Sudden and Fluctuant Sensorineural Hearing Loss

Prakash Adhikari 2nd Year M.S.Resident (ENT-HNS) Ganesh Man Singh Memorial Academy of ENT and Head and Neck Studies, TU Teaching Hospital, IOM,Kathmandu,Nepal

ROADMAP

Introduction Definition Causes ISSNHL Investigations Prognostic factors Treatment modalities Conclusion Take home message

Introduction-SSNHL

Devastating to patients Frustrating for physicians Definitive diagnosis and treatment still unknown First described by De Klevn in 1944

Statistics

15,000 reported cases per year worldwide 4,000 cases per year in the U.S. Nepal et al study in TUTH-46 cases in between 2002-2005 Highest:: 50-60 years Lowest:: 20-30 years M=F 2% bilateral 90% of cases are idiopathic

Definition

Several Most accepted: 30dB SNHL More or equal to 3 contiguous frequencies Less than 3 days (Wilson et al) More or equal to 20dB (Haberkamp and Tanyeri) More or equal to 20dB in no more than 1 week (Kronenberg et al)

Causes of sudden or fluctuating SNHLCOCHLEAR

Traumatic Inflammatory Vascular Haematological conditions Autoimmune disease Endolymphatic hydrops Metabolic disorders Skeletal system Ototoxicity Miscellaneous

Retrocochlear and central nervous system

Meningitis Multiple sclerosis Friedrichs ataxia Amyotrophic lateral sclerosis Xeroderma pigmentosum Tumors Central deafness

Idiopathic

Cochlear causes- Traumatic

Electricity Rupture of tympanic membrane From telephone during thunderstorm Cordless-complex signal 3 cases reported-HL-during use of cordless during lightening (Singleton et al 1984)

Traumatic HL

Breaks in the membranous labyrinth Intracochlear Menieres Oval and/or round window perilymph fistula History inciting event Blow to the head Lifting a heavy object Exposure to sudden changes in barometric pressure High risk population Post stapedectomy Inner ear anomalies

Traumatic SHL

Treatment

Avoid lifting > 10 lbs. Avoid straining If improvement 6 weeks of light activity If no improvement surgery

After 5 days

Middle ear exploration Patching of perilymph fistula

Inflammatory-BacterialAcute otitis media Very few cases are reported Typhoid fever 2nd to 3rd weeks Usually unilateral Female preponderance Reversible in few cases

Spirochates- syphilis

Congenital B/L profound HL-fluctuation Involve low and high frequencies\poor speech discrimination Late syphilis 5%present with SSNHL Sudden detoriation in 15%

Mycoplasmas

Case reported-1984 by Nishioka et al. B/L involvement Treated with minocycline n steroids No improvement Bullous myringitis Rare association Untreated casesimprovement in few M. pneumonia also isolated

Chlamydia

C. trachomatis and C. psittaci Darouger et al, 1978, reported B/L involvement No improvement with steroids

Brucellosis

B. melitensis. B.abortus, B. suis Vestibulocochlear nerve commonly affected Serological tests Tetracycline and rifampicin Failed to reverse hearing loss

Lyme disease- B.burgdorferi

Transmitted by tick Facial palsy commonly associated Ix- IFA.ELISA,IMMUNOBLOTTINGS Treated with Benzyl penicillin No satisfactory results

Rickettsiae-typhus

R. prowazekii Hearing loss-early and serious

two cases. (Tsiachris D et al.2008). resolved automatically without administration of specific treatment.

