauma, and systemic diseases. An individual’s genetic make-up influences all of these causes of hearing loss. Sensory hearing loss is usually not correctable with medical or surgical therapy but often may be prevented or stabilized. An exception is a sudden sensory hearing loss, which may respond to corticosteroids if delivered within several weeks of onset.
et al. Current concepts in age-related hearing loss: epidemiology and mechanistic pathways. Hear Res. 2013 Sep;303:30–8.
Neural hearing loss occurs with lesions involving the eighth nerve, auditory nuclei, ascending tracts, or auditory cortex. It is the least common clinically recognized cause of hearing loss. Causes include acoustic neuroma, multiple sclerosis, and auditory neuropathy.
et al. Auditory neuropathy/dyssynchrony revisited. B-ENT. 2014;10(2):105–12.
et al. Age-related changes in the central auditory system. Cell Tissue Res. 2015 Jul;361(1):337–58.
Evaluation of Hearing (Audiology)
In a quiet room, the hearing level may be estimated by having the patient repeat aloud words presented in a soft whisper, a normal spoken voice, or a shout. A 512-Hz tuning fork is useful in differentiating conductive from sensorineural losses. In the Weber test, the tuning fork is placed on the forehead or front teeth. In conductive losses, the sound appears louder in the poorer-hearing ear, whereas in sensorineural losses it radiates to the better side. In the Rinne test, the tuning fork is placed alternately on the mastoid bone and in front of the ear canal. In conductive losses greater than 25 dB, bone conduction exceeds air conduction; in sensorineural losses, the opposite is true.
Formal audiometric studies are performed in a soundproofed room. Pure-tone thresholds in decibels (dB) are obtained over the range of 250–8000 Hz for both air and bone conduction. Conductive losses create a gap between the air and bone thresholds, whereas in sensorineural losses, both air and bone thresholds are equally diminished. Speech discrimination measures the clarity of hearing, reported as percentage correct (90–100% is normal). The site of the lesion responsible for sensorineural loss (cochlea versus central auditory system) may be determined with auditory brainstem-evoked responses; however, an MRI scan is preferred for its better sensitivity and specificity in the evaluation of central lesions.
Every patient who complains of a hearing loss should be referred for audiologic evaluation unless the cause is easily remediable (eg, cerumen impaction, otitis media). Because idiopathic sudden sensorineural hearing loss requires treatment (corticosteroids) within a limited several-week time period, any new-onset hearing loss without obvious ear pathology needs an immediate audiometric referral. Routine audiologic screening is recommended for adults who have been exposed to potentially injurious levels of noise or in those who have reached the age of 65, after which screening evaluations may be done every few years.
Patients with hearing loss not correctable by medical therapy may benefit from hearing amplification. Contemporary hearing aids are comparatively free of distortion and have been miniaturized to the point where they often may be contained entirely within the ear canal or lie inconspicuously behind the ear. To optimize the benefit, a hearing aid must be carefully selected to conform to the nature of the hearing loss. Digitally programmable hearing aids are widely available and allow optimization of speech intelligibility and improved performance in difficult listening circumstances. Aside from hearing aids, many assistive devices are available to improve comprehension in individual and group settings, to help with hearing television and radio programs, and for telephone communication.
For patients with conductive loss or unilateral profound sensorineural loss, bone-conducting hearing aids directly stimulate the ipsilateral cochlea (for conductive losses) or contralateral ear (profound unilateral sensorineural loss).
For patients with severe to profound sensory hearing loss, the cochlear implant—an electronic device that is surgically implanted into the cochlea to stimulate the auditory nerve—offers socially beneficial auditory rehabilitation to most adults with acquired deafness and children with congenital or genetic deafness. New trends in cochlear implantation include its use for patients with only partial deafness, preserving residual hearing and allowing both acoustic and electrical hearing in the same ear.
et al. Cochlear implantation in adults: a systematic review and meta-analysis. JAMA Otolaryngol Head Neck Surg. 2013 Mar;139(3):265–72.
Disorders of the auricle are for the most part dermatologic. Skin cancers due to sun exposure are common and may be treated with standard techniques. Traumatic auricular hematoma must be recognized and drained to prevent significant cosmetic deformity (cauliflower ear) or canal blockage resulting from dissolution of supporting cartilage. Similarly, cellulitis of the auricle must be treated promptly to prevent development of perichondritis and its resultant deformity. Relapsing polychondritis is a rheumatologic disorder often associated with recurrent, frequently bilateral, painful episodes of auricular erythema and edema. Treatment with corticosteroids may help forestall cartilage dissolution. Respiratory compromise may occur as a result of progressive involvement of the cartilaginous tracheobronchial tree. Chondritis and perichondritis may be differentiated from auricular cellulitis by sparing of involvement of the lobule, which does not contain cartilage.
et al. Red ear syndrome: literature review and a pediatric case report. Int J Pediatr Otorhinolaryngol. 2015 Mar;79(3):281–5.
et al. Open surgical management of auricular haematoma: incision, evacuation and mattress sutures. J Laryngol Otol. 2015 May;129(5):496–501.
DISEASES OF THE EAR CANAL
Cerumen is a protective secretion produced by the outer portion of the ear canal. In most persons, the ear canal is self-cleansing. Recommended hygiene consists of cleaning the external opening with a washcloth over the index finger without entering the canal itself. In most cases, cerumen impaction is self-induced through ill-advised attempts at cleaning the ear. It may be relieved with detergent ear drops (eg, 3% hydrogen peroxide; 6.5% carbamide peroxide), mechanical removal, suction, or irrigation. Irrigation is performed with water at body temperature to avoid a vestibular caloric response. The stream should be directed at the posterior ear canal wall adjacent to the cerumen plug. Irrigation should be performed only when the tympanic membrane is known to be intact.
Use of jet irrigators designed for cleaning teeth (eg, WaterPik) for wax removal should be avoided since they may result in tympanic membrane perforations. Following professional irrigation, the ear canal should be thoroughly dried (eg, by instilling isopropyl alcohol or using a hair blow-dryer on low-power setting) to reduce the likelihood of inducing external otitis. Specialty referral for cleaning under microscopic guidance is indicated when the impaction is frequently recurrent, has not responded to routine measures, or if the patient has a history of chronic otitis media or tympanic membrane perforation.
et al. Impacted cerumen or something else? J Fam Pract. 2014 Apr;63(4):180.
Foreign bodies in the ear canal are more frequent in children than in adults. Firm materials may be removed with a loop or a hook, taking care not to displace the object medially toward the tympanic membrane; microscopic guidance is helpful. Aqueous irrigation should not be performed for organic foreign bodies (eg, beans, insects), because water may cause them to swell. Living insects are best immobilized before removal by filling the ear canal with lidocaine.
et al. Hazardous complications of animate foreign bodies in otology practice. J Laryngol Otol. 2015 Jun;129(6):540–3.
ESSENTIALS OF DIAGNOSIS
Painful erythema and edema of the ear canal skin.
Often with purulent exudate.
May evolve into osteomyelitis of the skull base, often called malignant external otitis, particularly in the diabetic or immunocompromised patient.
External otitis presents with otalgia, frequently accompanied by pruritus and purulent discharge. There is often a history of recent water exposure (ie, swimmer’s ear) or mechanical trauma (eg, scratching, cotton applicators). External otitis is usually caused by gram-negative rods (eg, Pseudomonas, Proteus) or fungi (eg, Aspergillus), which grow in the presence of excessive moisture. Persistent external otitis in the diabetic or immunocompromised patient may evolve into osteomyelitis of the skull base, often called malignant external otitis. Usually caused by Pseudomonas aeruginosa, osteomyelitis begins in the floor of the ear canal and may extend into the middle fossa floor, the clivus, and even the contralateral skull base.
Examination reveals erythema and edema of the ear canal skin, often with a purulent exudate. Manipulation of the auricle often elicits pain. Because the lateral surface of the tympanic membrane is ear canal skin, it is often erythematous. However, in contrast to acute otitis media, it moves normally with pneumatic otoscopy. When the canal skin is very edematous, it may be impossible to visualize the tympanic membrane. Malignant external otitis, which usually occurs in patients with immune compromise or diabetes mellitus, typically presents with persistent foul aural discharge, granulations in the ear canal, deep otalgia, and in advanced cases, progressive cranial nerve palsies involving nerves VI, VII, IX, X, XI, or XII. Diagnosis is confirmed by the demonstration of osseous erosion on CT and radionuclide scanning.
