deafness is classified as either conductive or sensorineural hearing loss / deafness or mixed and these are generally differentiated at the bedside by using Rinne and Weber tuning fork tests:
Rinne test:
place tuning fork on the mastoid bone behind the ear (tests bone conduction (BC)).
when the patient indicates sound is no longer heard, move fork (held at base) beside ear and ask if now audible.
in a normal test, AC > BC; patient can hear fork at ear.
in conductive loss, BC > AC; patient will not hear fork at ear
Weber test:
tuning fork is placed in middle of forehead
normal person should hear it equally in both ears
hearing it best in one ear implies either:
conductive loss in THAT ear, or,
sensorineural loss in the OPPOSITE ear
in addition, hearing loss may be due to a central cause such as from a stroke (CVA) or present as auditory dyssynchrony (auditory neuropathy or auditory neuropathy spectrum disorder)