Recipient(s) will receive an email with a link to 'Otosclerosis (Otospongiosis)' and will have access to the topic for 7 days.
Subject: Otosclerosis (Otospongiosis)
(Optional message may have a maximum of 1000 characters.)
A primary bone dyscrasia involving the otic capsule
This is the leading cause of conductive hearing loss in adults.
There are two forms:
Histologic otosclerosis: asymptomatic form in which abnormal bone spares vital structures of the ear
Clinical otosclerosis: Abnormal spongy bone involves ossicular chain or other structures, leading to altered physiology.
System(s) affected: sensory, hearing
Clinical onset usually in early 20s
Peak incidence 3rd to 5th decade
Predominant gender: female > male (2:1)
Progression may accelerate during pregnancy.
Some women first notice hearing loss at this time.
Histologic form: 4–8% among U.S. Caucasian population; 1% among African Americans
Histologic form: U.S. Caucasian population: 5,000/100,000; African Americans: 1,000/100,000
Clinical form: 0.3–0.4%
Unknown; possible association with measles virus infection and hormonal factors
Fluoride metabolism may play a role; fluoride treatment is under investigation, as early results demonstrate improved hearing outcomes.
50–60% of those affected give positive family history.
Appears to be transmitted by autosomal dominant gene with variable expressivity
Van der Hoeve syndrome (rare triad of osteogenesis imperfecta, blue sclera, and otospongiosis)
Tinnitus, usually low frequency
Progressive conductive hearing loss, usually with well-preserved speech discrimination
Patients often are soft-spoken and aware that they seem to hear better in noisy environments.
Chronic suppurative otitis media
Serous otitis media
External auditory canal occlusion
Ossicular chain disruption
Congenital fixation of stapes
Paget disease of bone
Advanced otosclerosis mimics sensorineural deafness.
Will lateralize to more impaired ear with Weber test
Conductive hearing loss; may be as severe as the 60 dB maximum
May have sensorineural hearing loss with cochlear involvement
Carhart notch: a dip in bone conductive threshold at 2,000 Hz on audiometric testing
Off-white to reddish bone formation, most often located anterior to the oval window and extending to involve the stapedial footplate; sometimes covers entire oval window (obliterative); may be found anywhere in otic capsule
Bilateral in 75% of patients
Spongy-appearing bone with increased vascular spaces
Osteoblasts and osteoclasts are plentiful.
Important differential diagnosis for presbycusis
Surgical results similar in older versus younger patient cohorts (1)[A].
Surgical correction (stapedotomy/stapedectomy)
Usually involves mobilization or removal of the stapedial footplate with placement of a stapes prosthesis
Recent procedural innovations have involved use of lasers.
Cochlear implantation may achieve better results in advanced cases, but systematic reviews in 2014 and 2016 support initial stapes surgery with cochlear implantation reserved for those with unsatisfactory improvement in hearing and speech recognition (2,3,4)[A].
Hearing aids may be helpful postsurgery (5)[B].
Relative indications for surgery include negative Rinne test (air–bone audiometric gap at least 20 dB) and bilateral involvement.
No restrictions on activity
Because speech discrimination is usually preserved, patients should be advised of the possible benefit from hearing aids as an alternative or adjunct to surgery.
Mayo Foundation for Medical Education and Research, Section of Patient and Health Education, Sieber Subway, Rochester, MN 55905; (507) 284-8140
MedlinePlus. Otosclerosis: http://www.nlm.nih.gov/medlineplus/ency/article/001036.htm
Progressive hearing loss if not treated; 10% develop sensorineural hearing loss
Surgery closes air–bone gap to 10 dB in >90% of cases (6)[B].
Surgical results are durable in case series with >30 years of follow-up.
Some decline over time and may benefit from repeat surgical intervention.
Derks W, De Groot JA, Raymakers JA et al. Fluoride therapy for cochlear otosclerosis? An audiometric and computerized tomography evaluation. Acta Otolaryngol. 2001;121(2):174–177. [View Abstract]
Ealy M, Smith RJ. Otosclerosis. Adv Otorhinolaryngol. 2011;70:122–129. [View Abstract]
Marchese MR, Paludetti G, De Corso E et al. Role of stapes surgery in improving hearing loss caused by otosclerosis. J Laryngol Otol. 2007;121(5):438–443. [View Abstract]
Potocka-Bakłażec M, Sakowicz-Burkiewicz M, Kuczkowski J et al. Expression of TNF-α, OPG, IL-1β and the presence of measles virus RNA in the stapes of the patients with otosclerosis. Eur Arch Otorhinolaryngol. 2015;272(8):1907–1912. [View Abstract]
H80.90 Unspecified otosclerosis, unspecified ear
H80.20 Cochlear otosclerosis, unspecified ear
H80.00 Otosclerosis w oval window, nonobliterative, unsp ear
H80.10 Otosclerosis involving oval window, obliterative, unsp ear
H80.81 Other otosclerosis, right ear
H80.01 Otosclerosis w oval window, nonobliterative, right ear
H80.02 Otosclerosis w oval window, nonobliterative, left ear
H80.03 Otosclerosis involving oval window, nonobliterative, bi
H80.11 Otosclerosis involving oval window, obliterative, right ear
H80.12 Otosclerosis involving oval window, obliterative, left ear
H80.13 Otosclerosis involving oval window, obliterative, bilateral
H80.21 Cochlear otosclerosis, right ear
H80.22 Cochlear otosclerosis, left ear
H80.91 Unspecified otosclerosis, right ear
H80.80 Other otosclerosis, unspecified ear
H80.82 Other otosclerosis, left ear
H80.83 Other otosclerosis, bilateral
H80.93 Unspecified otosclerosis, bilateral
H80.92 Unspecified otosclerosis, left ear
H80.23 Cochlear otosclerosis, bilateral
387.9 Otosclerosis, unspecified
387.2 Cochlear otosclerosis
387.0 Otosclerosis involving oval window, nonobliterative
387.1 Otosclerosis involving oval window, obliterative
387.8 Other otosclerosis
11543004 Otosclerosis (disorder)
91108004 Cochlear otosclerosis
62856000 Nonobliterative otosclerosis involving oval window (disorder)
55664001 Obliterative otosclerosis involving oval window (disorder)
The audiometric signature of otosclerosis is a dip in conductive hearing at 2,000 Hz.
Hearing aids are helpful in patients with preserved speech discrimination.
Bilateral involvement and an air–bone audiometric gap of ≥20 dB are indications for surgery.
Surgical correction has a high success rate with good long-term durability.