ViralMumps

Incidence-0.1%,80% unilateral Three common presentation Insidious unilateral complete Unilateral partial Bilateral completeMurakami and Muzushima,1985,n=53

HL- unilateral, profound and permanent Haematogenous infection theory Inflammatory change

Measles

5-10% Measles rash Assymetric permanent B/L HL affecting higher frequencies Suzuki et al-mumps deafness in one ear and rubella infection following HL in opposite ear Improved with betamethasone

Chickenpox

Reported in a 14 month old infant1983 B/L sudden HL No improvement

Varicella zoster virus

Sudden deafness with facial palsy Oral acyclovir Watch for RFT 70% had herpetic infections (Wilson-1986,n-60) MRI- enhancement in facial and cochleovestibular nerves concluded relation of herpes simplex virus and sudden deafness reactivation of a latent infection - role in the aetiologyKoide et al-1988,n-60 -

Human spumaretrovirus-HSRV

Few cases were reported in 90s, isolated from patients neoplastic and degenerative diseases Bilateral HL Infectious mononucleosis 1% nervous system involvement Temporary bilateral HL

Lassa fever

Arenavirus infectionCummins et al-1990,n- 69

29% incidence HL

Liao et al study 1992,n-12

88% bilateral Ribaviarin started Improvement in 8 cases

HIV AND AIDS

one third had abnormal PTAand Wash, 1989)

(Brichall et al,1992,n-18)

Reported as a presenting symptom

(Timon

Bilateral HL Neurotropic and lymphotrophic virus-never been cultured from 7th cranial nerve or spiral ganglion cells. (Morris and prasad,1990) Temporal bone reports by AIDS. (Michaels et al1994)

Protozoa

Toxoplasmosis Lymphadenopathy-commonest Hearing rarely affectedKatholm et al,1991

SSNHL-Both ear. Improved hearing with sulphadiazine and pyrimethamine Buergers disease

Iatrogenic

Radiotherapy Significant correlation between total radiation dose to inner ear and observed hearing impairment. (Garu et al,1991,n-22)

Higher frequencies involved

Postoperative

Microembolism involving cochlear division of the IAC. Pump filters may prevent microemboli Hypothermia produces latencies increased of wave I-IV. (Ness et al 1993) Almost always unilateral adrenalectomy (Journeaux et al 1990) Hochermann and Reimer 1987 - bilateral HL

Spinal anaesthesia

Transient hearing loss reported Panning etal 1983,n-100::: in urological patients found 8 cases. Audiogram done in 3 cases Low frequency involvement Improved with no therapy

WANG 1987.Fog et al 1990 and Sundberg et al 1992

Shape & position- tip of the needle 26 was to preferred than 22GLee and Peachman,1986 reported

SSNHL following C/S, Blood patch with 10ml Hearing improved. Hardt,1998 reported similar result occurs in wholly or partially patent cochlear aqueduct and occurs via the release of perilymph into the CSF.

Vascular cause

HYPERTENSION Dobozi nad Greig (1972)- no evidence of atherosclerosis Drettner et al (1975)- low frequency hearing was related to cardiovascular disease events Kikuchi et al (1993),n=102 MRI - slow blood flow in the vertebrobasilar system Mark et al (1992)- MRI with Gad scan showed cochlear enhancement on the side of HL.

Hypercoagulation

Recurrent episodes of thrombosis Stria vascularis has a slow blood flow in those with a high haematocrit value no difference with coagulation test. (Lalanne et al 1992 n=79)

Viscosity

strong correlation between whole blood viscosity and hearing impairment at all frequencies. Gatehouse et al (1989) hydroxyethyl starch pentoxifylline infusions-superior results. (Desloovere et al 1991)

Haematological

Anaemia- rarely associated Case reports on iron def, megaloblastic and aplastic anaemia Prognosis poor Polycythaemia vera

Cerebral blood flow significantly reduced B/L SSNHL reported Improved after phlebotomy( Davis and Nilo 1995).