Fundamental to the treatment of external otitis is protection of the ear from additional moisture and avoidance of further mechanical injury by scratching. In cases of swimmer’s ear, acidification with a drying agent (ie, a 50/50 mixture of isopropyl alcohol/white vinegar) after getting moisture into the ear is often helpful. When infected, acidic otic antibiotic drops that contain either an aminoglycoside or fluoroquinolone antibiotic, with or without corticosteroids, are usually effective (eg, neomycin sulfate, polymyxin B sulfate, and hydrocortisone). Purulent debris filling the ear canal should be gently removed to permit entry of the topical medication. Drops should be used abundantly (five or more drops three or four times a day) to penetrate the depths of the canal. When substantial edema of the canal wall prevents entry of drops into the ear canal, a wick is placed to facilitate entry of the medication. In recalcitrant cases—particularly when cellulitis of the periauricular tissue has developed—oral fluoroquinolones (eg, ciprofloxacin, 500 mg twice daily for 1 week) are the drugs of choice because of their effectiveness against Pseudomonas species. Any case of persistent otitis externa in an immunocompromised or diabetic individual must be referred for specialty evaluation.
Treatment of malignant external otitis is medical, requiring prolonged antipseudomonal antibiotic administration, often for several months. Although intravenous therapy is often required (eg, ciprofloxacin 200–400 mg every 12 hours), selected patients may be treated with oral ciprofloxacin (500–1000 mg twice daily), which has proved effective against many of the causative Pseudomonas strains. To avoid relapse, antibiotic therapy should be continued, even in the asymptomatic patient, until gallium scanning indicates a marked reduction in the inflammatory process. Surgical debridement of infected bone is reserved for cases of deterioration despite medical therapy.
et al. Malignant otitis externa: evolving pathogens and implications for diagnosis and treatment. Otolaryngol Head Neck Surg. 2014 Mar 26;151(1):112–6.
et al; American Academy of Otolaryngology—Head and Neck Surgery Foundation. Clinical practice guideline: acute otitis externa executive summary. Otolaryngol Head Neck Surg. 2014 Feb;150(2):161–8.
Pruritus of the external auditory canal, particularly at the meatus, is a common problem. While it may be associated with external otitis or with dermatologic conditions, such as seborrheic dermatitis and psoriasis, most cases are self-induced, either from excoriation or by overly zealous ear cleaning. To permit regeneration of the protective cerumen blanket, patients should be instructed to avoid use of soap and water or cotton swabs in the ear canal and avoid any scratching. Patients with excessively dry canal skin may benefit from application of mineral oil, which helps counteract dryness and repel moisture. When an inflammatory component is present, topical application of a corticosteroid (eg, 0.1% triamcinolone) may be beneficial.
et al. Dermatologic diseases of the external ear. Clin Dermatol. 2014 Jan–Feb;32(1):141–52.
Bony overgrowths of the ear canal are a frequent incidental finding and occasionally have clinical significance. Clinically, they present as skin-covered bony mounds in the medial ear canal obscuring the tympanic membrane to a variable degree. Solitary osteomas are of no significance as long as they do not cause obstruction or infection. Multiple exostoses, which are generally acquired from repeated exposure to cold water (eg, “surfer’s ear”) may progress and require surgical removal.
et al. Canalplasty for exostoses with maximal skin preservation with temporoparietal fascia grafting and use of bone wax for Skin flap protection: a retrospective case Series. Ann Otol Rhinol Laryngol. 2015 Dec;124(12):978–86.
et al. Birth and evolution of chiselling and drilling techniques for removing ear canal exostoses. Otol Neurotol. 2016 Jan;37(1):109–114.
The most common neoplasm of the ear canal is squamous cell carcinoma. When an apparent otitis externa does not resolve on therapy, a malignancy should be suspected and biopsy performed. This disease carries a very high 5-year mortality rate because the tumor tends to invade the lymphatics of the cranial base and must be treated with wide surgical resection and radiation therapy. Adenomatous tumors, originating from the ceruminous glands, generally follow a more indolent course.
et al. Radiation-associated malignancies of the ear canal and temporal bone. Laryngoscope. 2015 May;125(5):1198–204.
et al. Temporal bone carcinoma. Current diagnostic, therapeutic, and prognostic concepts. J Surg Oncol. 2014 Sep;110(4):383–92.
et al. A critical look at persistent problems in the diagnosis, staging and treatment of temporal bone carcinoma. Cancer Treat Rev. 2015 Dec;41(10):821–6.
DISEASES OF THE EUSTACHIAN TUBE
1. Eustachian Tube Dysfunction
The tube that connects the middle ear to the nasopharynx—the eustachian tube—provides ventilation and drainage for the middle ear cleft. It is normally closed, opening only during swallowing or yawning. When eustachian tube function is compromised, air trapped within the middle ear becomes absorbed and negative pressure results. The most common causes of eustachian tube dysfunction are diseases associated with edema of the tubal lining, such as viral upper respiratory tract infections and allergy. The patient usually reports a sense of fullness in the ear and mild to moderate impairment of hearing. When the tube is only partially blocked, swallowing or yawning may elicit a popping or crackling sound. Examination may reveal retraction of the tympanic membrane and decreased mobility on pneumatic otoscopy. Following a viral illness, this disorder is usually transient, lasting days to weeks. Treatment with systemic and intranasal decongestants (eg, pseudoephedrine, 60 mg orally every 4 hours; oxymetazoline, 0.05% spray every 8–12 hours) combined with autoinflation by forced exhalation against closed nostrils may hasten relief. Autoinflation should not be recommended to patients with active intranasal infection, since this maneuver may precipitate middle ear infection. Allergic patients may also benefit from desensitization or intranasal corticosteroids (eg, beclomethasone dipropionate, two sprays in each nostril twice daily for 2–6 weeks). Air travel, rapid altitudinal change, and underwater diving should be avoided during an active phase of the disease.
Conversely, an overly patent eustachian tube, termed “patulous eustachian tube,” is a relatively uncommon problem though may be quite distressing. Typical complaints include fullness in the ear and autophony, an exaggerated ability to hear oneself breathe and speak. A patulous eustachian tube may develop during rapid weight loss, or it may be idiopathic. In contrast to a hypofunctioning eustachian tube, the aural pressure is often made worse by exertion and may diminish during an upper respiratory tract infection. Although physical examination is usually normal, respiratory excursions of the tympanic membrane may occasionally be detected during vigorous breathing. Treatment includes avoidance of decongestant products, insertion of a ventilating tube to reduce the outward stretch of the eardrum during phonation and, rarely, surgical procedure in the eustachian tube.
et al. Systematic review of the limited evidence base for treatments of Eustachian tube dysfunction: a health technology assessment. Clin Otolaryngol. 2014 Feb;39(1):6–21.
et al. Balloon eustachian tuboplasty: a systematic review. Otolaryngol Head Neck Surg. 2015 Mar;152(3):383–92.
Prolonged eustachian tube dysfunction with resultant negative middle ear pressure may cause a transudation of fluid. This condition, known as serous otitis media, is especially common in children because their eustachian tubes are narrower and more horizontal in orientation than those in adults. Serous otitis media is less common in adults, in whom it usually occurs after an upper respiratory tract infection, with barotrauma, or with chronic allergic rhinitis. In any adult with persistent unilateral serous otitis media, nasopharyngeal carcinoma must be excluded. The tympanic membrane in serous otitis media is dull and hypomobile, occasionally accompanied by air bubbles in the middle ear and conductive hearing loss. The treatment of serous otitis media is similar to that for eustachian tube dysfunction. A short course of oral corticosteroids (eg, prednisone, 40 mg/day for 7 days) has been advocated by some clinicians, as have oral antibiotics (eg, amoxicillin, 250 mg three times daily for 7 days)—or even a combination of the two. The role of these regimens remains controversial, but they are probably of little lasting benefit. When medication fails to bring relief after several months, a ventilating tube placed through the tympanic membrane may restore hearing and alleviate the sense of aural fullness. Endoscopically guided laser expansion of the nasopharyngeal orifice of the eustachian tube may improve function in recalcitrant cases.
