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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4518_Библиотеки_им_академика_М_И_Перельмана
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14 Vestibular Disorders
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Surgical:
• Middle fossa canal occlusion (low recurrence rate, risk of sensorineural
hearing loss) or resurfacing (higher risk of persistent/recurrent
symptoms)
• Transmastoid occlusion avoids temporal lobe retraction; difcult access
for low-lying tegmen
• Perilymphatic stula
– Triad of hearing loss, vertigo, tinnitus
– Etiologies include iatrogenic (post-stapedectomy, most common), trauma
(temporal bone fracture, explosive or implosive barotrauma), congenital/
spontaneous (controversial), and erosive (cholesteatoma, otosyphilis).
– Clinical: sudden or progressive sensorineural hearing loss/vertigo/tinnitus,
may uctuate; may be associated with a positive Hennebert’s sign, Tullio’s
phenomenon, or stula test.
– Diagnosis: no denitive diagnostic criteria, must be conrmed via middle ear
exploration; CT may show pneumolabyrinth or middle ear anomalies; protein
markers have been suggested (beta-2 transferrin, beta-trace protein).
– Treatment:
Conservative: bed rest, head elevation, avoidance of straining, and stool
softeners.
Surgical: may be performed from the outset or in cases where progressive
hearing loss and persistent vertigo develop following initial period of
observation.
Middle ear exploration with plugging of affected site.
Plugging of oval and round windows has been suggested even if no stula
is observed, but this may cause conductive hearing loss.
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• Other etiologies of peripheral vestibular disorders
– Autoimmune:
Cogan’s syndrome: episodic vertigo lasting hours (similar to Meniere’s
disease), sensorineural hearing loss, non-syphilitic interstitial keratitis; steroid responsive
Vogt-Koyanagi-Harada Syndrome: hearing loss, vertigo, uveitis, vitiligo,
steroid responsive
Autoimmune inner ear disease: see below
– Otosyphilis: episodic vertigo and sensorineural hearing loss, can mimic
Ménière’s disease, perilymphatic stula, autoimmune inner ear disease; classically with positive Hennebert’s sign and positive Tullio’s phenomenon; consider FTA-ABS in high-risk patients with vertigo.
– Inner ear decompression sickness (Caisson disease, “the bends”): vertigo,
hearing loss, tinnitus seen in divers during ascent (nitrogen becomes more
soluble in inner ear during descent because of increased pressure, on ascent
solubility decreases and air bubbles form); treatment is hyperbaric oxygen.
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– Medication ototoxicity:
Aminoglycosides: gentamicin and streptomycin more vestibulotoxic;
kanamycin and amikacin more cochleotoxic.
12S rRNA mutation increases susceptibility to aminoglycoside ototoxicity.
Vancomycin, Lasix, cisplatin, and Flagyl all potentiate aminoglycoside
toxicity.
Clinical: oscillopsia, ataxia
Diagnosis: rotary chair is the most sensitive test for bilateral weakness
(decreased gain, increased phase lead), may also have bilateral caloric
weakness on electronystagmography.
Can monitor for inner ear damage while using ototoxic medications using
otoacoustic emissions and audiometry.
• Etiologies of central vestibular disorders
– Migraine: most common, variable duration of vertigo/disequilibrium
– Infarction/ischemia: Vertebrobasilar insufciency, Wallenberg syndrome
– Multiple sclerosis
– Cerebellar ataxia syndromes
– Neoplasms affecting brainstem/cerebellum
– Craniovertebral junction disorders: can result in compression of basilar artery
(basilar impression), cerebellum (Chiari malformation), vertebral artery
(atlantoaxial dislocation)
– Vascular loop compression syndrome: controversial cause of repeated brief
spells of vertigo, thought to be caused by irritability of the vestibular nerve
from a vascular loop
– Persistent perceptual postural dizziness: nonspecic dizziness/imbalance
complaints with intolerance of complicated visual stimuli, high association
with anxiety, normal diagnostic evaluation, may respond to SSRIs
S. Pelosi
• Vestibular migraine
– Variety of dizziness/disequilibrium symptoms associated with migraine
headaches.
