Pediatric Otosclerosis

Updated: Dec 01, 2023
  • Author: Joe Walter Kutz, Jr, MD, FACS; Chief Editor: Ravindhra G Elluru, MD, PhD  more...
  • Print
Overview

Practice Essentials

Otosclerosis is a genetically mediated metabolic bone disease that affects only the human otic capsule and ossicles. [1, 2] Its mode of inheritance is autosomal dominant, but penetrance and expressivity both vary.

Usually, symptomatic hearing loss from otosclerosis first develops early in the third decade of life, though onset can occur during childhood. Otosclerosis is well recognized as a cause of conductive hearing loss from fixation of the stapedial footplate in the oval window niche. [3] Less well recognized is that otosclerosis can involve other portions of the cochlea and produce sensorineural hearing loss (SNHL).

The incidence of cochlear otosclerosis and that of cochlear otosclerosis resulting in clinically significant SNHL are unclear. The disease occurs in 8-10% of the White population; however, of those individuals affected, only 10-15% have clinical symptoms. Consequently, conductive hearing loss that necessitates treatment eventually develops in about 1% of the White population. Clinical disease occurs in about 0.5% of people of Asian and South American descent and in about 0.1% of those of African descent. The disease is bilateral in most cases.

For the vast majority of patients, the principal goal is remediation of hearing loss. Sodium fluoride has been used to arrest development of otosclerosis; although such therapy is now less common, it still has supporters. Hearing loss can be effectively remediated by using amplification. Most patients elect surgical repair. Surgery for otosclerosis is very successful, and more than 90% of patients experience complete elimination of conductive hearing loss. (See Treatment.)

For patient education resources, see the Ear, Nose, and Throat Center, as well as Tinnitus.

Next:

Pathophysiology

Two separate pathologic phases of the disease process can be identified:

  • Early otospongiotic phase
  • Later otosclerotic phase

The otosclerotic phase begins when osteoclasts are slowly replaced by osteoblasts and dense sclerotic bone is deposited in the areas of previous bone resorption. When this process involves the oval window in the area of the footplate, the footplate becomes fixed, resulting in conductive hearing loss. [4]  (See Histologic Findings.)

Previous
Next:

Epidemiology

Histologically, otosclerosis has a prevalence of about 10%. However, only about 10% of persons with histologic disease are clinically affected, and thus, the prevalence of clinically significant disease is about 1%. The most common morbidity from otosclerosis is hearing loss. [3] Although conductive hearing loss is considered the hallmark of the disease, involvement of portions of the otic capsule other than the stapedial footplate can result in SNHL. Rarely, patients may present with vertigo. [5]

Clinical otosclerosis can manifest as early as age 7-8 years but most commonly appears in persons aged 15-35 years. Women seek medical attention for hearing loss due to otosclerosis more frequently than men do. However, the disease is not sex-linked, and a histologic study of a large series of temporal bones shows no difference in prevalence between men and women. Otosclerosis is much more common in Whites than in persons of other races: Histologic otosclerosis occurs in 10-20% of Whites but in only about 1% of people of African descent.

Previous
Next:

Prognosis

The clinical progression of the disease is unpredictable. Bilateral involvement is typical, and, in most cases, conductive hearing loss progresses until the maximal 50-60 dB loss develops. SNHL can result in total deafness, but such severe progression is uncommon.

Previous