Hearing loss types
Conductive HL caused by damage to any mechanical components of the ear, eg accumulation of cerumen, disruption of tympanic membrane, fusion of one or more middle ear ossicles; conductive HLs may be amenable to surgery
Sensorineural HL due to a defect in the neural pathways, which may be at the level of the cochlea, auditory nerve, or in the cerebral cortex Etiology Infections–especially intrauterine, eg rubella, drug toxicity, eg aminoglycosides, and tumors, eg acoustic neuroma
Mixed HL due to a combination of mechanical and neural defects Etiology Down syndrome, cystic fibrosis, cerebral palsy