MF. Epidemiology and pathogenesis of otitis media: construction of a phenotype landscape. Audiol Neurootol. 2014;19(3):210–23.
et al. Surgical treatments for otitis media with effusion: a systematic review. Pediatrics. 2014 Feb;133(2):296–311.
Persons with poor eustachian tube function (eg, congenital narrowness or acquired mucosal edema) may be unable to equalize the barometric stress exerted on the middle ear by air travel, rapid altitudinal change, or underwater diving. The problem is generally most acute during airplane descent, since the negative middle ear pressure tends to collapse and block the eustachian tube. Several measures are useful to enhance eustachian tube function and avoid otic barotrauma. The patient should be advised to swallow, yawn, and autoinflate frequently during descent, which may be painful if the eustachian tube collapses. Oral decongestants (eg, pseudoephedrine, 60–120 mg) should be taken several hours before anticipated arrival time so that they will be maximally effective during descent. Topical decongestants such as 1% phenylephrine nasal spray should be administered 1 hour before arrival.
For acute negative middle ear pressure that persists on the ground, treatment includes decongestants and attempts at autoinflation. Myringotomy (creation of a small eardrum perforation) provides immediate relief and is appropriate in the setting of severe otalgia and hearing loss. Repeated episodes of barotrauma in persons who must fly frequently may be alleviated by insertion of ventilating tubes.
Underwater diving may represent an even greater barometric stress to the ear than flying. The problem occurs most commonly during the descent phase, when pain develops within the first 15 feet if inflation of the middle ear via the eustachian tube has not occurred. Divers must descend slowly and equilibrate in stages to avoid the development of severely negative pressures in the tympanum that may result in hemorrhage (hemotympanum) or perilymphatic fistula. In the latter, the oval or round window ruptures, resulting in sensory hearing loss and acute vertigo. Emesis due to acute labyrinthine dysfunction can be very dangerous during an underwater dive. Sensory hearing loss or vertigo, which develops during the ascent phase of a saturation dive, may be the first (or only) symptom of decompression sickness. Immediate recompression will return intravascular gas bubbles to solution and restore the inner ear microcirculation. Patients should be warned to avoid diving when they have upper respiratory infections or episodes of nasal allergy. Tympanic membrane perforation is an absolute contraindication to diving, as the patient will experience an unbalanced thermal stimulus to the semicircular canals and may experience vertigo, disorientation, and even emesis.
et al. Barotrauma with extreme pressures in sport: from scuba to skydiving. Curr Sports Med Rep. 2014 Mar–Apr;13(2):107–12.
et al. Inner-ear decompression sickness: 'hubble-bubble' without brain trouble? Diving Hyperb Med. 2015 Jun;45(2):135–6.
DISEASES OF THE MIDDLE EAR
ESSENTIALS OF DIAGNOSIS
Otalgia, often with an upper respiratory tract infection.
Erythema and hypomobility of tympanic membrane.
Acute otitis media is a bacterial infection of the mucosally lined air-containing spaces of the temporal bone. Purulent material forms not only within the middle ear cleft but also within the pneumatized mastoid air cells and petrous apex. Acute otitis media is usually precipitated by a viral upper respiratory tract infection that causes eustachian tube obstruction. This results in accumulation of fluid and mucus, which becomes secondarily infected by bacteria. The most common pathogens are Streptococcus pneumoniae, Haemophilus influenzae, and Streptococcus pyogenes.
Acute otitis media is most common in infants and children, although it may occur at any age. Presenting symptoms and signs include otalgia, aural pressure, decreased hearing, and often fever. The typical physical findings are erythema and decreased mobility of the tympanic membrane. Occasionally, bullae will be seen on the tympanic membrane.
Rarely, when middle ear empyema is severe, the tympanic membrane can bulge outward. In such cases, tympanic membrane rupture is imminent. Rupture is accompanied by a sudden decrease in pain, followed by the onset of otorrhea. With appropriate therapy, spontaneous healing of the tympanic membrane occurs in most cases. When perforation persists, chronic otitis media may evolve. Mastoid tenderness often accompanies acute otitis media and is due to the presence of pus within the mastoid air cells. This alone does not indicate suppurative (surgical) mastoiditis. Frank swelling over the mastoid bone or the association of cranial neuropathies or central findings indicates severe disease requiring urgent care.
The treatment of acute otitis media is specific antibiotic therapy, often combined with nasal decongestants. The first-choice oral antibiotic treatment is amoxicillin (80–90 mg/kg/day divided twice daily) (or erythromycin [50 mg/kg/day]) plus sulfonamide (150 mg/kg/day) for 10 days. Alternatives useful in resistant cases are cefaclor (20–40 mg/kg/day) or amoxicillin-clavulanate (20–40 mg/kg/day) combinations.
Tympanocentesis for bacterial (aerobic and anaerobic) and fungal culture may be performed by any experienced physician. A 20-gauge spinal needle bent 90 degrees to the hub attached to a 3-mL syringe is inserted through the inferior portion of the tympanic membrane. Interposition of a pliable connecting tube between the needle and syringe permits an assistant to aspirate without inducing movement of the needle. Tympanocentesis is useful for otitis media in immunocompromised patients and when infection persists or recurs despite multiple courses of antibiotics.
Surgical drainage of the middle ear (myringotomy) is reserved for patients with severe otalgia or when complications of otitis (eg, mastoiditis, meningitis) have occurred.
Recurrent acute otitis media may be managed with long-term antibiotic prophylaxis. Single daily oral doses of sulfamethoxazole (500 mg) or amoxicillin (250 or 500 mg) are given over a period of 1–3 months. Failure of this regimen to control infection is an indication for insertion of ventilating tubes.
et al. Antibiotics for acute otitis media in children. Cochrane Database Syst Rev. 2015 Jun 23;6:CD000219.
ESSENTIALS OF DIAGNOSIS
Chronic otorrhea with or without otalgia.
Tympanic membrane perforation with conductive hearing loss.
Often amenable to surgical correction.
Chronic infection of the middle ear and mastoid generally develops as a consequence of recurrent acute otitis media, although it may follow other diseases and trauma. Perforation of the tympanic membrane is usually present. This may be accompanied by mucosal changes such as polypoid degeneration and granulation tissue and osseous changes such as osteitis and sclerosis. The bacteriology of chronic otitis media differs from that of acute otitis media. Common organisms include P aeruginosa, Proteus species, Staphylococcus aureus, and mixed anaerobic infections.
The clinical hallmark of chronic otitis media is purulent aural discharge. Drainage may be continuous or intermittent, with increased severity during upper respiratory tract infection or following water exposure. Pain is uncommon except during acute exacerbations. Conductive hearing loss results from destruction of the tympanic membrane or ossicular chain, or both.
The medical treatment of chronic otitis media includes regular removal of infected debris, use of earplugs to protect against water exposure, and topical antibiotic drops (ofoxacin 0.3% or ciprofloxacin with dexamethasone) for exacerbations. The activity of ciprofloxacin against Pseudomonas may help dry a chronically discharging ear when given in a dosage of 500 mg orally twice a day for 1–6 weeks.
Definitive management is surgical in most cases. Tympanic membrane repair may be accomplished with temporalis muscle fascia. Successful reconstruction of the tympanic membrane may be achieved in about 90% of cases, often with elimination of infection and significant improvement in hearing. When the mastoid air cells are involved by irreversible infection, they should be exenterated at the same time through a mastoidectomy.
et al. Why are ototopical aminoglycosides still first-line therapy for chronic suppurative otitis media? A systematic review and discussion of aminoglycosides versus quinolones. J Laryngol Otol. 2016 Jan;130(1):2–7.
et al. A systematic review of patient-reported outcome measures for chronic suppurative otitis media. Laryngoscope. 2015 Sep 15. [Epub ahead of print]
Complications of Otitis Media
Cholesteatoma is a special variety of chronic otitis media (Figure 8–1). The most common cause is prolonged eustachian tube dysfunction, with inward migration of the upper flaccid portion of the tympanic membrane. This creates a squamous epithelium-lined sac, which—when its neck becomes obstructed—may fill with desquamated keratin and become chronically infected. Cholesteatomas typically erode bone, with early penetration of the mastoid and destruction of the ossicular chain. Over time they may erode into the inner ear, involve the facial nerve, and on rare occasions spread intracranially. Otoscopic examination may reveal an epitympanic retraction pocket or a marginal tympanic membrane perforation that exudes keratin debris, or granulation tissue. The treatment of cholesteatoma is surgical marsupialization of the sac or its complete removal. This may require the creation of a “mastoid bowl” in which the ear canal and mastoid are joined into a large common cavity that must be periodically cleaned.