– Episodic vertigo occurs in 25–35% of migraine patients; most common in
women; may also experience chronic disequilibrium.
– Patients may have personal or family history of migraine.
– Clinical:
Vestibular: episodic vertigo, constant imbalance, movement-associated
disequilibrium, light-headedness
Headache may occur before, during, or not at all; may have photophobia,
phonophobia, and visual aura
Motion intolerance, sensitivity to complex visual stimuli
Hearing loss uncommon, may have unilateral or bilateral tinnitus
14 Vestibular Disorders
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– Subtypes:
Basilar migraine: more clearly dened subtype of migraine with aura;
patients have two or more symptoms (vertigo, tinnitus, hearing loss, ataxia,
dysarthria, visual symptoms, diplopia, paresthesia, paresis, decreased consciousness) followed by a throbbing headache.
Benign positioning vertigo of childhood: episodic vertigo in children lasting minutes to hours, may progress to migraine, strong migraine family
history.
– Diagnosis: electronystagmography normal; MRI may show nonspecic white
matter lesions.
– Treatment:
Prophylactic: nortriptyline, verapamil, topiramate.
Diet: avoid migraine triggers (MSG, alcohol, aged cheese, chocolate,
aspartame).
Vestibular rehabilitation may aggravate symptoms.
• Infarction/ischemia
– Vertebrobasilar insufciency: transient ischemic attacks in brainstem vascula-
ture associated with atherosclerosis; may experience transient vertigo; can
also have diplopia, dysphagia, and drop attacks.
– Wallenberg syndrome: posterior inferior cerebellar artery (PICA) thrombosis
causing lateral medullary infarction—symptoms include acute vertigo, ataxia,
ipsilateral Horner syndrome, ipsilateral palatal paresis and vocal ford paraly-
sis, ipsilateral face numbness, and contralateral decreased pain sensation
from body.
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• Multiple sclerosis
– Demyelinating central nervous system disorder affecting multiple white mat-
ter regions
– Dizziness is a common symptom; may have other neurologic symptoms
caused by scattered plaques in different brain regions (spasticity, unilateral
sensory disturbances, optic neuritis)
– Electronystagmography: disconjugate eye movements (internuclear ophthal-
moplegia), ocular dysmetria on saccade testing (undershoot, overshoot),
impaired smooth pursuit
– Diagnosis: Labs, increased gamma globulin/oligoclonal bands; MRI, scat-
tered white matter plaques
• Cerebellar ataxia syndromes
– Wide range of disorders which collectively cause inability to coordinate bal-
ance, gait, extremity, and eye movements.
– Some conditions include cerebellar atrophy, ataxia telangiectasia, Friedrich’s
ataxia, Refsum’s disease, paraneoplastic cerebellar degeneration, and familial
episodic ataxia.
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S. Pelosi
– Clinical:
– Symptoms: difculty with ne motor control (writing, eating), walking with
wide stance, may affect speech and swallowing
– Exam: dysmetria, dysdiadochokinesia, dysarthria
– Electronystagmography: abnormalities of oculomotor testing—ocular dys-
metria on saccade testing (undershoot, overshoot), abnormal smooth pursuit,
direction-changing nystagmus or periodic alternating nystagmus (changes
direction every 2–6min), rebound nystagmus (gaze-evoked nystagmus that
fatigues and changes direction after a few seconds)
– Treatment involves management of underlying cause.
• Craniovertebral junction disorders
– Can result in compression of basilar artery (basilar impression), cerebellum
(Chiari malformation), and vertebral artery (atlantoaxial dislocation)
– Classically shows vertical down-beating nystagmus, more prominent with
down gaze or lateral gaze
Further reading
1. Bhattacharyya N, Gubbels SP, Schwartz SR, etal. Clinical practice guideline: benign paroxysmal positional vertigo (update). Otolaryngol Head Neck Surg. 2017;156(3S):S1–47.
