International Licensing Examination (ILE) Practice Test

Which condition may lead to a conductive hearing loss due to issues with the transmission of sound in the middle ear?

1. Ossicular fixation

2. Tympanosclerosis

3. Acoustic neuroma

4. Cholesteatoma

The correct answer is: Ossicular fixation

The condition that primarily leads to conductive hearing loss due to problems with sound transmission in the middle ear is ossicular fixation. This refers to the immobilization of the ossicles, which are the tiny bones in the middle ear responsible for transmitting sound vibrations from the eardrum to the inner ear. When these bones become fixed due to conditions like otosclerosis, they cannot effectively vibrate, which impairs sound transmission and results in conductive hearing loss. While tympanosclerosis, acoustic neuroma, and cholesteatoma can also affect hearing, they do so in different ways. Tympanosclerosis typically involves the thickening or scarring of the tympanic membrane (eardrum) and might affect sound transmission but does not usually cause fixation of the ossicles itself. Acoustic neuromas are tumors on the vestibulocochlear nerve and are more associated with sensorineural hearing loss than conductive loss. Cholesteatoma, which is an abnormal skin growth in the middle ear that can lead to erosion of structures, can cause conductive hearing loss, but the mechanism is more related to destruction rather than pure fixation of the ossicles. Thus, ossicular fixation remains the most direct cause of conductive hearing loss due to compromised transmission of sound