Sickle cell disease

Gradual onset/ fluctuant or SSNHL Sickling and impaired blood flow in the cochlear venous system with secondary anoxia of the hair cells and stria vacularis. Bilateral SSNHL Mace AD et al J Laryngol Otol. 2008

Thalassaemia

B/L high freq SNHL in a patient on desferrioxamine (Back,1980, n=52) (Oliveri et al, 1986,n=89)-22::: abnormal Hearing Low serum Ferritin was also a risk factor

Waldenstroms macroglobulinaemia

Characterized by retinal changes, abnormal bleeding tendencies, generalized weakness and dyspnoea Leukaemia Common in ALL CLL- few reported Treatment with cyclophosphamide and prednisolone improved hearing

Cryglobulinaemia

SLE, multiple myeloma or macroglobulinaemia Autoimmune disease

Closely related- 30% associated with SSNHL ANA,ATA +ve CD3+,CD4+ peripheral lymphocytes and marked decrease of CD8+.

Non-organ specific autoimmune disease

SLE Cyclophosphamide and steroids fail to improve hearing ANF, Ds DNA ACLA Systemic vasculitis ANCA, proteinase 3 and myeloperosidase PAN b/L deafness, treated with prednisolone improved Obliterative vasculitis of the labyrinthine artery or its branches resulting in diffuse or focal areas of ischaemic necrosis

Cogans syndrome

4% deafness in syphilitic keratitis (Cogan 1945) Non syphilitic keartitis- progressive HL

Aortitis 10%

Hearing fluctuates with disease exacerbations and remissions Majority develop bilateral deafness (67%) MRI shows narrowing or obliteration of parts of the vestibular labyrinthSTEROIDS/ COCHLEAR IMPLANTATION

Relapsing polychondritis

Ocular lesions, HL and dizziness U/L or B/L Usually accompanied by abrupt cessation of steroids and reduction of medicines Six diagnostic criteria

Wegeners granulomatosis

Three principal components NGL in upper or lower respiratory tract Generalized focal necrotizing vasculitis of arteries and veins GN Occ. reversible Treated with cyclophosphamides and steroids Giant cell arteritis B/L, sudden Biopsy Protein electrophoresis Prednisolone

Kawasaki disease

Self limited acute vasculitis 7th cranial nerve palsy Diagnostic criteria Mechanism of SSNHL not known Usually B/L. CHL may be present

Takayasus disease

Absence of pulse in upper extremities due to the obstruction of the aortic arch branches HPE- no vasculitis Kanzaki et al 1993,n-17- 7 had SSNHL No improvement of steroids Behcets diseaseBrama and Fainaru,1980,n-16-

10 had SSNHL.

Endolymphatic hydrops

5% develop SSNHL Hallberg 1956- 57/1270.Takahara et al, 1974,Sando et al-1977:

cases at autopsy Fluctuant HL Classic symptoms- endolymphatic hydrops GTT/PTA

found two

Metabolic disorders

Renal failure 80% of case with ARF and 52.4% with CRF improved with treatment. B/L symmetrical

Alports syndrome

Slowly progressive and high freq involved C/F: HTN, proteinuria and haematuria Gubler et al 1981,n-58, one present as deafness, 37 showed HL Always bilateral PTA- trough shaped, sloping and flat ( Pintelman,1976)

Temporal bone studies- degeneration of stria vascularis, loss of cochlear neurons, atrophy of spiral ligaments or loss of hair cells

Renal transplantation

Improve hearing after transplant Mc Donald et al 1978 - HL following transplant,n-4. Neomycin/ cyclosporin Renal tubular acidosis IgA nephropathy

Diabetes Mellitus

Diabetics- deafer in lower freq than control Wilson et al 1982- diabetics fail to recover as well in higher frequencies Nottingham 1981- did not find any difference between two groups on PTA. Central disturbance of auditory pathway and microvascular complication

Wackym and Linthicum 1986

Microangiopathic involvement of endolymphatic sac had significant greater HL. Diet- severe HL,hypoglycemia oral, insulinless loss Refsums disease AR Retinitis pigmentosa, chronic polyneuropathy, ataxia Anosmia, HL (cochlear), cardiopathy

Hyperlipidaemia

Not signficant correlation. Hypothyroidism Symmetrical B/L HL ? Association

Drettner et al 1975, n -1000.

