Conductive Hearing Loss
Conductive hearing loss occurs when sound is not conducted efficiently throught the outer ear canal to the eardrum and the tiny bones, or ossicles, of the middle ear. Conductive hearing loss usually involves a reduction in sound level,or the ability to hear faint sound.
Sensorineural Hearing Loss
Sensorineural hearing loss occurs when there is damage to the inner ear (cochlea) or to the nerve pathways from the inner ear to the brain. Sensorineural hearin loss cannot be medically and surgically corrected. It is a permanent loss. Sensorineural hearin loss not only a involves reduction in sound level, or ability to hear faint sounds, but also affects speech understanding, or ability to hear clearly. Senorineural hearing loss can be caused by diseases, birth injury, drugs that are toxic to the auditory system and genetic syndromes. Sensorineural hearing loss may also occurs as a result of noise exposure, viruses, head trauma, aging and tumors.
Mixed Hearing Loss
Sometimes a conductive hearing loss occurs in combination with a sensorineural hearing loss. In other words,there may be damage in the outer or middle ear and in the inner ear (cochlea) or auditory nerve. When this occurs, the hearing loss is referred to as a mixed hearing loss.