Reference:
- Brunner & Suddarth’s Textbook of Medical-Surgical Nursing, 15th Edition, ISBN 978-197-51-6103-3, by Janice L. Hinkle, Kerry H. Cheever, and Kristen J. Overbaugh (Ch. 59, pp. 1935-1963)
The stapes/stirrup bone accumulates extraneous bone formation (callus) and creates a partial fixation, limiting movement of the stapes and resulting in conductive hearing loss. This may result in complete deafness.
- The cause is unknown. About 50% of patients have a family history. Some studies show measles virus as a factor, and that pregnancy can accelerate formation of bone callus (female sex hormones worsen otosclerosis)
Clinical Manifestations
The primary symptom of otosclerosis is slowly progressing conductive hearing loss beginning anytime between the age of 15 and 45, usually around 20.
- Patients may state that they hear better in noisy surroundings, as the raised frequency and intensity of sound allow the stapes to move properly.
- Constant Tinnitus may be present.
- The tympanic membrane is normal.
- Balance problems: unsteadiness, dizziness, vertigo, other senses of motion.
- Schwartze’s Sign: a pink-blush hue behind the tympanic membrane
- Negative Rinne’s Test
- Lateralized Weber Test
- Bilateral Hearing Loss
Treatment
There is no known cure for otosclerosis.
- Oral fluoride supplementation is a disease-modifying therapy, nearly halting disease progression.
- Dizziness associated with active otosclerosis often respond within two weeks of oral fluoride therapy.
- Stapedectomy: the ear drum is turned forward and the fixed stapes is removed. A stapes prosthesis (teflon or metal) is inserted and attached to the anvil, then the ear canal is filled with ointment. This results in (usually) permanent hearing. Hearing aids should be considered if hearing is still insufficient.
- Stapedotomy: a hole is placed in the oval window and a prosthesis is inserted, but the stapes is not removed.