-13% improved hearing when they became euthyroid No improvement- Parving et al 1983,n-15Vant Hoff and Stuart 1979.n-48

TUTH STUDY

45.7% HAD SYSTEMIC DISEASE DM alone-7 HTN alone-3 Hyperlipidemia alone-2 DM+HTN-6 DM+Hyperlidemia-2 DM+HTN+Hyperlipidemia-1

Ototoxicity

Interferon Contraceptive pills Dantrolene/Mianserin- sudden B/L HL- no imrovement Sudden sensorineural hearing loss after heroin injection. Schrock A, Eur Arch Otorhinolaryngol. 2008May;265(5):603-6.

Iloprost-induced sudden hearing loss. Dursun E, J Laryngol Otol. 2007 Jun;121(6):609-10.

Iloprost may be a potentially ototoxic drug, causing sudden hearing loss. completely reversed in eight days with conservative therapy.

Vaccination

Tetanus antitoxin. n-1, in tetanus toxoid. (Mair and Elverland,1977,n-8) Whoopong cough, rabies, small pox. But not on diptheria or oral polio Cause- local hypersensitivity or AgAb rxn

CO Intoxication

CarboxyHb- deprive vital organs of O2 Chronic- permanent symmetrical high freq loss Acute- B/L asymmetric.improved in 4 weeks. May be fluctuant U shaped audiogram

MiscellaneousUlcerative colitis

B/L HL Steroids + immunosuppresives responded. Jacob et al1990

Scleroderma Cyclophosphamide- B/L mixed HL- improved Sarcoidosis SSNHL may be only complaint Fluctuant B/L Increase calcium, ESR and ACE,CXR- hilar adenopathy Biopsy- non caesating granuloma Prednisolone- improve hearing

Retrocochlear and CNS

Meningitis- B/L Cryptococcal meningitis and sudden deafness (Maslan et al 1985) Viral and TB can also cause

Multiple sclerosis

3% have hearing problem 25% vertigo Multiple areas of demyelination of CNS U/L Absence of wave II to IV Friedrich ataxia No obvious cause Amyotrophic lateral sclerosis (Van Laeres deiseae) Hearing loss first manifestation

VKH syndrome

B/L HL Returned to normal Xeroderma pigmentosa B/L HL absence of tone decay, absent stapedial reflexes

Tumors

Vestibular schwannoma 10% sudden (Higgs 1973,n-44) In between 10-15% MRI with Gadolinium- compression of vasculature within the bony IAM Metastasis in CP angle: from breast, bronchus, prostate.

Central deafness

U/L or B/L Earnest 1977, B/L cerebral infarcts B/L cerebral lesions- Tanka et al,1991. Creutzfeldt-Jakob disease (Tobias et al,1994) report a case with cortical deafness

Lacunar syndromes

Cortical encephalitis No improvement no worsening HL- first symptom B/L assymetric HL Speech discrimination-poor Prednisolone + cyclophosphamide Alzheimers disease Loss of dendritic spines and axionic collaterals

Noise

SSNHL- following concerts Acute acoustic traumaEmmett, 1994:

Idiopathic SSNHL

Definitions Several Most accepted: 30dB SNHL More or equal to 3 contiguous frequencies Less than 3 days (Wison et al) More or equal to 20dB (Haberkamp and Tanyeri) Moe or equal to 20dB in no more than 1 week (Kronenberg et al)

Proper history Noise trauma, barotrauma, direct temporal bone trauma, medication

History

Time course Associated symptoms

Vertigo/dizziness Aural fullness Tinnitus

Ototoxic drug use Symptoms of URTIs H/O head trauma, straining, sneezing, nose blowing, intense noise exposure H/O flying or SCUBA diving

History

PMH:

Autoimmune disorders Vascular disease Malignancies Neurologic conditions Hypercoagulable states Sickle cell disease (African Americans)

PSH: stapedectomy or other otologic surgeries

Physical Exam

Complete H&N exam in everyone

Ears: r/o effusions, cholesteatoma, cerumen impaction Weber/Rinne Neurologic exam cerebellar findings

