SNHL Saisuree Nivatwongs ENT-PMK. Sensorineural hearing loss Introduction History Physical examination Auditory testing Vestibular testing Laboratory

SNHL

Saisuree Nivatwongs

ENT-PMK

Sensorineural hearing loss

Introduction

• History• Physical examination• Auditory testing• Vestibular testing• Laboratory testing• Radiographic testing

Sensorineural hearing loss

Etiology

• Development & Hereditary disorder• Infectious disorder• Pharmacologic disorder• Trauma• Neurologic disorder• Vascular & Hematologic disorder

• Immune disorder• Bone disorder• Neoplasms• Endocrine &

Metabolic disorder• Disorder of

unknown etiology

**Sudden Sensorineural hearing loss**

History

• Unilateral / Bilateral• Chronicity• Tinnitus / Vertigo• Otalgia / Otorrhea• Headache• Eye symptoms

• Underlying disease

• Ototoxic drugs• Hx of trauma• Noise exposure• Family Hx

Physical Examination

• Weber / Rinne test• Otoscopy• Cranial nerve• Stigmata of associated disease• Generally no abnormality**

Auditory Testing

• Conventional audiometry

• Tympanometry• Acoustic reflex

threshold• Auditory brainstem

response• Electrocochleography• Otoacoustic emission

Clinical evaluation

Laboratory testing• Fluorescent treponemal

antibody absorption test : FTA-ABS

• Microhemagglutination test for Treponema pallidum : MHA-TP

• Venereal disease research laboratory : VDRL

• Routine hematologic studies

• Routine metabolic studies

Vestibular testing• Adjunct in selected patients

Radiographic testing• MRI with Gadolinium

Retrocochlear hearing loss?• Computed tomography

Labyrinthine abnormality?

Etiology

• Development & Hereditary disorder• Infectious disorder• Pharmacologic disorder• Trauma• Neurologic disorder• Vascular & Hematologic disorder• Immune disorder• Bone disorder• Neoplasms• Disorder of unknown etiology

Development & Hereditary disorder

• Waardenburg syndrome• Large vestibular aqueduct syndrome• Usher syndrome• Alport syndrome

Etiology


Infectious disorder

LabyrinthitisSerous labyrinthitis

• Abnormal process within the labyrinth

• Endolymphatic hydrops• Hearing loss and vestibular

dysfunction • Permanent or transient• Sudden onset of

sensorineural hearing loss and acute vertigo

• Viral labyrinthitis is common

Suppurative labyrinthitis • Bacterial invasion of the

inner ear• Profound hearing loss and

acute vertigo • Caused by a fistula between

the middle ear and the labyrinth

• Alternatively, the route of invasion can be meningogenic

• Most common etiology of deafness associated with meningitis

Infectious disorder

Herpes zoster oticus

• Varicella-zoster infection• Most commonly associated

with facial paralysis • HL and vertigo can occur

Infectious disorder

Measles• Not uncommon cause

of deafness in children

• Bilateral HL• Moderate-to-profound

HL• Vestibular function

can be similarly affected

Mumps• Paramyxovirus

infection • Unilateral SNHL • Unilateral deafness in

otherwise healthy children

• Sudden deafness in adult Subclinical mumps infection in those without previous immunity

Infectious disorder

Cytomegalovirus

• Common cause of congenital and progressive HL in children

• Sudden SNHL in adults • Hearing loss

associated with AIDS may represent reactivation of latent CMV infections

Infectious disorder

Syphilis

• Congenital or acquired syphilis • 80% Symptomatic neurosyphilis• HL in syphilis Meningolabyrinthitis • Syphilitic HL Indistinguishable

from Ménière’s disease• Hennebert’s sign (a positive fistula

test without middle ear disease) • Tullio’s phenomenon (vertigo or

nystagmus on exposure to high-intensity sound)

Etiology


Pharmacologic disorder

Aminoglycosides Streptomycin, Kanamycin,

Neomycin, Amikacin, Gentamicin, Tobramycin, and Netilmycin

Death of the hair cell Different patterns of ototoxicity

with different aminoglycosides Unilateral or asymmetric Reversibility of the HL Risk factors

(1) presence of renal disease (2) longer duration of therapy (3) increased serum levels