Cholesteatoma. (From Vladimir Zlinksy, MD, in Roy F. Sullivan, PhD: Audiology Forum: Video Otoscopy, www.RCSullivan.com; used with permission from Usatine RP, Smith MA, Mayeaux EJ Jr, Chumley H, Tysinger J. The Color Atlas of Family Medicine. McGraw-Hill, 2009.)
et al. A new theory on the pathogenesis of acquired cholesteatoma: mucosal traction. Laryngoscope. 2015 Aug;125(Suppl 4):S1–14.
et al. Current trends in the management of the complications of chronic otitis media with cholesteatoma. Curr Opin Otolaryngol Head Neck Surg. 2013 Oct;21(5):446–54.
Acute suppurative mastoiditis usually evolves following several weeks of inadequately treated acute otitis media. It is characterized by postauricular pain and erythema accompanied by a spiking fever. CT scan reveals coalescence of the mastoid air cells due to destruction of their bony septa. Initial treatment consists of intravenous antibiotics (eg, cefazolin 0.5–1.5 g every 6–8 hours) directed against the most common offending organisms (S pneumoniae, H influenzae, and S pyogenes), and myringotomy for culture and drainage. Failure of medical therapy indicates the need for surgical drainage (mastoidectomy).
The medial portion of the petrous bone between the inner ear and clivus may become a site of persistent infection when the drainage of its pneumatic cell tracts becomes blocked. This may cause foul discharge, deep ear and retro-orbital pain, and sixth nerve palsy (Gradenigo syndrome); meningitis may be a complication. Treatment is with prolonged antibiotic therapy (based on culture results) and surgical drainage via petrous apicectomy.
et al. Complications of chronic suppurative otitis media and their management: a single institution 12 years experience. Indian J Otolaryngol Head Neck Surg. 2015 Dec;67(4):353–60.
Facial palsy may be associated with either acute or chronic otitis media. In the acute setting, it results from inflammation of the seventh nerve in its middle ear segment, perhaps mediated through bacterially secreted neurotoxins. Treatment consists of myringotomy for drainage and culture, followed by intravenous antibiotics (based on culture results). The use of corticosteroids is controversial. The prognosis is excellent, with complete recovery in most cases.
Facial palsy associated with chronic otitis media usually evolves slowly due to chronic pressure on the seventh nerve in the middle ear or mastoid by cholesteatoma. Treatment requires surgical correction of the underlying disease. The prognosis is less favorable than for facial palsy associated with acute otitis media.
et al. Facial nerve paralysis in patients with chronic ear infections: surgical outcomes and radiologic analysis. Clin Exp Otorhinolaryngol. 2015 Sep;8(3):218–23.
E. Sigmoid Sinus Thrombosis
Trapped infection within the mastoid air cells adjacent to the sigmoid sinus may cause septic thrombophlebitis. This is heralded by signs of systemic sepsis (spiking fevers, chills), at times accompanied by signs of increased intracranial pressure (headache, lethargy, nausea and vomiting, papilledema). Diagnosis can be made noninvasively by magnetic resonance venography. Primary treatment is with intravenous antibiotics (based on culture results). Surgical drainage with ligation of the internal jugular vein may be indicated when embolization is suspected.
et al. Pediatric otogenic sigmoid sinus thrombosis: 12-Year experience. Int J Pediatr Otorhinolaryngol. 2014 Jun;78(6):930–3.
F. Central Nervous System Infection
Otogenic meningitis is by far the most common intracranial complication of ear infection. In the setting of acute suppurative otitis media, it arises from hematogenous spread of bacteria, most commonly H influenzae and S pneumoniae. In chronic otitis media, it results either from passage of infections along preformed pathways, such as the petrosquamous suture line, or from direct extension of disease through the dural plates of the petrous pyramid.
Epidural abscesses arise from direct extension of disease in the setting of chronic infection. They are usually asymptomatic but may present with deep local pain, headache, and low-grade fever. They are often discovered as an incidental finding at surgery. Brain abscess may arise in the temporal lobe or cerebellum as a result of septic thrombophlebitis adjacent to an epidural abscess. The predominant causative organisms are S aureus, S pyogenes, and S pneumoniae. Rupture into the subarachnoid space results in meningitis and often death. (See Chapter 30.)
et al. Complications of chronic suppurative otitis media and their management: a single institution 12 years experience. Indian J Otolaryngol Head Neck Surg. 2015 Dec;67(4):353–60.
Otosclerosis is a progressive disease with a marked familial tendency that affects the bony otic capsule. Lesions involving the footplate of the stapes result in increased impedance to the passage of sound through the ossicular chain, producing conductive hearing loss. This may be treated either through the use of a hearing aid or surgical replacement of the stapes with a prosthesis (stapedectomy). When otosclerotic lesions impinge on the cochlea (“cochlear otosclerosis”), permanent sensory hearing loss occurs.
et al. The pathophysiology of otosclerosis: review of current research. Hear Res. 2015 Dec;330(Pt A):51–6.
et al. A systematic review of the diagnostic value of CT imaging in diagnosing otosclerosis. Otol Neurotol. 2016 Jan;37(1):9–15.
4. Trauma to the Middle Ear
Tympanic membrane perforation may result from impact injury or explosive acoustic trauma (Figure 8–2). Spontaneous healing occurs in most cases. Persistent perforation may result from secondary infection brought on by exposure to water. Patients should be advised to wear earplugs while swimming or bathing during the healing period. Hemorrhage behind an intact tympanic membrane (hemotympanum) may follow blunt trauma or extreme barotrauma. Spontaneous resolution over several weeks is the usual course. When a conductive hearing loss greater than 30 dB persists for more than 3 months following trauma, disruption of the ossicular chain should be suspected. Middle ear exploration with reconstruction of the ossicular chain, combined with repair of the tympanic membrane when required, will usually restore hearing.
Traumatic perforation of the left tympanic membrane. (From William Clark, MD; reproduced, with permission, from Usatine RP, Smith MA, Mayeaux EJ Jr, Chumley H, Tysinger J. The Color Atlas of Family Medicine. McGraw-Hill, 2009.)
et al. Otologic assessment of blast and nonblast injury in returning Middle East-deployed service members. Laryngoscope. 2014 Jan;124(1):272–7.
Primary middle ear tumors are rare. Glomus tumors arise either in the middle ear (glomus tympanicum) or in the jugular bulb with upward erosion into the hypotympanum (glomus jugulare). They present clinically with pulsatile tinnitus and hearing loss. A vascular mass may be visible behind an intact tympanic membrane. Large glomus jugulare tumors are often associated with multiple cranial neuropathies, especially involving nerves VII, IX, X, XI, and XII. Treatment usually requires surgery, radiotherapy, or both. Pulsatile tinnitus thus warrants magnetic resonance angiography and venography to rule out a vascular mass.
et al. Adenomatous tumors of the middle ear. Otolaryngol Clin North Am. 2015 Apr;48(2):305–15.
Earache can be caused by a variety of otologic problems, but external otitis and acute otitis media are the most common. Differentiation of the two should be apparent by pneumatic otoscopy (see relevant sections on otitis externa and otitis media). Pain out of proportion to the physical findings may be due to herpes zoster oticus, especially when vesicles appear in the ear canal or concha. Persistent pain and discharge from the ear suggest osteomyelitis of the skull base or cancer, and patients with these complaints should be referred for specialty evaluation.