Tandem gait Romberg Nose to finger, heal to shin

Vestibular Dix-Hallpike test

Suggested categorization of SSNHL

SSNHL of specific cause Possible idiopathic SSNHL or probable idiopathic SSNHL Definite idiopathic SSNHL

Epidemiology

Incidence: Vary according to age and possibly sex 8 per 100,000 per year (Wu et al,2006). Specific cause found in less than 5% Equal in both gender Bilateral less than 1%

Age distribution

Shai and Sheehy (1976)

Three fourth are more than 40 years 4% B/L Adult B/L-possibility of HIV

Etiopathogenesis

Postulated causes Viral infection Vascular occlusion Membrane breaks Immunological Activation of cochlear nuclear factor kappa B.

Schuknecht- vascular lesons, membrane breaks and viral cochleitis (Temporal bone studies) Hypothesis-activation of cochlear NFkB by endogenous and exogenous stimuli.- no direct proof. Immunologic phenomena- Vasama and

Linthicum.2000,n-12. Vascular aetiology (Merchant et al) extensive cochlear

fibrosis and inner ear ossifications-not convincing. Other studies-disturbance of microciculation of the cochlea produce cochlear damage and hyperviscosity with sludging of red cells and consequent hypoxia.

Temporal bone studies

Shows viral cochleitisDenovan,1986,n-12). Kheterpal,1990.n-12:

(schunknecht and

ISSNHL due to neurotrophic viruses

Precipitating Factors

Preceding viral infection:30-40% 3 group of viruses 1. virus causing ARD- Influenza,parainfluenza, rhinoviruses

No confirmed seasonal viruses 2.Poliovirus,coxsackie,rubella,EBV,adenovirus type 3 & HSV

3. Mumps, measles and varicella zoster

Prognosis

47%-63% spontaneously resolve Four prognostic variables

Time since onset age Tinnitus / Vertigo Audiogram type

Prognosis

Prognosis

Age

Tinnitus:

80% alarming, 25% preceeding Dose not affect the outcome In Danino et al, 1984- favorable prognostic sign Tinnitus present in 71% who recovered compared with 39% who did not

Prognosis

Vertigo 29% affected vs. 55% not affected

Audiogram type

Prognosis

8KHz

Wilson (1980)

Prognostic factors

Vertigo not statistically significant Age less than 40 years favorable for recovery Type of audiogram Midfrequency loss with best recovery Profound loss less likely to have recovery Loss between 40 dB 85 dB more likely to respond to steroid therapy

Investigations

Battery of tests CBC RFT, Electrolytes Glucose Lipid profile Serology Autoantibodies TFT MRI

+/- Auditory brainstem response (ABR) and otoacoustic emission (OAE) ENG if vestibular symptoms and/or signs are present

Audiogram

Pure tone Speech discrimination Tympanometry Stapedial reflex

Our protocol

Hb,TC,DC,ESR Bl.Glucose F/PP LFT Coagulation profile TFT Lipid profile RFT ANA Serlogy Urine RME CXR MRI in selected cases PTA- EVERY 3RD DAY

AIED

Diagnosis

Based on Hearing loss and response to treatment Hughes

Lymphocyte transformation test

Sensitivity 50-80% Specificity 93% Positive predictive value 56-73% Sensitivity 88% Specificity 80% Positive predictive value 92%

Western blot

Diagnostic Testing

MRI:

Rule out cerebellopontine angle tumors Multiple sclerosis ischemic changes

13% of patients with acoustic tumors present with SHL 23% may recover hearing

2000 survey of 100 ENTs (43% otologists) in the United Kingdom

78% - CBC, ESR, Syphilis serology 38% - MRI on initial visit 98.5% - steroids 41% - Carbogen 31% - acyclovir

Outcomes

Complete spontaneous recovery seen in 5075% Wilson defined recovery into three cateories Complete-within 10dB Partial recovery-within 50% No recovery-less than 50%