2. American Academy of Otolaryngology-Head and Neck Foundation, Inc. Committee on
Hearing and Equilibrium guidelines for the diagnosis and evaluation of therapy in Meniere’s
disease. Otolaryngol Head Neck Surg. 1995;113:181–5.
3. Schwarz-Dietrich W, Tomlinson RD.Physiology of the vestibular system. In: Jackler RKBD,
editor. Neurotology. Maryland Heights: Mosby; 2004. p.91–121.
4. Valente M, Fernandez E, Monroe H.Vestibular evaluation. In: Valente M, Fernandez E, Monroe
H, editors. Audiology answers for otolaryngologists. NewYork: Thieme; 2010.
5. Crowson MG, Patki A, Tucci DL.A systematic review of diuretics in the medical management
of Meniere’s disease. Otolaryngol Head Neck Surg. 2016;154(5):824–34.
6. Wu IC, Minor LB.Long-term hearing outcome in patients receiving intratympanic gentamicin
for Meniere’s disease. Laryngoscope. 2003;113:815–20.
7. Minor LB, Solomon D, Zinreich JS, Zee DS. Sound- and/or pressure-induced vertigo due
to bone dehiscence of the superior semicircular canal. Arch Otolaryngol Head Neck Surg.
1998;124:249–58.
8. Lempert T, Olesen J, Furman J, etal. Vestibular migraine: diagnostic criteria. J Vestib Res.
2012;22:167–72.
Chapter 15
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Otologic Disorders
StanleyPelosi
Pearls
• Sudden sensorineural hearing loss is classied as unilateral hearing loss of at
least 30dB in at least three frequencies occurring within 3 days.
• Otosclerosis is an autosomal dominant metabolic bone disease of the otic capsule and ossicles that causes stapes xation, most commonly at the ssula ante
fenestram.
• Acute coalescent mastoiditis is the most common intratemporal complication of
otitis media.
Sensorineural Hearing Loss
• Congenital
– Hereditary (50%)
Syndromic (30%): most common causes include Usher and Pendred syndromes (both autosomal recessive).
Non-syndromic (70%) GJ2B mutation (autosomal recessive) codes for the
protein gap junction beta-2 (also called connexin 26); results in impaired
K+ exchange.
S. Pelosi (*)
Long Island Jewish Medical Center, Donald and Barbara Zucker School of Medicine at
Hofstra/Northwell, New Hyde Park, NY, USA
© Springer Nature Switzerland AG 2023
F. Y. Lin, Z. M. Patel (eds.), ENT Board Prep,
https://doi.org/10.1007/978-3-031-26048-3_15
295
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– Nonhereditary (25%)
Infectious: Cytomegalovirus (most common cause of congenital viral
deafness), mumps (most common cause of acquired sensorineural hearing
loss), rubella
Other perinatal factors: prematurity, maternal diabetes,
hyperbilirubinemia
– Idiopathic (25%)
• Acquired
– Presbycusis (most common): progressive symmetric sensorineural hearing
loss associated with aging, begins in high frequencies, manage with hearing
aids, cochlear implant if severe-profound.
– Noise-induced hearing loss: often associated with a 4-kHz notch.
– Post-meningitis: associated with labyrinthitis ossicans which can prevent
cochlear implantation.
– Cerebrovascular accident.
– Ototoxic medication exposure.
– Autoimmune inner ear disease: subtypes include Cogan’s syndrome, relaps-
ing polychondritis, Wegener’s granulomatosis, systemic lupus erythematosus,
Sjogren’s syndrome, and rheumatoid arthritis.
– Idiopathic, including sudden sensorineural hearing loss.
– Vestibular schwannoma or meningioma: usually asymmetric and displays ret-
rocochlear pattern (disproportionately poor word recognition compared to
pure tone losses).
– Erosive inner ear disease (cholesteatoma, chronic otitis media without
cholesteatoma).
– Noise-induced hearing loss:
S. Pelosi
Temporary threshold shift: brief period of hearing loss after noise exposure
that returns to normal after rest.