Nonotologic causes of otalgia are numerous. The sensory innervation of the ear is derived from the trigeminal, facial, glossopharyngeal, vagal, and upper cervical nerves. Because of this rich innervation, referred otalgia is quite frequent. Temporomandibular joint dysfunction is a common cause of referred ear pain. Pain is exacerbated by chewing or psychogenic grinding of the teeth (bruxism) and may be associated with dental malocclusion. Management includes soft diet, local heat to the masticatory muscles, massage, nonsteroidal anti-inflammatory medications, and dental referral. Repeated episodes of severe lancinating otalgia may occur in glossopharyngeal neuralgia. Treatment with carbamazepine (100–300 mg orally every 8 hours) often confers substantial symptomatic relief. Severe glossopharyngeal neuralgia, which is refractory to medical management, may respond to microvascular decompression of the ninth cranial nerve. Infections and neoplasia that involve the oropharynx, hypopharynx, and larynx frequently cause otalgia. Persistent earache demands specialty referral to exclude cancer of the upper aerodigestive tract.
DISEASES OF THE INNER EAR
Diseases of the cochlea result in sensory hearing loss, a condition that is usually irreversible. Most cochlear diseases result in bilateral symmetric hearing loss. The presence of unilateral or asymmetric sensorineural hearing loss suggests a lesion proximal to the cochlea. Lesions affecting the eighth cranial nerve and central auditory system are discussed in the section on neural hearing loss. The primary goals in the management of sensory hearing loss are prevention of further losses and functional improvement with amplification and auditory rehabilitation.
Presbyacusis, or age-related hearing loss, is the most frequent cause of sensory hearing loss and is progressive, predominantly high-frequency, and symmetrical. It is difficult to separate the various etiologic factors (eg, noise trauma, drug exposure) that may contribute to presbyacusis, but genetic predisposition and prior noise exposure appear to play an important role. Most patients notice a loss of speech discrimination that is especially pronounced in noisy environments. About 25% of people between the ages of 65 and 75 years and almost 50% of those over 75 experience hearing difficulties.
TN. Aging of the auditory system. Handb Clin Neurol. 2015;129:357–73.
et al. Progress and prospects in human genetic research into age-related hearing impairment. Biomed Res Int. 2014;2014:390601.
Noise trauma is the second most common cause of sensory hearing loss. Sounds exceeding 85 dB are potentially injurious to the cochlea, especially with prolonged exposures. The loss typically begins in the high frequencies (especially 4000 Hz) and progresses to involve the speech frequencies with continuing exposure. Among the more common sources of injurious noise are industrial machinery, weapons, and excessively loud music. Personal music devices (eg, MP3 and CD players) used at excessive loudness levels may also be potentially injurious. Monitoring noise levels in the workplace by regulatory agencies has led to preventive programs that have reduced the frequency of occupational losses. Individuals of all ages, especially those with existing hearing losses, should wear earplugs when exposed to moderately loud noises and specially designed earmuffs when exposed to explosive noises.
et al. Occupational noise exposure and hearing: a systematic review. Int Arch Occup Environ Health. 2015 Aug 7. [Epub ahead of print]
Head trauma has effects on the inner ear similar to those of severe acoustic trauma. Some degree of sensory hearing loss may occur following simple concussion and is frequent after skull fracture. Deployment of air bags during an automobile accident has also been associated with hearing loss.
TJ. Noise-induced hearing loss: a military perspective. Curr Opin Otolaryngol Head Neck Surg. 2014 Oct;22(5):384–7.
Ototoxic substances may affect both the auditory and vestibular systems. The most commonly used ototoxic medications are aminoglycosides; loop diuretics; and several antineoplastic agents, notably cisplatin. These medications may cause irreversible hearing loss even when administered in therapeutic doses. When using these medications, it is important to identify high-risk patients, such as those with preexisting hearing losses or kidney disease. Patients simultaneously receiving multiple ototoxic agents are at particular risk owing to ototoxic synergy. Useful measures to reduce the risk of ototoxic injury include serial audiometry, monitoring of serum peak and trough levels, and substitution of equivalent nonototoxic drugs whenever possible. Efforts are underway to develop strategies, known as ototoxic chemoprotection, using drugs that shield the inner ear from damage during ototoxic exposure.
It is possible for topical agents that enter the middle ear to be absorbed into the inner ear via the round window. When the tympanic membrane is perforated, use of potentially ototoxic ear drops (eg, neomycin, gentamicin) is best avoided.
et al. Ototoxicity (cochleotoxicity) classifications: a review. Int J Audiol. 2016 Feb;55(2):65–74.
et al. Pharmacotherapeutic options for treating adverse effects of cisplatin
chemotherapy. Expert Opin Pharmacother. 2015 Dec 17:1–10.
E. Sudden Sensory Hearing Loss
Idiopathic sudden loss of hearing in one ear may occur at any age, but typically, it occurs in persons over age 20 years. The cause is unknown; however, one hypothesis is that it results from a viral infection or a sudden vascular occlusion of the internal auditory artery. Prognosis is mixed, with many patients suffering permanent deafness in the involved ear, while others have complete recovery. Prompt treatment with corticosteroids has been shown to improve the odds of recovery. A common regimen is oral prednisone, 1 mg/kg/day, followed by a tapering dose over a 10-day period. Intratympanic administration of corticosteroids alone or in association with oral corticosteroids has been associated with an equal or more favorable prognosis in some reports. Because treatment appears to be most effective as close to the onset of the loss as possible, and appears not to be effective after 6 weeks, a prompt audiogram should be obtained in all patients who present with sudden hearing loss without obvious middle ear pathology.
et al. Intratympanic steroid therapy as a salvage treatment for sudden sensorineural hearing loss after failure of conventional therapy: a meta-analysis of randomized, controlled trials. Clin Ther. 2015 Jan 1;37(1):178–87.
et al. Oral vs intratympanic corticosteroid therapy for idiopathic sudden sensorineural hearing loss: a randomized trial. JAMA. 2011 May 25;305(20):2071–9.
et al. Controversies in the management of sudden sensorineural hearing loss (SSNHL): an evidence based review. Clin Otolaryngol. 2015 Jun;40(3):176–82.
et al. Steroids for idiopathic sudden sensorineural hearing loss. Cochrane Database Syst Rev. 2013 Jul 2;7:CD003998.
et al. Efficacy of concomitant intratympanic steroid injection for sudden deafness according to initial hearing loss. Otol Neurotol. 2015 Dec;36(10):1604–9.
F. Hereditary Hearing Loss
Sensory hearing loss with onset during adult life often runs in families. The mode of inheritance may be either autosomal dominant or recessive. The age at onset, the rate of progression of hearing loss, and the audiometric pattern (high-frequency, low-frequency, or flat) can often be predicted by studying family members. Great strides have been made in identifying the molecular genetic errors associated with hereditary hearing loss. The connexin-26 mutation, the most common cause of genetic deafness, may be tested clinically, as can most other single gene mutations known to cause hearing loss. Hearing loss is also frequently found in hereditary mitochondrial disorders. Progress is being made toward the development of methods to restore lost hair cells in genetic and other forms of deafness via gene therapy or stem cell–mediated techniques.
et al. Improving hearing loss gene testing: a systematic review of gene evidence toward more efficient next-generation sequencing-based diagnostic testing and interpretation. Genet Med. 2015 Nov 12. [Epub ahead of print]
et al. Sensorineural hearing loss: a changing paradigm for its evaluation. Otolaryngol Head Neck Surg. 2015 Nov;153(5):843–50.
G. Autoimmune Hearing Loss
Sensory hearing loss may be associated with a wide array of systemic autoimmune disorders, such as systemic lupus erythematosus, granulomatosis with polyangiitis (formerly Wegener granulomatosis), and Cogan syndrome (hearing loss, keratitis, aortitis). The loss is most often bilateral and progressive. The hearing level often fluctuates, with periods of deterioration alternating with partial or even complete remission. The tendency is for the gradual evolution of permanent hearing loss, which usually stabilizes with some remaining auditory function but occasionally proceeds to complete deafness. Vestibular dysfunction, particularly dysequilibrium and postural instability, may accompany the auditory symptoms. A syndrome resembling Ménière disease may also occur with intermittent attacks of severe vertigo.