(4) advanced age (5) concomitant administration

of other ototoxic drugs

Ototopical preparations

Neomycin, Gentamicin, and Tobramycin-containing

Cochlear or vestibular ototoxicity

Avoid the use of aminoglycoside-containing topical preparations in uninflamed ears with tympanic membrane perforations

Ingredients of ototopical preparations also have ototoxic potential

Polymyxin B, Propylene glycol, Acetic acid, Antifungal agents


Loop diuretics Effect by blocking sodium

and water reabsorption in the proximal loop of Henle

Reversible SNHL Bilateral and symmetric Sudden in onset Alteration of

endolymphatic ion concentration and endocochlear potential

Risk factors (1) Renal failure (2) Rapid infusion (3) Aminoglycoside

administration

Antimalarials

Quinine Tinnitus, SNHL, & Visual disturbances

Chincinonism Tinnitus, headache, nausea, and disturbed vision

Quinine appears to be primarily on hearing and usually is transient

Permanent hearing loss may occur with large doses or in sensitive patients


Salicylates Aspirin Tinnitus and

reversible SNHL HL Dose-dependent Moderate-to-severe

range SNHL, loss of otoacoustic

emissions, reduced cochlear action potentials

Alteration of the “tips” of auditory nerve fiber tuning curves

Alteration in turgidity and motility of outer hair cells

Nonsteroidal antiinflammatory

drugs Naproxen, Ketoralac &

Piroxicam Ototoxicity resulting from

use of NSAIDs is rare Only reversible physiologic

changes, without major morphologic changes


Vancomycin Almost received

Vancomycin & loop diuretics or aminoglycosides

Ototoxicity Intravenously Permanent or transient

SNHL Excreted by the kidney Renal failure

Vancomycin half-life Increase ototoxicity

Itself ototoxic Unclear

Erythromycin Uncommon Partially Intravenously Reversible on

discontinuation No reports

- Newer macrolide - Clarithromycin

- Azithromycin


Nitrogen mustards Antineoplastic agents Mechlorethamine has

Serious ototoxicity Limited use Severe

toxic Shrinkage of the organ of

Corti Loss of inner and outer

hair cells

Cisplatinum Cell-cycle nonspecific

cancer chemotherapeutic agent

Dose-limiting SNHL Adults (25% to 86%) Children (84% to 100%) Bilateral / Irreversible Tinnitus or vertigo HL Dose-related Progressive outer hair

cell loss Inner hair cells, neural

structures and the stria vascularis are affected


Vincristine and vinblastine

The vinca alkaloids Potent neurotoxicity Peripheral neuropathy Cranial neuropathies,

ataxia, and hearing loss

Loss of hair cells and primary auditory neurons

Eflornithine Drug treatment of

trypanosomiasis Some

Pneumocystis carinii pneumonia, Cryptosporidiosis, Leishmaniasis, and Malaria

Cause major and dose-related SNHL


Deferoxamine Iron-chelating agent Auditory and visual

neurotoxicity Particularly with

larger doses in younger patients

The SNHL is reversible in some patients when the dosage is reduced

Lipid-lowering drugs

Wallerian-like degeneration

High doses of HMG-CoA reductase inhibitors

Optic& vestibulocochlear nerve degeneration

No clinically significant effect on vision or hearing

Etiology


Trauma

Head injury Blunt head injury alone

Concussive injury of the labyrinth

Labyrinthine injury SNHL

Temporal bone fracture Labyrinthine concussion

Longitudinal fractures Similar to acoustic trauma

Limited to the high F Worse at 4 kilohertz

Transverse fractures Complete loss of auditory & vestibular function

Penetrating injuries Subluxation ofthe

stapes into the vestibule Profound SNHL

Trauma

Noise-induced HL & Acoustic trauma

First published in the 1930s

Common occupationally-induced disabilities

Common in industry Caused by excessive

noise exposure Temporary SNHL that

recovers over the next 24 to 48 hours

High intensity & repeated Permanent

Outer hair cell Most effect

More damage in - High-frequency sound - Continuous sound - Pure tones

Symmetric & Bilateral HL Limited to 3 kHz, 4 kHz,

and 6 kHz Greatest loss 4 kHz Progress rapidly in first

10 to 15 years of exposure

Trauma

Noise-induced HL & Acoustic trauma

Common patterns Flat & downsloping losses

Acoustic trauma Unilateral or asymmetric

OSHA does not allow unprotected exposures greater than 90 dBA based on an 8 hour/day time weighted average (TWA)