Cinamon et al- 75% spontaneous recovery, Wilson et al 47% spontaneous recovery

Treatment

Treatment

Therapy for ISSNHL is controversial Difficult to study

High spontaneous recovery rate Low incidence Makes validation of empiric treatment modalities difficult

TREATMENT

Increasing cochlear blood flow No proven value Betahistine-histamine like effect on H1 receptors in the cochlea vasculature leading to increase in cochlear blood flow Glycerol-iv in rabbit

Pentoxiflline / oxpentyfylline

Phosphodiesterase inhibitor and haemorheological agent Increase oxygen delivery to tissues Iv given in SSNHL of vascular origin Probst et al,1992: no significant diffeence.

Calcium antagonists

Increase cerebral blood flow Nifedipine, nimodipine No significant difference with other drugs (eg:nimodipine Vs naftidrduryl) Further trials needed

Diatizone meglumine (Hypaque)

1 ml of iv hypaque prior to vetebral angiographysignificant hearing improvement Huang et al 1989-not better than spontaneous recovery-65%.

Low molecular weight Dextran (Rheomacrodex) 10%solution either in 5% dextrose or in normal saline no significant benefit Allergic rxnHydroxyethyl starch/Hetastarch-Hespan

Artificial colloid derived from waxy starchmyelopectin 6% colloidal solution in 0.9% sodium chloride No difference in hearing Pruritis

5% carbon dioxide. 95% oxygen (carbogen)

Cerebral vasodilator 10% co2 dangerous After carbogen inhalation- perilymphatic oxygenation of 8.6mmHg rose to 14.8mmHg 95% o2 and 5% Co2 for 30 mins 8 times per day at intervals of one hour. (Fisch et al 1984) 3/4th pts improved Giger 1979,n-55: Carbogen or iv infusion with papaverine and Dextran No difference on 5th day but better result at 1 year It mat improve spontaneous rate recovery in sudden deafness Grandis et al study.1993- same as spontaneous recovery (65%)

Hyperbaric oxygen

No proper trials Can be considered Anticoagulants Heparin-chosen in initial stages Reduce serum lipid level Also binds with histamine Donaldson 1979.n-23: iv heparin sodiumrecovery (70%) same as spontaneous (66%)

Defibrinogenation therapy

Batroxobin Reduction in serum fibrinogen Thrombin like enzyme-Gicopetide Prostaglandins Synthesized by vascular structures of the lateral wall of the inner ear (stria vascularis and spiral ligament) PGI2 and PGF2alpha found in perilymph Inj Aspirin intraperitoneally-decrease in perilymph Olszewski et al 1985-n-22, prostacyclin:55%recovery,9 partial recovery Olszewski et al 1990: 87% complete recovery

Other therapies

Vitamins- B1,B12,B6,C,A,E INTERFERON Iron therapy Zinc Ginko extract diazepam

Treatment

1987 Wilkins and associates

shotgun regimen dextran, histamine, Hypaque, diuretics, steroids, vasodilators, carbogen No difference between treated and nontreated patients No control group Treatment for only three days

Steroid therapy

Treatment of choice when loss is retrocohclear Wilson et al,1980: double blinded clinical trial-stastically significant effect on hearing recovery in patients with moderate HL

Dose of oral steroids:

RCTs

acyclovir+ prednisolone Vs Prednisolone: no difference (Stokroos 1998), (Uri 2003) prednisolone / placebo / carbogen: no difference (Cinamon 2001) carbogen Vs carbogen+iv Mgso4: later is better (Gordin 2002) prednisolone +acyclovir Vs prednisolone+ acyclovir+intratympanic methylprednisolone: methylprednisolone better (Xenellis 2006)

Cinamon (2001)

Results

Overall improvement in PTA at follow-up (73%) Steroid 80% Placebo 81% Carbogen 55% Placebo inhalation 77% Not statistically significant Low frequency loss improved more High frequency loss improved less Patients without vertigo have better outcome

Trends:

The Newest Treatment: Intra-Tympanic Dexamethasone

IT dexamethasone, methylprednisolone & hydrocortisone all results in higher perilymph concentration of steroid than systemic delivery of steroids

Parnes (1999)

Potency corrected levels in perilymph after IT administration

Parnes (1999)

Potency corrected levels in endolymph after IT administration

OtolaryngologyHead and Neck Surgery (2007) 137, 74-78

Intratympanic steroid treatment improved hearing loss in (55%).

