Certain features of a patient's hearing loss can help identify the probable type.
Types of hearing loss:
(1) conductive: lesions of the external (cerumen, etc.) or middle (otitis media, otosclerosis, etc.) ear
(2) sensorineural: lesions to the cochlea, auditory division of the acoustic nerve, or both
(3) central: lesions of the central auditory pathways (cochlear and dorsal olivary nuclear complexes, inferior colliculi, medial geniculate bodies, auditory cortex in the temporal lobes, and interconnecting afferent and efferent fiber tracts.
Feature |
Conductive |
Sensori-neural |
Central |
helped by loud speech |
yes |
no |
no |
helped by a quiet background |
no |
yes |
yes |
may be unilateral |
yes |
yes |
no |
affects certain frequencies only |
no |
yes |
no |
Conductive hearing loss:
(1) loud speech can be readily understood
(2) patients can hear speech in a noisy background better than in a quiet background
Sensorineural hearing loss:
(1) the hearing levels for different frequencies are usually unequal
(2) patients may have difficulty hearing speech if there is background noise present
(3) patients may be annoyed by loud speech
Central hearing loss:
(1) hearing of pure tones not impaired
(2) speech understood if it is clearly spoken in a quiet environment
(3) comprehension markedly deteriorates if there is background noise or competing messages
Specialty: Neurology, Otolaryngology
ICD-10: ,