In many cases, the autoimmune pattern of audiovestibular dysfunction presents in the absence of recognized systemic autoimmune disease. Use of laboratory tests to screen for autoimmune disease (eg, antinuclear antibody, rheumatoid factor, erythrocyte sedimentation rate) may be informative. Specific tests of immune reactivity against inner ear antigens (anticochlear antibodies, lymphocyte transformation tests) are current research tools and have limited clinical value to date. Responsiveness to oral corticosteroid treatment is helpful in making the diagnosis and constitutes first-line therapy. If stabilization of hearing becomes dependent on long-term corticosteroid use, steroid-sparing immunosuppressive regimens may become necessary.
et al. Early efficacy trial of anakinra in corticosteroid-resistant autoimmune inner ear disease. J Clin Invest. 2014 Sep 2;124(9):4115–22.
SQ. Review of experimental and clinical studies on autoimmune sensorineural hearing loss. Minerva Med. 2015 Jun;106(3):177–80.
ESSENTIALS OF DIAGNOSIS
Perception of abnormal ear or head noises.
Persistent tinnitus often, though not always, indicates the presence of sensory hearing loss.
Intermittent periods of mild, high-pitched tinnitus lasting seconds to minutes are common in normal-hearing persons.
Tinnitus is defined as the sensation of sound in the absence of an exogenous sound source. Tinnitus can accompany any form of hearing loss, and its presence provides no diagnostic value in determining the cause of a hearing loss. Approximately 15% of the general population experience some type of tinnitus, with prevalence beyond 20% in aging populations.
Though tinnitus is commonly associated with hearing loss, tinnitus severity correlates poorly with the degree of hearing loss. About one in seven tinnitus sufferers experience severe annoyance, and 4% are severely disabled. When severe and persistent, tinnitus may interfere with sleep and the ability to concentrate, resulting in considerable psychological distress.
Pulsatile tinnitus—often described by the patient as listening to one’s own heartbeat—should be distinguished from tonal tinnitus. Although often ascribed to conductive hearing loss, pulsatile tinnitus may be far more serious and may indicate a vascular abnormality, such as glomus tumor, venous sinus stenosis, carotid vaso-occlusive disease, arteriovenous malformation, or aneurysm. In contrast, a staccato “clicking” tinnitus may result from middle ear muscle spasm, sometimes associated with palatal myoclonus. The patient typically perceives a rapid series of popping noises, lasting seconds to a few minutes, accompanied by a fluttering feeling in the ear.
For routine, nonpulsatile tinnitus, audiometry should be ordered to rule out an associated hearing loss. For unilateral tinnitus, particularly associated with hearing loss in the absence of an obvious causative factor (ie, noise trauma), an MRI should be obtained to rule out a retrocochlear lesion, such as vestibular schwannoma. Magnetic resonance angiography and venography should be considered for patients who have pulsatile tinnitus to rule out a vascular lesion as causative.
The most important treatment of tinnitus is avoidance of exposure to excessive noise, ototoxic agents, and other factors that may cause cochlear damage. Masking the tinnitus with music or through amplification of normal sounds with a hearing aid may also bring some relief. Among the numerous drugs that have been tried, oral antidepressants (eg, nortriptyline at an initial dosage of 50 mg orally at bedtime) have proved to be the most effective. Habituation techniques, such as tinnitus retraining therapy, and masking techniques may prove beneficial in those with refractory symptoms. Transcranial magnetic stimulation of the central auditory system has been shown to improve symptoms in some patients. Progress is also being made toward implantable brain stimulators to treat tinnitus.
et al. A stroke of silence: tinnitus suppression following placement of a deep brain stimulation electrode with infarction in area LC. J Neurosurg. 2013 Jan;118(1):192–4.
et al. A systematic review of eligibility and outcomes in tinnitus trials: reassessment of tinnitus guideline. Otolaryngol Head Neck Surg. 2016 Jan;154(1):24–32.
Excessive sensitivity to sound may occur in normal-hearing individuals, either in association with ear disease, following noise trauma, in patients susceptible to migraines, or for psychological reasons. Patients with cochlear dysfunction commonly experience “recruitment,” an abnormal sensitivity to loud sounds despite a reduced sensitivity to softer ones. Fitting hearing aids and other amplification devices to patients with recruitment requires use of compression circuitry to avoid uncomfortable overamplification. For normal-hearing individuals with hyperacusis, use of an earplug in noisy environments may be beneficial, though attempts should be made at habituation.
et al. Decreased sound tolerance: hyperacusis, misophonia, diplacousis, and polyacousis. Handb Clin Neurol. 2015;129:375–87.
ESSENTIALS OF DIAGNOSIS
Either a sensation of motion when there is no motion or an exaggerated sense of motion in response to movement.
Duration of vertigo episodes and association with hearing loss are the key to diagnosis.
Must differentiate peripheral from central etiologies of vestibular dysfunction.
Peripheral: Onset is sudden; often associated with tinnitus and hearing loss; horizontal nystagmus may be present.
Central: Onset is gradual; no associated auditory symptoms.
Evaluation includes audiogram and electronystagmography (ENG) or videonystagmography (VNG) and MRI.
Vertigo can be caused by either a peripheral or central etiology, or both (Table 8–2).
Table 8–2.Causes of vertigo. |Favorite Table|Download (.pdf) Table 8–2. Causes of vertigo.
|Peripheral causes |
| Vestibular neuritis/labyrinthitis |
| Ménière disease |
| Benign positional vertigo |
| Ethanol intoxication |
| Inner ear barotraumas |
| Semicircular canal dehiscence |
|Central causes |
| Seizure |
| Multiple sclerosis |
| Wernicke encephalopathy |
| Chiari malformation |
| Cerebellar ataxia syndromes |
|Mixed central and peripheral causes |
| Migraine |
| Stroke and vascular insufficiency |
| Posterior inferior cerebellar artery stroke |
| Anterior inferior cerebellar artery stroke |
| Vertebral artery insufficiency |
| Vasculitides |
| Cogan syndrome |
| Susac syndrome |
| Granulomatosis with polyangiitis (formerly Wegener granulomatosis) |
| Behçet disease |
| Cerebellopontine angle tumors |
| Vestibular schwannoma |
| Meningioma |
| Infections |
| Lyme disease |
| Syphilis |
| Vascular compression |
| Hyperviscosity syndromes |
| Waldenström macroglobulinemia |
| Endocrinopathies |
| Hypothyroidism |
| Pendred syndrome |
Vertigo is the cardinal symptom of vestibular disease. While vertigo is typically experienced as a distinct “spinning” sensation, it may also present as a sense of tumbling or of falling forward or backward. It should be distinguished from imbalance, light-headedness, and syncope, all of which are nonvestibular in origin (Table 8–3).
Table 8–3.Common vestibular disorders: differential diagnosis based on classic presentations. |Favorite Table|Download (.pdf) Table 8–3. Common vestibular disorders: differential diagnosis based on classic presentations.
|Duration of Typical Vertiginous Episodes ||Auditory Symptoms Present ||Auditory Symptoms Absent |
|Seconds ||Perilymphatic fistula ||Positioning vertigo (cupulolithiasis), vertebrobasilar insufficiency, migraine-associated vertigo |
|Hours ||Endolymphatic hydrops (Ménière syndrome, syphilis) ||Migraine-associated vertigo |
|Days ||Labyrinthitis, labyrinthine concussion, autoimmune inner ear disease ||Vestibular neuronitis, migraine-associated vertigo |
|Months ||Acoustic neuroma, ototoxicity ||Multiple sclerosis, cerebellar degeneration |
1. Peripheral vestibular disease
Peripheral vestibulopathy usually causes vertigo of sudden onset, may be so severe that the patient is unable to walk or stand, and is frequently accompanied by nausea and vomiting. Tinnitus and hearing loss may be associated and provide strong support for a peripheral (ie, otologic) origin.
A thorough history will often narrow down, if not confirm the diagnosis. Critical elements of the history include the duration of the discrete vertiginous episodes (seconds, minutes to hours, or days), and associated symptoms. Triggers should also be sought, including diet (eg, high salt in the case of Ménière disease), stress, fatigue, and bright lights (eg, migraine-associated dizziness).