Kopke (2001)

IT Delivery via Microcatheter

Methylprednisolone (62.5 mg/mL) delivered continuously for 14 days at rate of 10 L/hour using pumpSilverstein (2002)

N-48, refractory hearing loss after systemic steroids Dexamethasone 4-24 mg/mL with MicroWick 23% had improvement of PTA of at least 10 dB

Silverstein (2002)

GroupXenelis (2006) Batista (2005) Slattery (2005) Banerjee (2005) Herr (2005) Guan-Min (2004)

StudyProspective, controlled Prospective, PSSNHL Prospective Retrospective review Retrospective review Prospective, randomized, contolled Academy Presentation Prospective

SteroidMethylprednisolone Dexamethasone Methylprednisolone Methylprednisolone Dexamethasone Dexamethasone

DeliveryInjection Injection Injection Via PET

Improvement47% (PTA) 20% (PTA) 55% (PTA/SDS) 69%, 10 days (PTA) 31%, >10 days 53% (PTA/SDS)

MicroWick Microcatheter Injection

Dexamethasone

53% Treatment (PTA) 7% Control

Silverstein (2002) Gianoli (2001)

Dexamethasone

MicroWick

23% (PTA) 35% (SDS) 44% (PTA) 100%,6wk(PTA/SDS) 0% >6wk

Dexamethasone Methylprednisone

Via PET Microcatheter

Kopke (2001) Prospective

Sudden Sensorineural Hearing Loss

Advantages to IT steroids

May be used when systemic steroids are contraindicated or refused Greater concentration achieved at target end organ May be performed in outpatient setting Possible use for salvage of hearing Relatively low complication rate

Sudden Sensorineural Hearing Loss

Challenges for IT steroids

Not well established as primary treatment strategy Dosing? Best delivery technique? Long term effects? Why does it work? .... Sometimes

No high quality evidence to support the contention that any particular treatment in ISSNHL is more effective than placebo ? Risk of short course of oral steroids

Ongoing Study

National Institutes for Health (NIH) study

Multi-centre RCT Oral steroids vs. intra-tympanic steroids

Conclusion

No statistically significant benefit of:

Steroids over placebo Anti-virals plus steroids over steroids alone Steroids over other active treatment

Wilsons often-misquoted study was not a randomized controlled trial

Conclusion

Questionable internal & external validity but positive results favouring:

Batroxobin Magnesium Vitamin E Hyperbaric oxygen Intra-tympanic dexamethasone

Conclusion

SHL is devastating to patients Frustrating for physicians to dx and tx Thorough H&P Rule out treatable cause Directed labs, Audiogram, MRI Discuss risks, benefits, and alternatives of treatment with the patient Treat the disorder aggressively Rehabilitate those whose hearing does not improve Follow patients for development of associated diseases and for contralateral ear disease

Sudden Sensorineural Hearing Loss

Challenges

True incidence is not known

Patients with spontaneous recovery usually do not present to an otolaryngologist

Patients may present beyond what is considered to be therapeutic window Etiology still unclear Relative paucity of studies examining treatments based on prospective, double-blind, randomized, controlled trials

Sudden Sensorineural Hearing LossTake Home Messages:

SSNHL is an otologic emergency Systemic steroids are mainstay of therapy

Prednisone 60 mg/day for 3-5 days, tapered 5-7 days Better prognosis if treatment started early (within 4 weeks of onset) IT steroids may be an alternative when systemic steroids are contraindicated IT steroids is another option when oral steroids fail to restore hearing