Variability Age, gender, race, and coexisting vascular disease

No known way to predict susceptibility to NIHL

Protection Earplugs or earmuffs

Many hazardous noise exposures are not occupational in origin

Trauma

Barotrauma Unequalized pressure

differentials between the middle and external ears

Occurs during flying or underwater diving

Pain, hyperemia and possible perforation of the tympanic membrane

Edema and ecchymosis of the middle ear mucosa

Conductive HL may result

Perilymphatic fistula Pathologic communication

between the perilymphatic space of the inner ear and the middle ear

Congenital or acquired Occur at either the round

or oval windows

Perilymphatic fistula

Congenital Occur in the stapes

footplate with labyrinthine anomalies

Such as Mondini dysplasia

Communicate with the subarachnoid space and result in cerebrospinal fluid leak and possible meningitis

Profound hearing loss

Acquired Result of

- Barotrauma - Direct trauma of temporal - Indirect trauma of temporal - Complication of stapedectomy

Sudden SNHL and vertigo after a head injury, barotrauma, or heavy lifting or straining

May be spontaneously Diagnosis

Middle ear exploration

Trauma

Irradiation

Conventional fractionated irradiation of the temporal bone

Fractionated irradiation Limited extent to treat vestibular schwannoma

Difficult to determine because of the limited data available

Stereotactic irradiation (“radiosurgery”) for vestibular schwannoma

This modality Risk of SNHL High as with microsurgical removal

Etiology


Neurologic disorders

Multiple sclerosis Multiple areas of CNS

demyelination, inflammation, and glial scarring

Age 20 to 30 years More common in women Cause Unknown 4% to 10% of MS SNHL Progressive or sudden Bilateral, unilateral,

symmetric, or asymmetric Speech discrimination

Normal or reduced

Abnormalities of the ABR MRI Periventricular

white-matter plaques on T2-weighted images

Neurologic disorders

Benign intracranial hypertension

Pseudotumor cerebri Increased intracranial

pressure Without evidence of mass

lesion, obstructive hydrocephalus, intracranial infection, or hypertensive encephalopathy

Headache and visual blurring Pulsatile tinnitus SNHL and vertigo More in young, obese women

SNHL Fluctuating, low-F Unilateral or bilateral Vertigo and aural fullness Diagnosis

Papilledema CSF pressure > 200 mmH2O ABR abnormalities

Management - Weight loss- Acetazolamide- Furosemide- Lumbar-peritoneal shunting

Etiology


Vascular and hematologic disorders

Migraine• Headache and visual aura• Basilar migraine

Vertigo, SNHL Tinnitus, aural fullness Distortion & recruitment

• 46% Bilateral, low-F-SNHL

• Fluctuated HL • Similarity, between basilar

migraine and Ménière’s Dz.• Drugs in basilar migraine

No systematic study

Vertebrobasilar arterial occlusion

• Brainstem syndromes• Anterior inferior cerebellar

artery (AICA) • Occlusion of AICA SNHL• Thrombosis or embolism • Area infarcted Inferior pons• Acute AICA infarction• Acute vertigo with N/V• Facial paralysis, SNHL• Tinnitus, gaze paralysis• Loss of pain and temperature

sensation on the face• Ipsilateral Horner’s syndrome


Waldenström’s macroglobulinemia

• Abnormally large amounts of IgM in the plasma

• Increased blood viscosity • Subsequent ischemic lesions• Progressive & sudden SNHL• SNHL responded to

alkylating agents or plasmapheresis


Sickle cell anemia• Incidence of SNHL• ~ 22% of sickle cell

disease• Progressive or sudden• Associated with sickle

cell crises


Leukemias & Lymphomas

• SNHL Leukemic infiltrates Inner ear hemorrhage Vascular occlusion Labyrinthine ischemia

