Otosclerosis

OtosclerosisOtosclerosis
Mr. Ashok bishnoiMr. Ashok bishnoi
Lecturer JINRLecturer JINR

Definition:-Definition:-
 It is metabolic bone disease ofIt is metabolic bone disease of
the ossicles in which normalthe ossicles in which normal
bone is replaced by abnormalbone is replaced by abnormal
“spongy bone” causing fixation“spongy bone” causing fixation
of the stapes bone.of the stapes bone.

Incidence:-Incidence:-
 AgeAge
 The incidence of otosclerosis increases withThe incidence of otosclerosis increases with
age.age.
 The most common age group presenting withThe most common age group presenting with
hearing loss from otosclerosis is 15-45 years,hearing loss from otosclerosis is 15-45 years,

EtiologyEtiology
. Unknown. Unknown
Risk factors-Risk factors-
 Family historyFamily history
 Metabolic, enzyme abnormalatyMetabolic, enzyme abnormalaty
 Infectious, virus was identified in theInfectious, virus was identified in the
lesionlesion
 AutoimmuneAutoimmune,,

PathophysiologyPathophysiology
Due to etiological factorsDue to etiological factors
Distruction of normal bone release enzymesDistruction of normal bone release enzymes
Vestibular & cochlear function impairmentVestibular & cochlear function impairment
CalcificationCalcification(deposition of calcium in the tissue)(deposition of calcium in the tissue)
Fixation of stapes boneFixation of stapes bone
Immobilization of footplate in oval window

Clinical manifestation:-Clinical manifestation:-
 Hearing lossHearing loss
 Schwartz’s signSchwartz’s sign (Normal appearing tympanic membrane(Normal appearing tympanic membrane
(a pink colour is noted through the tympanic membrane)(a pink colour is noted through the tympanic membrane)
 Absent acoustic reflexAbsent acoustic reflex
 TinitusTinitus
 Quiet well modulated voiceQuiet well modulated voice

Diagnostic evaluation:-Diagnostic evaluation:-
 HistoryHistory
 Physical examinationPhysical examination
 Schwartze sign is observed in 10% ofSchwartze sign is observed in 10% of
patients).patients).
 Rinne test: negativeRinne test: negative
 Weber test:Weber test:
AudiometryAudiometry
Otoscopic examinationOtoscopic examination

Image studyImage study
 CT can characterize the extent ofCT can characterize the extent of
the otosclerotic focus at the ovalthe otosclerotic focus at the oval
windowwindow
 CT scan can exclude capsularCT scan can exclude capsular
involvement when patients haveinvolvement when patients have
significant mixed hearing losssignificant mixed hearing loss
 An enlarged cochlear aqueductAn enlarged cochlear aqueduct
may be seen which potentialmay be seen which potential
causes perilymph gusher duringcauses perilymph gusher during
footplate fenestration or removal.footplate fenestration or removal.
 It reveal normal round window andIt reveal normal round window and
normal mastoid pneumatization.normal mastoid pneumatization.

Differential diagnosisDifferential diagnosis
 Ossicular discontinuityOssicular discontinuity
 conductive loss of 60 db usually withoutconductive loss of 60 db usually without
sensorineural componentsensorineural component
 flaccid tympanic membrane on pneumaticflaccid tympanic membrane on pneumatic
otoscopyotoscopy
 type Ad tympanogramtype Ad tympanogram

 Congenital stapes fixationCongenital stapes fixation
 Family history less likely (10%)Family history less likely (10%)
 usually detected in the first decade of lifeusually detected in the first decade of life
 25% incidence of other congenital anomalies25% incidence of other congenital anomalies
(3% for juvenile otosclerosis)(3% for juvenile otosclerosis)
 non-progressive CHLnon-progressive CHL

 Malleus head fixationMalleus head fixation
 when congenital, associated with otherwhen congenital, associated with other
stigmata (aural atresia)stigmata (aural atresia)
 presence of tympanosclerosispresence of tympanosclerosis
 pneumatic otoscopypneumatic otoscopy
 almost always associated with type Asalmost always associated with type As
tympanogram (only in advanced otosclerosis)tympanogram (only in advanced otosclerosis)

