OTOSCLEROSIS
 Frequently hereditary autosomal dominant disease
 Most common cause of hearing loss in young adults
 Spongy bone develops from the bony labyrinth, preventing movement of the footplate of the
stapes in the oval window. This reduces the transmission of vibrations to the inner ear fluids and
results in conductive hearing loss.
 The efficient transmission of sound is prevented because the stapes cannot vibrate and carry the
sound as conducted from the malleus and incus to the inner ear.
 Otosclerosis is more common in women; pregnancy may worsen it.
 Although otosclerosis is typically bilateral, one ear may show faster progression of hearing loss.
The patient is often unaware of the problem until the loss becomes so severe that communication
is difficult.
Etiology/Risk Factors:
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Hereditary
Previous measles infection
Possible effect of low fluoride levels
Cytokine imbalance
Bone is a living tissue and contains cells that make, mould and take back up (resorb) bone. Normally bone
is continually being broken down and re-modelled. In otosclerosis, it seems that the re-modelling process
of the stirrup (stapes) - one of the tiny bony ossicles in the middle ear - becomes faulty. New bone is not
made properly and abnormal bone forms. However, the reason why this occurs mainly in the stapes (and
sometimes the cochlea) is not entirely clear.
Pathophysiology
Risk Factors:
Autoimmunity (type II collagen)
Measles virus
Sex hormones (estrogen and progesterone)
Disturbed bone metabolism
Normal bone of the otic capsule is gradually replaced with highly vascular spongy bone  Spongy bone
immobilizes the foot plate of the normally mobile stapes  Conduction of vibrations from the TM to the
cochlea is disrupted and conductive hearing loss results
Clinical manifestations:
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Low volume speech – due to the conductive nature of hearing loss, patients perceive their voice
as louder than it actually is
unable to hear low-pitched or low-frequency sounds such as a whisper
Paracusis Willisii – a patient hears better when there is a lot of background noise
Dizziness and balance problems
Tinnitus
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slowly progressive, conductive or mixed hearing loss
Diagnostic and examination:
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History and physical examination
Otoscopic examination - reveals a reddish blush of the tympanum (Schwartz’s sign) caused by the
vascular and bony changes within the middle ear.
Rinne test - Bone conduction is better than air conduction
Weber test
Tuning fork tests and an audiogram demonstrate good hearing by bone conduction but poor
hearing by air conduction (air-bone gap).
*an air-bone gap indicates a problem in the outer or middle ear
A difference of at least 20 to 25 dB between air and bone conduction levels of hearing is seen in
otosclerosis.
Audiometry - audiogram confrms conductive hearing loss or mixed loss, especially in the low
frequencies.
Tympanometry – shows very little movement of the eardrum; this signifies that the ossicles or
middle ear bones have stiffened up
Collaborative Therapy
• Hearing aid - Amplification of sound by a hearing aid can be effective because the inner ear function is
normal.
• Oral administration of sodium fluoride with vitamin D and calcium carbonate
- matures the abnormal spongy bone growth and prevent the breakdown of the bone tissue
- stabilizes the hearing loss associated with otosclerosis by retarding bone resorption and
encourage the calcification of bony lesions.
Surgical Management
Stapedectomy - involves removing the stapes superstructure and part of the footplate and inserting a
tissue graft and a suitable prosthesis
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Surgeon drills a small hole into the footplate to hold a prosthesis which bridges the gap between
the incus and the inner ear, providing better sound conduction.
The majority of patients experience resolution of conductive hearing loss following stapes
surgery. Balance disturbance or true vertigo may occur during the postoperative period for
several days.
Long-term balance disorders are rare.
Stapedotomy:
 Microdrill or laser surgical treatment involves opening the footplate (stapedotomy) or replacing
the stapes with a metal or Teflon substitute (prosthesis).
 Performed with the patient under conscious sedation.
 The ear with poorer hearing is repaired first, and the other ear may be operated on within a year.
 Immediately after surgery the patient often reports a significant improvement in hearing in the
operative ear.
 Because of the accumulation of blood and fluid in the middle ear during the postoperative period,
the hearing level decreases initially, but it improves gradually with healing.
Nursing Management:
Nursing management of the patient undergoing surgery to correct otosclerosis is similar to that for the
patient having a tympanoplasty.
 Use Gelfoam on the incision flap to limit bleeding.
 Place a cotton ball in the ear canal, and cover the ear with a small dressing. The patient may
experience dizziness, nausea, and vomiting as a result of stimulation of the labyrinth during
surgery.
 Some patients demonstrate nystagmus because of disturbance of the perilymph fluid – the
patient should take care to avoid sudden movements that may bring on or exacerbate vertigo.
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Actions that increase inner ear pressure, such as coughing, sneezing, lifting, bending, and straining
during bowel movements, should be avoided.
https://www.nidcd.nih.gov/health/otosclerosis#:~:text=of%20the%20ear,What%20causes%20otosclerosis%3F,becomes%20impaired%20(see%20illustration).
https://patient.info/ears-nose-throat-mouth/hearing-problems/otosclerosis
Hinkle, J. & Cheever, K. (2014). Brunner & Suddarth’s Textbook of Medical-Surgical Nursing (13th ed.).
Lippincott Williams & Wilkins
Lewis, S., Dirksen, S., Heitkemper, M., & Bucher. L. (2014). Medical-Surgical Nursing: Assessment and
Management of Clinical Problems (9th ed.). Elsevier