Download Clinical Evaluation Of The Patient With Hearing loss

SNHL
Diagnosis and Treatment
Dr Mandana Amiri
Otolaryngologist
KUMS
Why is hearing very important?
 Means to recognize the world
 Foundation to develop speech
 Affection sharing, life enjoying
 Important means of communication
Level of Hearing loss
Level
dB HL
Normal
≤25dBHL
Mild
26～40dBHL
Moderate
41～70dBHL
Severe
71～90dBHL
Profound
﹥90dBHL
Ear Anatomy
It’s a Miracle
How We Hear
Semi Circular Canals
Ossicles
Nerve
Ear Drum
Cochlea
Developed by HLA-Wake County, Raleigh, NC
Mechanism of Hearing
Mechanism of Hearing
Mechanism of Hearing
Sensorineural Hearing Loss
Clinical Evaluation Of The Patient With Hearing loss
1) History
2) Physical Examination
3) Audiometric Testing: Audiometry
ABR
ECG
OAE
4) Vestibular Testing
5) Laboratory Testing
6) Radiologic Testing
Etiology Of SNHL
1) Developmental And hereditary
2) Infectious disorder
3) Pharmacologic Toxicity
4) Renal disorders
5) Trauma
6) Irradiation
7) Neurologic Disorders & Neoplaasms
8) Vascular and Hematologic
9) Immune disorder
10) Bone disorder
11) Endocrine and Metabolic
12) Unknown
Developmental And hereditary
1)
2)
3)
4)
5)
6)
Non syndrome hereditary hearing loss
Warrensburg Syn
Alport Syn
Ushler Syn
Inner Ear Anomalies
Large Vestibular Aqueduct Syn
LVA Synd
Infectious disorders
1)
2)
3)
4)
5)
6)
Labyrinthitis
Otitis Media
Viral Infection
Syphilis
Rocky mountain Spotted fever
Lyme Disease
Clinical characteristics of ototoxic deafness
 Bilateral hearing loss
 Hearing loss happens at high frequency
 Reversible or progressive
 With tinitus, vertigo
Pharmacologic Toxicity
1)
Aminoglycosides
15) Dwferoxamine
2)
Ototo[pical preparation
16) Lipid Lowering
3)
Loop Diuretics
4)
Antimalaria
5)
Salicylates
6)
NSAIDs
7)
Analgesic and Anal/Narco
8)
PDEs Inhibitors
9)
Vancomycin
10)
Erythromycin
11)
Cisplatin And Carboplatin
12)
Nitrogen Mustards
13)
Vincristin and Vinblastin
14)
Eflornithine
ANTIBIOTICS WITH GOOD EVIDENCE FOR OTOTOXICITY
Drug
Vestibulotoxicity
Erythromycin
Hearing
Toxicity
Toxic Level
yes
High IV doses only
Usually 2 weeks
Gentamicin
8.6%
minor
Streptomycin
very toxic
minor
dihydrostreptomicin
minor toxic
very toxic
Tobramycin
Yes
minor in 6%
Netilmicin
2.4%
Amikacin
not toxic
13.9%
Neomycin
minor
very toxic
Kanamycin
minor
very toxic
Etiomycin
moderate
Vancomycin
nontoxic
none to
moderate
Metronidizole
toxic (rarely)
unknown
Capreomycin
Less toxic than Gentamicin
In topical ear drops
synergistic with gentamicin
yes
Table from: http://www.tchain.com/otoneurology/disorders/bilat/ototoxins.html See other classes of ototoxic drugs on the same web site.
Ototoxic drug (more than 90)
 Aminoglycoside antibiotics
 Antitumor drug- cisplatin, carboplatin
 Diuretic- furosemide, ethacrynic acid
 Salicylate-aspirin
 antimalarial drug- quinin
Renal disorders
1)
2)
3)
4)
5)
Genetic cause (Alport)
CRF
Hemodialysis
Renal Transplantation
Electrolyte and Metabolic Abn
Trauma
1) Head Injury : Fracture (L&T)
Blunt
2) NIHL
3) Acoustic Trauma
4) Barotraumas: Flying , Diving ,…..