Etiology


Immune disorders

Cogan’s syndromeo Attacks of acute non-

syphilitic interstitial keratitis

o Auditory and vestibular dysfunction

o Unilateral or bilateral SNHL

o Severe vertigo, nausea, vomiting, and tinnitus

o Progresses to a profound loss over months

o Ophthalmologic findings o If treated SNHL is

responsiveo Aggressive treatment with

steroids

Immune disorders

Polyarteritis nodosa

o Necrotizing vasculitis of small- and medium-sized arteries

o Myriad of findings, including weight loss, fatigue, fever, anorexia, arthritis, neuropathy, hypertension, renal failure, abdominal pain, and SNHL

o Biopsy Necrotizing vasculitiso Unilateral or bilateral o Facial paralysis also may be seeno Management

- Aggressive doses of steroids - Immunosuppressive drugs

Immune disorders

Relapsing polychondritis

o An inflammatory reaction in multiple cartilages

o The auricles 1st affectedo Arthritis and eye findings o HL Conductive

Sensorineural Mixed HL

o SNHL Sudden or progressive

o May be associated with vestibular disturbances

o Rx Steroids Immunosuppresive Dapsone

Immune disorders

Wegener’s granulomatosis

o Necrotizing granulomatous vasculitis involving principally the lungs, airway, and kidneys

o Usually Conductive HLo CHL Involvement of the

eustachian tube or middle ear

o SNHL If extends into the inner ear

Immune disorders

Primary autoimmune

inner ear disease

o McCabe Bilateral SNHL responsive to immunosuppressive drugs

o Sudden or progressive HLo Involves both earso Associated with vestibular

symptoms o Strongly mimic Ménière’s

disease

o Humoral autoimmunity Abnormal

o Responsiveness of the HL to steroids or cytotoxic drugs The hallmark

o Used Methotrexate Reduce the need for continued high-dose steroids

Etiology


Bone disorders

Otosclerosis Primarily causes

CHL Uncommonly

Progressive SNHL Especially in late

disease CT images

Radiolucent area surrounding the cochlea

Advanced otosclerosis Bilateral profound mixed hearing loss

Bone disorders

Paget’s disease Osteitis deformans Most common in older ~ 50% of Paget’s disease

Conductive, SNHL or mixed

Rarely fixed stapes footplate RX

Calcitonin Eidronate disodium

Etiology


Neoplasms

Vestibular schwannoma

Most common neoplasm SNHL

Originate from 8th CN Within the CPA or the IAC Approximately 80% of all

CPA neoplasms Progressive unilateral SNHL Principally the high

frequencies

Neoplasms

Vestibular schwannoma Speech discrimination is

reduced out of proportion to the pure tone thresholds

Sudden SNHL 10% of patient

Unilateral or asymmetric tinnitus

With or without hearing loss Mild or severe vestibular

symptoms or may have none

Disorders of unknown etiology

Presbycusis Aging process Without other apparent

etiology Age-related change

Stiffness of the basilar membrane

30% of aged > 65 years Worse for high

frequencies More severe in men

Schuknecht 4 types

Presbycusis

Neural presbycusis - Loss of auditory nerve fibers

- Reduced speech discrimination out of proportion to their pure tone thresholds

Cochlear presbycusis - Mechanical CHL

Sensory presbycusis - Progressively hair cells loss - Steeply sloping HF-SNHL

Strial presbycusis - Atrophy of the stria vascularis - Flat audiograms


Ménière’s disease

Fluctuant SNHL Tinnitus, episodic vertigo,

and aural fullness Progresses, gradually or

quickly HL Tinnitus “Buzzing” or

“Roaring” Aural fullness Typically

fluctuates

Vertigo Several hours After attacks Fatigued

for 24 hours or more Profound loss is rare Low F Commonly Bilateral in 30% to 50% Endolymphatic spaces

dilatation of the inner ear


Ménière’s disease Vestibular destructive

therapy No effective No therapy Effective in

HL Medical therapy

- Sodium-restricted diet - Diuretic administration

Lack of an objective diagnostic test

Idiopathic endolymphatic hydrops

Other pathologic endolymphatic hydrops processes - Syphilis - Temporal bone trauma - Serous labyrinthitis - Stapedectomy - Autoimmune disease

Thank you for your attention

Documents

SNHL Saisuree Nivatwongs ENT-PMK. Sensorineural hearing loss Introduction History Physical examination Auditory testing Vestibular testing Laboratory