Permanent threshold shift: hearing loss that does not return to previous
hearing level.
Natural resonance of external auditory canal is 3kHz (may be the reason
for a “noise notch” at 4kHz).
Workplace restrictions based on recommendations from Occupational
Safety and Health Administration (OSHA):
• Must limit noise exposure at 90dB to 8h; with each 5dB increase must
cut exposure into half.
• Employers must provide protective hearing equipment for 8 h timeweighted average over 90dB.
• Hearing conservation program must be implemented for average exposure 85dB or greater over 8h.
15 Otologic Disorders
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• Sudden sensorineural hearing loss
– Unilateral hearing loss of at least 30dB in at least three frequencies occurring
within 3 days
– Unknown etiology, possible viral or vascular (ischemic) cause
– Studies: audiogram, MRI to rule out vestibular schwannoma (incidence in
general population 2/100,000, but as high as 2–10% in sudden sensorineural
hearing loss patients)
– Treatment
Oral prednisone typically given at 1mg/kg/day (up to 60mg) for 7–14
days; then taper; contraindicated in diabetics
Intratympanic dexamethasone
• Give 10, 24, or 40mg/mL every 3–7 days for up to 3–4 doses
• Can be given as adjunct to oral steroids or alone if oral steroid
contraindication
Hyperbaric oxygen: may reduce inammation and promote healing of hair
cells, more popular abroad
Antivirals: have been used historically
AAO-HNS clinical practice guidelines (CPG)
• Recommend: oral or intratympanic steroids as rst line
• Option: hyperbaric oxygen in rst 3 months
• Recommend against: antivirals
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Prognosis worse with greater degree of hearing loss, hearing loss that presents with vertigo, advanced age
• Auditory neuropathy/dyssynchrony
– Dened as abnormal/absent auditory brainstem response but evidence of
inner hair cell function (cochlear microphonic and otoacoustic emissions normal)
– Thought to be caused by abnormal central auditory temporal processing in
response to stimulus
– Typically seen in young children, frequent association with other develop-
mental delays
– May have relatively good pure tone thresholds but poor speech understanding
and auditory development
– Exhibit variable response to amplication and/or cochlear implants
• Autoimmune inner ear disease (AIED)
– Subacute progressive bilateral sensorineural hearing loss that responds to ste-
roids (too slow to be sudden sensorineural hearing loss, too fast to be
presbycusis)
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– Diagnostic criteria
Bilateral sensorineural hearing loss >30dB at any frequency
Progression in at least one ear on two serial audiograms <3 months apart
15% with other systemic autoimmune disease including multiple sclerosis,
rheumatoid arthritis, and inammatory bowel disease
– Studies
Audiogram, MRI internal auditory canal if asymmetric hearing.
Labs: may consider anti-HSP-70 (= 68-kD antigen), limited sensitivity/
specicity.
If other autoimmune disease is suspected (arthritis, ocular disease, skin
lesions, kidney disease), order erythrocyte sedimentation rate, antinuclear
antibody, and rheumatoid factor.
– Treatment
Trial of prednisone 60mg daily for 4 weeks.
Non-steroid responders taper immediately.
Steroid responders may require maintenance doses for months.
Methotrexate an option for long-term maintenance; but large RCT showed
lack of effectiveness.
Immunomodulators: Anakinra (IL-1 receptor antagonist) with demonstrated efcacy in phase 1 trial.