5) Perilymphatic Fistula Congenital : Mondini Synd
Acquired : barotraumas, stapedectomy
Causes of NIHL
Continuous Noise exposure
The extent of hearing loss increases with time of exposure,
and also increases with increasing the intensity of sound
levels to which an employee is exposed
Greatest amount damage occurs in the first 10-15 years
Most scientific evidence suggests that the hearing loss
does not progress once exposure to noise has discontinued
National Occupational Health and Safety Commission
(NOHSC) standard identifies a continuous exposure level of
85dB(A) over 8 hrs and a maximum peak exposure level 140
dB(C)
Effect of NIHL




NIHLs commonly appear as a sloping loss that is most prominent in
the higher frequencies (4k)
Effects speech perception by reducing perception of consonant
sounds (p,b,k,s,z etc) needed for speech clarity.
Vowels usually remain intact as there is often good residual hearing
throughout the lower frequencies.
Result = clients report that they can hear people speaking but not
understand them – the vowels come through clearly but the
important consonants are distorted.
Progression of NIHL ( 0 – 5 years)
Normal Hearing
Mild high frequency loss
= 0%
= 4.6% (40yo), 0% (70yo)
Progression of NIHL (10 – 20 years)
Moderate high
frequency loss
Moderate to severe high
frequency loss
= 16.8% (40yo), 11.9 (70yo)
= 23.8% (40yo), 18.9 (70yo)
Progression of NIHL (25 + years)
Moderate to Profound high
frequency loss
= 67.4% (40yo), 62.5% (70yo)
Ear Anatomy
Clinical characteristics of acoustic neuroma
 Unilateral progressive hearing loss, tinnitus
Acoustic Neuroma
Irradiation
Doses: >45 Gy
Latancy can be 0.5 to 2 year
Radiosurgery
Risk Factor: Aging
preexisting HL
Adjuvant Ototoxic
Neurologic Disorders
1) M.S
2) BIH (Pseudo tumor Cerebri )
Vascular and Hematologic disorders
Migraine
Vertebrobasilar arterial occlusion
Rheological Disorders and blood Dyscrasia
Presbycusis
• Age related H.L
• 30% of >65
• High Freq & Severe in men
• Four Pathologic Types: Sensory Pr
Neural Pr
Strial Pr
Mechanical Pr
Normal Ear
Ear w/ Endolymphatic
Hydrops
Note bulging of membranous labyrinth
(www.tchain.com/otoneurology/disorders/menieres/men_eti.html)
Age and Sex Distribution:
MD is an Equal-Opportunity Disease
Moral: The disease strikes all ages and both
sexes.
Meniere & Endolymphatic Hydrops
• Unpredictability & Variability
• Low Freq
• 30% Bilateral
Delayed E.H Synd
Syphilis
Trauma of Temp Bone
Serous Laby
Stapedectomy
AID
SSNH
•
•
•
•
•
•
•
•
Awaking with it or at over 12hours
5 to 20 per 100000/year
2% to 3% of ENT visits
Peak in Sixth decade
Male=Female
Bilateral is rare
Aural fullness, Tinnitus, Vertigo 40%
Prognosis: 1-Severiy of loss
2-Aduiogram shape
3-Vertigo
4-SDS
5-Age
-Recovery is 30% to 65%
Etiology of SSNHL
• Infectious Dis Viral: mumps,measles,rubella,CMV,HZV,HSV
Meningitis
Syphilis: 2%>
Lyme Dis
Aids
• Neoplasms
• Trauma
Acustic N: 10.2%
Mild & high Freq
All patients should MRI
Head Inj: Hemorrhage, mild loss of H.C
Prilymphatic Fistula: congenital,stapedctomy, barotrauma
Intracochlear M.B
Etiology of SSNHL
• Pharmacologic Toxicity
• Immunologic Dis
• Vascular Dis: PCA occlusion
Migraine
Sickle Dis
Macroglobulinemia
Buerger Dis
Cardiac Surg
Spinal Surg
Treatment of SSNHL
• Apparent Etiology: AB
Withdrawal of drugs
• Idiopathic etiology: Steroids: oral ,Intrathympanic
Improve blood & oxygen
histamine infusion
papaverin, nicotinic acid
carbogen
Dextran, Manitol
pentoxify line
heparin
Iodinated contrast
Treatment of SSNHL
• 10 days couse of prednisolone
• 1mg/kg/day then audiometry
• Valacyclovir 1000mg/TDS/10 days
• Sodium Restriction (2 gr)
• Diuretics
• carbogen