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OTOSCLEROSIS DR.P.KARTHIKEYA
NPROF&HOD
DEPT.OF ENT07.03.2016
OBJECTIVESDefinition of otosclerosisEtiology of otosclerosisTypes of otosclerosisClinical features of otosclerosisDiagnosis of otosclerosisMedical management of
otosclerosisSurgical management of
otosclerosis
A primary disease of otic capsule in which irregular spongy bone replaces the dense endochondral layer of bony otic capsule, thereby fixing the footplate of the stapes and causing conductive hearing loss.
OTOSCLEROSIS
HISTORY OF OTOSCLEROSIS1704 – Valsalva first described stapes
fixation1857 – Toynbee linked stapes fixation
to hearing loss1890 – Katz was first to find
microscopic evidence of otosclerosis1893 – Politzer described the clinical
entity of “otosclerosis”
ETIOLOGYExact etiology – not known1) Idiopathic – Remnants of
embryonic cartilage resting in the otic capsule may be the etiological factor.
2) Heredity3) Hormonal – Symptoms
increase during pregnancy and menopause.
4) Van der Hoeve syndrome – Osteogenesis imperfecta,
otosclerosis, Blue sclera
5) Associated with Paget’s disease.6) Enzymatic theory – (Latest)
Imbalance in trypsin / antitrypsin in the inner ear fluid initiates otosclerosis.
7) Metabolic and immune disorders.8) Anatomical and Histological
anomalies of temporal bone.9) Recent – Relationship between prior
infection with measles virus and later development of otosclerosis.
INCIDENCE0.5-1% of total population Female: Male (2:1) 20 – 30 years of age Common in white races, but
common in Indians and low in chinese and Japanese.
Usually bilateral (85%)
TYPES1) Stapedial otosclerosis : (common)
Sites – 1) Fissula ante fenestrum
2) Fissula post fenestrum
3) Circumferential 4) Biscuit type or rice
grain type with delineated margins
5) Obliterative type
2) Cochlear otosclerosis:
Involves the region of round window and labyrinth in the absence of stapes
fixation
Sensorineural hearing loss due to liberation of toxic materials from abnormal bone into inner ear.
3) Malignant otosclerosis Severe type of cochlear
otosclerosis Starts early in life and
progresses rapidly.4) Combined otosclerosis –
mixed hearing loss.5) Histological otosclerosis:
9 – 12% cases, No clinical features but
histologically the focus is present.
PATHOLOGYGrossly – appears as chalky white or
yellow focus (inactive) or red in colour due to increased vascularity (active)
Microscopically – 1) In immature (active) foci, there are
numerous marrow and vascular spaces with plenty of osteoblasts and osteoclasts which stains blue on H&E stain. (Blue mantle)
2) In mature (inactive) foci, there is less vascular spaces with lot of fibrous tissue which stains red on H&E stain
CLINICAL FEATURESSymptoms
1) Hearing loss – conductive
2) Tinnitus
3) Paracusis willisi
4) Monotonous, well modulated soft speech.
5) Vertigo
SIGNS1) TM : normal and mobile
2) Schwartze sign or Flamingo pink appearance
3) TFT : Conductive hearing loss
4) PTA : Carhart’s notch
5) Impedance Audiometry – Type As curve
TYMPANOMETRY
DIFFERENTIAL DIAGNOSISOssicular discontinuityCongenital stapes fixationMalleus head fixationPaget’s diseaseOsteogenesis imperfecta
Natural History of Otosclerosis90% of all cases are never clinically
apparentFoci begins in childhood
Most commonly becomes symptomatic in the 3rd and 4th decades
After clinical presentation◦ Conductive hearing loss progressive◦ Periods of quiescence and deterioration◦ Worsening tinnitus◦ Associated SNHL (rarely purely SN)
Tab. Sodium fluoride Dose : 50 – 75 mg/day, Duration : 3 months – 2 years
Function 1) helps to hasten the maturity of active
focus and arrest further progression of cochlear loss
2) It has antienzymatic action on proteolytic enzymes which are cytotoxic to cochlea.
MEDICAL TREATMENT
Indications: Cochlear otosclerosis Active stapedial otosclerosis
Side effects : Fracture of long bones and spine due to
fluorosis.Nephritis. Gastritis
Contraindications: Pregnancy & lactation Patient with kidney stones / nephritis Patient with RA
History of Stapes SurgerySamuel Rosen
◦1953 – first suggested mobilization of the stapes Immediate
improved hearing
Re-fixation
History of Stapes SurgeryJulius Lempert
◦ Popularized the single staged fenestration
in the horizontal canal with a tissue graft covering
◦ >2% profound SNHL◦ Rarely complete closure of
the ABGJohn House
◦ Further refined the procedure Popularized blue lining the
horizontal canal
History of Stapes SurgeryJohn Shea
◦1956 – first to perform stapedectomy Oval window
vein graft Nylon prosthesis
from incus to oval window
SURGICAL TREATMENT1) Lempert’s fenestration operation
(1938)2) Rosen’s stapes mobilisation
(1953)3) Shea’s stapedectomy (1958)4) Stapedotomy – small fenestra
stapedectomy. (Laser can be used)
Hearing Aids
STAPEDECTOMY
Indication: Stapedial otosclerosis (inactive)
Selection of patient: Rinne negative Audiogram : AB gap at least 20dB Should have good speech
discrimination
Contraindications:1. Only hearing ear2. Otitis externa, CSOM3. Cochlear otosclerosis4. Young children / old age5. Athletes, drivers, frequent
air travelers, those who works in noisy environment.
6. General medical illness7. Pregnancy.
Complications
1. Perforation of ear drum2. Total SN loss3. Chronic vertigo4. Facial nerve paralysis5. Perilymph fistula6. Granuloma.
THANK YOU