S. Pelosi
• Hearing aids
– Amplify sound based on the degree of hearing loss at a given frequency
– Hearing aid terminology
Gain: ratio of output to input
Occlusion effect: larger hearing aids block external auditory canal which
results in low-frequency amplication
Compression: adjusts the range of sound to t the patient; often includes
making quiet sounds louder and making very loud sounds quieter
Venting: allows low-frequency sounds to escape, decreases occlusion
effect but can increase feedback
Feedback: sound coming out of speaker travels back to microphone and is
amplied again, worse with venting and smaller aids since less distance
between microphone and speaker
– Smaller hearing aids afford better cosmesis, decreased occlusion effect, lim-
ited gain due to feedback problems, can malfunction from moisture/cerumen
In-the-ear
In-the-canal
Completely-in-the-canal
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– Larger hearing aids provide better gain/amplication, longer battery life,
decreased feedback, risk of occlusion effect
Behind-the-ear
Open-t: behind the ear aid connected by thin tube to a non-occluding
earmold; decreases occlusion effect
– Digital hearing aids: better programming exibility, can amplify specic fre-
quencies while reducing gain of background noise, more expensive than analog hearing aids
– Binaural hearing aid advantages: better sound localization, better hearing
in noise
– Bone anchored hearing aid (BAHA): indicated for (1) patients with conduc-
tive hearing loss and inability to wear hearing aids (external/middle ear malformations, chronic otorrhea/dermatitis) and (2) patients with unilateral
sensorineural hearing loss
– Contralateral routing of signal (CROS): microphone on deaf side routed to
good side; Bi-CROS: microphone on deaf side routed to better hearing ear,
which is then amplied with a hearing aid
• Cochlear implants
– Convert sound into an electrical signal to stimulate cochlear nerve directly
– Components: microphone collects sound→speech processor analyzes sound
and separates into different channels based on frequency/intensity→external
transmitter→internal receiver/stimulator→electrode array
– Candidacy criteria
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Candidacy criteria varies slightly depending on patient age, implant manufacturer, and insurance type.
General criteria for adults: bilateral pure tone average worse than 70dB
and bilateral aided speech discrimination scores no better than 60%.
For Medicare patients, speech discrimination should be less than 40%
bilaterally.
Med-El implants recently approved for single-sided deafness in ages 5–12.
Children should have profound hearing loss (assessed via otoacoustic
emissions, auditory brainstem response) and failure of auditory skills
development, with minimal to no benet from hearing aids; being
implanted as young as 1 year of age.
– Contraindications
Cochlear ossication (post-meningitis); MRI more sensitive than CT for
detecting labyrinthitis ossicans (shows absent inner ear uid on
T2 images)
Absent cochlear nerve suggested by narrow internal auditory canal on CT,
can conrm presence/absence of cochlear nerve on MRI)
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– Surgical approach
Mastoidectomy with facial recess and cochleostomy or round window
opening with electrode insertion.
Contracted mastoid cavities or chronic ear disease may require canal wall
down mastoidectomy and mastoid obliteration.
– Best outcomes with shorter duration of deafness (most important predictor),
longer duration of implant use, increased level of residual hearing prior to
implantation, post-lingual patients
– Complications
Device exposure/extrusion
Device failure (hard failure, can be detected with testing of device integrity
by audiologist; soft failure, device testing normal but decrease in patient’s
cochlear implant performance over time).
Wound infection.
Meningitis: increased risk of pneumococcal meningitis in all cochlear
implant recipients; both adult and pediatric patients require
immunization.
Facial paralysis and dysgeusia (<1%).
Facial stimulation: more common in patients with inner ear otosclerosis.
Perilymphatic gusher: increased risk in patients with congenital inner ear
deformities; persistent leakage can increase meningitis risk; manage by
limiting cochleostomy size, plugging with muscle.
S. Pelosi
Conductive Hearing Loss
• Otosclerosis
– Metabolic bone disease of otic capsule and ossicles that causes stapes xation.
– Autosomal dominant with incomplete penetrance.
– 10% prevalence in Caucasians, 1% with clinical disease.
– Most common site is ssula ante fenestram; other subtypes→bipolar (ante-
rior/posterior involvement only), biscuit (footplate only), obliterative (footplate+annular ligament).
– Clinical:
Progressive conductive hearing loss beginning in 20s to 30s, + tinnitus,
typically without a history of chronic otitis media or prior ear surgery.
Patients may have autophony, Paracusis of Willis: improved hearing in
background noise—speaker is talking with increased volume to compensate for background noise (increased signal), and patient’s conductive
hearing loss causes decreased perception of background noise
(decreased noise).
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