The physical examination of the patient with vertigo includes evaluation of the ears, eye motion in response to head turning and observation for nystagmus, cranial nerve examination, and Romberg testing. In acute peripheral lesions, nystagmus is usually horizontal with a rotatory component; the fast phase usually beats away from the diseased side. Visual fixation tends to inhibit nystagmus except in very acute peripheral lesions or with central nervous system disease. Dix-Hallpike testing (quickly lowering the patient to the supine position with the head extending over the edge and placed 30 degrees lower than the body, turned either to the left or right) will elicit a delayed onset (~10 sec) fatiguable nystagmus in cases of benign positional vertigo. Nonfatigable nystagmus in this position indicates a central etiology for the dizziness.
Since visual fixation often suppresses observed nystagmus, many of these maneuvers are performed with Frenzel goggles, which prevent visual fixation, and often bring out subtle forms of nystagmus. The Fukuda test can demonstrate vestibular asymmetry when the patient steps in place with eyes closed and consistently rotates.
In contrast to peripheral forms of vertigo, dizziness arising from central etiologies (Table 8–2) tends to develop gradually and then becomes progressively more severe and debilitating. Nystagmus is not always present but can occur in any direction and may be dissociated in the two eyes. The associated nystagmus is often nonfatigable, vertical rather than horizontal in orientation, without latency, and unsuppressed by visual fixation. ENG is useful in documenting these characteristics. The evaluation of central audiovestibular dysfunction requires imaging of the brain with MRI.
Episodic vertigo can occur in patients with diplopia from external ophthalmoplegia and is maximal when the patient looks in the direction where the separation of images is greatest. Cerebral lesions involving the temporal cortex may also produce vertigo, which is sometimes the initial symptom of a seizure. Finally, vertigo may be a feature of a number of systemic disorders and can occur as a side effect of certain anticonvulsant, antibiotic, hypnotic, analgesic, and tranquilizing drugs or of alcohol.
Laboratory investigations, such as audiologic evaluation, caloric stimulation, ENG, VNG, vestibular-evoked myogenic potentials (VEMPs), and MRI, are indicated in patients with persistent vertigo or when central nervous system disease is suspected. These studies will help distinguish between central and peripheral lesions and identify causes requiring specific therapy. ENG consists of objective recording of the nystagmus induced by head and body movements, gaze, and caloric stimulation. It is helpful in quantifying the degree of vestibular hypofunction. Computer-driven rotatory chairs and posturography platforms offer additional diagnostic modalities from specialized centers.
et al. Neural basis of new clinical vestibular tests: otolithic neural responses to sound and vibration. Clin Exp Pharmacol Physiol. 2014 May;41(5):371–80.
et al. Bedside assessment of acute dizziness and vertigo. Neurol Clin. 2015 Aug;33(3):551–64.
Vertigo Syndromes Due to Peripheral Lesions
A. Endolymphatic Hydrops (Ménière Syndrome)
The cause of Ménière syndrome is unknown. Distention of the endolymphatic compartment of the inner ear is a pathologic finding and thought to be part of the pathogenesis of the disorder. Although a precise cause of hydrops cannot be established in most cases, two known causes are syphilis and head trauma. The classic syndrome consists of episodic vertigo, with discrete vertigo spells lasting 20 minutes to several hours in association with fluctuating low-frequency sensorineural hearing loss, tinnitus (usually low-tone and “blowing” in quality), and a sensation of unilateral aural pressure (Table 8–3). These symptoms in the absence of hearing fluctuations suggest migraine-associated dizziness. Symptoms wax and wane as the endolymphatic pressure rises and falls. Caloric testing commonly reveals loss or impairment of thermally induced nystagmus on the involved side. Primary treatment involves a low-salt diet and diuretics (eg, acetazolamide). For symptomatic relief of acute vertigo attacks, oral meclizine (25 mg) or valium (5 mg) can be used. In refractory cases, patients may undergo intratympanic corticosteroid injections, endolymphatic sac decompression, or vestibular ablation, either through transtympanic gentamicin, vestibular nerve section, or surgical labyrinthectomy.
et al. Outcomes after cochlear implantation for patients with single-sided deafness, including those with recalcitrant Ménière's disease. Otol Neurotol. 2013 Dec;34(9):1681–7.
et al. Meniere’s disease: histopathology, cytochemistry, and imaging. Ann N Y Acad Sci. 2015 Apr;1343:49–57.
Patients with labyrinthitis suffer from acute onset of continuous, usually severe vertigo lasting several days to a week, accompanied by hearing loss and tinnitus. During a recovery period that lasts for several weeks, the vertigo gradually improves. Hearing may return to normal or remain permanently impaired in the involved ear. The cause of labyrinthitis is unknown. Treatment consists of antibiotics if the patient is febrile or has symptoms of a bacterial infection, and supportive care. Vestibular suppressants are useful during the acute phase of the attack (eg, diazepam or meclizine) but should be discontinued as soon as feasible to avoid long-term dysequilibrium from inadequate compensation.
et al. Recent advances in viral inner ear disorders. Curr Opin Otolaryngol Head Neck Surg. 2012 Oct;20(5):404–8.
C. Benign Paroxysmal Positioning Vertigo
Patients suffering from recurrent spells of vertigo, lasting a few minutes per spell, associated with changes in head position (often provoked by rolling over in bed), usually have benign paroxysmal positioning vertigo (BPPV). The term “positioning vertigo” is more accurate than “positional vertigo” because it is provoked by changes in head position rather than by the maintenance of a particular posture.
The typical symptoms of positioning vertigo occur in clusters that persist for several days. There is a brief (10–15 sec) latency period following a head movement before symptoms develop, and the acute vertigo subsides within 10–60 seconds, though the patient may remain imbalanced for several hours. Constant repetition of the positional change leads to habituation. Since some central nervous system disorders can mimic BPPV (eg, vertebrobasilar insufficiency), recurrent cases warrant MRI scanning of the head. In central lesions, there is no latent period, fatigability, or habituation of the symptoms and signs. Treatment of BPPV involves physical therapy protocols (eg, the Epley maneuver or Brandt-Daroff exercises), based on the theory that peripheral positioning vertigo results from free-floating otoconia within a semicircular canal.
et al. The Epley (canalith repositioning) manoeuvre for benign paroxysmal positional vertigo. Cochrane Database Syst Rev. 2014 Dec 8;12:CD003162.
et al. Clinical practice. Benign paroxysmal positional vertigo. N Engl J Med. 2014 Mar 20;370(12):1138–47.
In vestibular neuronitis, a paroxysmal, usually single attack of vertigo occurs without accompanying impairment of auditory function and will persist for several days to a week before gradually clearing. During the acute phase, examination reveals nystagmus and absent responses to caloric stimulation on one or both sides. The cause of the disorder is unclear though presumed to be viral. Treatment consists of supportive care, including oral diazepam (5 mg) or meclizine (25 mg) during the acute phases of the vertigo only, followed by vestibular therapy if the patient does not completely compensate.
The most common cause of vertigo following head injury is labyrinthine concussion. Symptoms generally diminish within several days but may linger for a month or more. Basilar skull fractures that traverse the inner ear usually result in severe vertigo lasting several days to a week and deafness in the involved ear. Chronic posttraumatic vertigo may result from cupulolithiasis. This occurs when traumatically detached statoconia (otoconia) settle on the ampulla of the posterior semicircular canal and cause an excessive degree of cupular deflection in response to head motion. Clinically, this presents as episodic positioning vertigo. Treatment consists of supportive care and vestibular suppressant medication (diazepam or meclizine) during the acute phase of the attack, and vestibular therapy.
et al. Persistent vertigo and dizziness after mild traumatic brain injury. Ann N Y Acad Sci. 2015 Apr;1343:97–105.
Leakage of perilymphatic fluid from the inner ear into the tympanic cavity via the round or oval window is a rare cause of vertigo and sensory hearing loss. Most cases result from either physical injury (eg, blunt head trauma, hand slap to ear); extreme barotrauma during airflight, scuba diving, etc; or vigorous Valsalva maneuvers (eg, during weight lifting). Treatment may require middle ear exploration and window sealing with a tissue graft; however, this is seldom indicated without a clear-cut history of a precipitating traumatic event.
et al. Perilymphatic fistulas: can we predict the diagnosis? Eur Arch Otorhinolaryngol. 2015 Aug;272(8):1885–91.