 PagetPaget’’s diseases disease
 - diffuse involvement of the bony skeleton- diffuse involvement of the bony skeleton
 - elevated alkaline phosphatase- elevated alkaline phosphatase
 - CT - diffuse, bilateral, petrous bone involvement- CT - diffuse, bilateral, petrous bone involvement
with extensivewith extensive
 -de-mineralization-de-mineralization
 - More commonly crowds the ossicles in the- More commonly crowds the ossicles in the
epitympanum, partially fixingepitympanum, partially fixing
 the ossicular chainthe ossicular chain

 Osteogenesis imperfectaOsteogenesis imperfecta
 presence of blue sclerapresence of blue sclera
 h/o of multiple bone fracturesh/o of multiple bone fractures
 CTCT –– more common involves the otic capsulemore common involves the otic capsule
and to a greater extentand to a greater extent

Surgical interventionsSurgical interventions
 The best surgical candidateThe best surgical candidate
 good health with a socially unacceptablegood health with a socially unacceptable
ABG,ABG,
 a negative Rinne test,a negative Rinne test,
 excellent discrimination,excellent discrimination,
 the desire for surgery after an appropriatethe desire for surgery after an appropriate
period of time for deliberation.period of time for deliberation.
 Younger patients are more likely to developYounger patients are more likely to develop
re-ossification of the stapes footplate overre-ossification of the stapes footplate over
their lifetime.their lifetime.

 Most authors discourage performingMost authors discourage performing
stapes surgery in patients with Meniere'sstapes surgery in patients with Meniere's
disease, especially when it is active.disease, especially when it is active.

 StapedotomyStapedotomy
 Less trauma to the ovalLess trauma to the oval
windowwindow
 Less possibility ofLess possibility of
damaging to the inner eardamaging to the inner ear
 In addition, revisionIn addition, revision
surgery, if required, issurgery, if required, is
easier due to preservedeasier due to preserved
anatomyanatomy
 stapedectomystapedectomy

Non-surgical interventionsNon-surgical interventions
 Amplification:Amplification: hearing aidehearing aide
 Patients who do not want to undergo surgeryPatients who do not want to undergo surgery
for otosclerosisfor otosclerosis
 patients who are not fit for surgery.patients who are not fit for surgery.

 Medical treatment:Medical treatment:
 Usual dose is about 20-120mg of fluoride a dayUsual dose is about 20-120mg of fluoride a day
 Efficacy of the treatment can be evaluated 2 yearsEfficacy of the treatment can be evaluated 2 years
later.later.
 SchwartzeSchwartze’’s sign, and the degree of tinnitus and imbalances sign, and the degree of tinnitus and imbalance
are reassessed, and a CT scan is repeated.are reassessed, and a CT scan is repeated.
 Once the disease was stable, the patient is placed onOnce the disease was stable, the patient is placed on
a life-ling maintenance dose of about 25mg of fluoridea life-ling maintenance dose of about 25mg of fluoride
a day.a day.
 50% of patients have stabilization of their disease,50% of patients have stabilization of their disease,
30% improve, and the rest continue to progress.30% improve, and the rest continue to progress.

 Indications for medical treatmentIndications for medical treatment
 Not surgical candidates,Not surgical candidates,
 Decide against surgery,Decide against surgery,
 Patient with SNHL or vestibular symptomsPatient with SNHL or vestibular symptoms
 positive Schwartzepositive Schwartze’’s sign may be given fluorides sign may be given fluoride
treatments for 6-12 months prior to surgery to inducetreatments for 6-12 months prior to surgery to induce
the focus to mature and potentially prevent thethe focus to mature and potentially prevent the
progression of disease after surgery.progression of disease after surgery.
 determined to be active during surgery, postoperativedetermined to be active during surgery, postoperative
treatment can be initiated.treatment can be initiated.

Otosclerosis

More Related Content

Otosclerosis