Anything that prevents sound waves from being transmitted to the inner ear may result in a conductive hearing loss. Conductive loss may result from
- blockage of the external auditory canal e.g. earwax, beads
- damage to the eardrum e.g. perforated eardrum
- damage to the middle ear e.g. blockage of the Eustachian tube , infection of the middle ear, damage to the ossicular chain(the three tiny bones in the middle ear)
Middle ear infection is the most common cause of a conductive loss in young children. The middle ear cavity is normally filled with air but it may become infected when infections of any kind from the throat or the nose travel up through the Eustachian tube. In some cases, thick mucus (glue ear) may build up and restrict the movement of the eardrum and the middle ear ossicles. Usually antibiotics and decongestants are prescribed but if fluid persists, a tiny tube into the eardrum can be inserted to drain the fluid and ventilate the middle ear.