Position receptors located in the facets of the cervical spine are important physiologically in the coordination of head and eye movements. Cervical proprioceptive dysfunction is a common cause of vertigo triggered by neck movements. This disturbance often commences after neck injury, particularly hyperextension. An association also exists with degenerative cervical spine disease. Although symptoms vary, vertigo may be triggered by assuming a particular head position as opposed to moving to a new head position (the latter typical of labyrinthine dysfunction). Diagnosis may often be confused with migraine-associated vertigo, which is also associated with head movement. Management consists of neck movement exercises to the extent permitted by orthopedic considerations.
Episodic vertigo is frequently associated with a migraine type of headache. Head trauma may also be a precipitating feature. The vertigo may be temporally related to the headache and last up to several hours, although the vertigo may also occur in the absence of any headache. It may appear identical to Ménière disease but without associated hearing loss or tinnitus. Accompanying symptoms may include head pressure, visual and motion sensitivity, auditory sensitivity, and photosensitivity. Symptoms typically worsen with lack of sleep and anxiety or stress. There is often a history of motion intolerance (easily carsick as a child) and there may be a familial tendency. Food triggers may also be common, including caffeine, chocolate, and alcohol among others. Treatment includes dietary and lifestyle changes (improved sleep pattern, avoidance of stress) and antimigraine prophylactic medication.
I. Superior Semicircular Canal Dehiscence
Deficiency in the bony covering of the superior semicircular canal may be associated with vertigo triggered by loud noise exposure, straining, and an apparent conductive hearing loss. Diagnosis is with coronal high-resolution CT scan and VEMPs. Surgically sealing the dehiscent canal can improve symptoms.
et al. Radiologic classification of superior canal dehiscence: implications for surgical repair. Otol Neurotol. 2015 Jan;36(1):118–25.
et al. Evolution in surgical management of superior canal dehiscence syndrome. Curr Opin Otolaryngol Head Neck Surg. 2013 Oct;21(5):497–502.
et al. Ocular versus cervical VEMPs in the diagnosis of superior semicircular canal dehiscence syndrome. Otol Neurotol. 2013 Jan;34(1):121–6.
Vertigo Syndromes Due to Central Lesions
Central nervous system causes of vertigo include brainstem vascular disease, arteriovenous malformations, tumor of the brainstem and cerebellum, multiple sclerosis, and vertebrobasilar migraine (Table 8–2). Vertigo of central origin often becomes unremitting and disabling. The associated nystagmus is often nonfatigable, vertical rather than horizontal in orientation, without latency, and unsuppressed by visual fixation. ENG is useful in documenting these characteristics. There are commonly other signs of brainstem dysfunction (eg, cranial nerve palsies; motor, sensory, or cerebellar deficits in the limbs) or of increased intracranial pressure. Auditory function is generally spared. The underlying cause should be treated.
et al. VOR gain by head impulse video-oculography differentiates acute vestibular neuritis from stroke. Otol Neurotol. 2015 Mar;36(3):457–65.
et al. Small strokes causing severe vertigo: frequency of false-negative MRIs and nonlacunar mechanisms. Neurology. 2014 Jul 8;83(2):169–73.
DISEASES OF THE CENTRAL AUDITORY & VESTIBULAR SYSTEMS
Lesions of the eighth cranial nerve and central audiovestibular pathways produce neural hearing loss and vertigo (Table 8–3). One characteristic of neural hearing loss is deterioration of speech discrimination out of proportion to the decrease in pure tone thresholds. Another is auditory adaptation, wherein a steady tone appears to the listener to decay and eventually disappear. Auditory evoked responses are useful in distinguishing cochlear from neural losses and may give insight into the site of lesion within the central pathways.
The evaluation of central audiovestibular disorders usually requires imaging of the internal auditory canal, cerebellopontine angle, and brain with enhanced MRI.
1. Vestibular Schwannoma (Acoustic Neuroma)
Eighth cranial nerve schwannomas are among the most common intracranial tumors. Most are unilateral, but about 5% are associated with the hereditary syndrome neurofibromatosis type 2, in which bilateral eighth nerve tumors may be accompanied by meningiomas and other intracranial and spinal tumors. These benign lesions arise within the internal auditory canal and gradually grow to involve the cerebellopontine angle, eventually compressing the pons and resulting in hydrocephalus. Their typical auditory symptoms are unilateral hearing loss with a deterioration of speech discrimination exceeding that predicted by the degree of pure tone loss. Nonclassic presentations, such as sudden unilateral hearing loss, are fairly common. Any individual with a unilateral or asymmetric sensorineural hearing loss should be evaluated for an intracranial mass lesion. Vestibular dysfunction more often takes the form of continuous dysequilibrium than episodic vertigo. Other lesions of the cerebellopontine angle such as meningioma and epidermoids may have similar audiovestibular manifestations. Diagnosis is made by enhanced MRI. Treatment consists of observation, microsurgical excision, or stereotactic radiotherapy, depending on such factors as patient age, underlying health, and size of the tumor at presentation. Bevacizumab (vascular endothelial growth factor blocker) has shown promise for treatment of tumors in patients with neurofibromatosis type 2.
et al. Anti-VEGF treatment improves neurological function and augments radiation response in NF2 schwannoma model. Proc Natl Acad Sci U S A. 2015 Nov 24;112(47):14676–81.
et al. The changing face of acoustic neuroma management in the USA: Analysis of the 1998 and 2008 patient surveys from the acoustic neuroma association. Br J Neurosurg. 2014 Jan;28(1):20–4.
Vertebrobasilar insufficiency is a common cause of vertigo in the elderly. It is often triggered by changes in posture or extension of the neck. Reduced flow in the vertebrobasilar system may be demonstrated noninvasively through magnetic resonance angiography. Empiric treatment is with vasodilators and aspirin.
Vascular loops that impinge upon the brainstem root entry zone of cranial nerves have been shown to cause dysfunction. Widely recognized examples are hemifacial spasm and tic douloureux. It has been suggested that hearing loss, tinnitus, and disabling positioning vertigo may result from a vascular loop abutting the eighth cranial nerve, although this is controversial.
et al. Audiovestibular impairment presenting as a portent of vertebrobasilar infarction. Br J Hosp Med (Lond). 2014 Jan;75(1):48–9.
Patients with multiple sclerosis may suffer from episodic vertigo and chronic imbalance. Hearing loss in this disease is most commonly unilateral and of rapid onset. Spontaneous recovery may occur.
et al. Central vestibular dysfunction in an otorhinolaryngological vestibular unit: incidence and diagnostic strategy. Int Arch Otorhinolaryngol. 2014 Jul;18(3):235–8.
OTOLOGIC MANIFESTATIONS OF AIDS
The otologic manifestations of AIDS are protean. The pinna and external auditory canal may be affected by Kaposi sarcoma as well as persistent and potentially invasive fungal infections, particularly due to Aspergillus fumigatus. The most common middle ear manifestation of AIDS is serous otitis media due to eustachian tube dysfunction arising from adenoidal hypertrophy (HIV lymphadenopathy), recurrent mucosal viral infections, or an obstructing nasopharyngeal tumor (eg, lymphoma). For middle ear effusions, ventilating tubes are seldom helpful and may trigger profuse watery otorrhea. Acute otitis media is usually caused by the typical bacterial organisms that occur in the nonimmunocompromised, including Proteus, Staphylococcus, and Pseudomonas, although Pneumocystis jirovecii otitis has been reported. Sensorineural hearing loss is common and in some cases appears to result from viral central nervous system infection. In cases of progressive hearing loss, it is important to evaluate for cryptococcal meningitis and syphilis. Acute facial paralysis due to herpes zoster infection (Ramsay Hunt syndrome) is quite common and follows a clinical course similar to that in nonimmunocompromised patients. Treatment is primarily with high-dose acyclovir (see Chapters 6 and 32). Corticosteroids may also be effective.
et al. Audiologic and vestibular findings in a sample of human immunodeficiency virus type-1-infected Mexican children under highly active antiretroviral therapy. Int J Pediatr Otorhinolaryngol. 2008 Nov;72(11):1671–81.