Hypoacusia means a reduction in hearing ability. When hearing loss is profound, it is called deafness. Hearing loss, like deafness, may come either from the external ear, for example due to an excessive accumulation of earwax or malformations, or the middle ear as in some ear infections, a tumor, or an abnormality of the eardrum called otosclerosis. Other hearing impairments may be due to a problem with the inner ear caused by certain medications, infections such as mumps, or certain diseases like Meniere's disease. Certain disorders can affect the auditory nerve, such as neuroma or the progression of multiple sclerosis. To identify hearing impairment, hearing tests are performed.