Conductive hearing loss is caused by a range of developmental, congenital or acquired pathology to the external, middle or inner ear.
Essentially any process that obstructs or disrupts the passage of sound waves through the outer or middle ear can cause conductive hearing loss and the list of causes is very long. The most common are included below.
- Cerumen (earwax) or external auditory canal foreign body
- congenital, e.g. external acoustic canal (EAC) atresia
- trauma, e.g. tympanic membrane perforation (not seen radiologically)
- otitis externa
- external auditory canal benign lesions, e.g. osteoma, exostosis, keratosis obturans and medial canal fibrosis
- external acoustic canal tumours, e.g. cholesteatoma, squamous cell carcinoma
- barotrauma (unequal air pressure in the external and middle ear)
- congenital, e.g. congenital ossicular fixation
- trauma, e.g. ossicular chain disruption
- inflammatory, e.g. otomastoiditis
- middle ear tumours, e.g. glomus tympanicum, cholesteatoma, middle ear schwannoma
- Eustachian tube dysfunction
- congenital, e.g. oval window atresia (rare)
- fenestral otosclerosis
- superior semicircular canal dehiscence syndrome
Treatment and prognosis
A stapes prosthesis may help improve conductive hearing loss.
- 1. Wippold FJ, Turski PA. Vertigo and hearing loss. AJNR Am J Neuroradiol. 2009;30 (8): 1623-5. AJNR Am J Neuroradiol (full text) - Pubmed citation
- 2. Mirvis SE, Soto JA, Shanmuganathan K et-al. Problem Solving in Emergency Radiology: Expert Consult - Online. Saunders. ISBN:B00N04AZQC. Read it at Google Books - Find it at Amazon
- 3. Ferri's Clinical Advisor 2015. Mosby. ISBN:0323083757. Read it at Google Books - Find it at Amazon
- 4. Zeifer B, Sabini P, Sonne J. Congenital absence of the oval window: radiologic diagnosis and associated anomalies. AJNR Am J Neuroradiol. 2000;21 (2): 322-7. AJNR Am J Neuroradiol (full text) - Pubmed citation