Hearing loss is not an all-or-nothing proposition but rather must be measured on a continuous scale. Moreover, it is not simply a one-dimensional scale that measures loudness; audiologists testing for hearing loss also consider whether a person can hear equally well at different sound frequencies. Finally, an audiologist must consider how any hearing loss affects a person's daily life in order to recommend the most helpful course of treatment.
One of the very first determinations that an audiologist or other clinician must make when presented with someone who believes that he or she is suffering hearing loss is to determine what degree of hearing loss may be present. Hearing loss may range from non-existent to mild (27-40dB) to profound (above 90 dB) (Van Hattum 113). Once an audiologist has determined that hearing loss has occurred, she or he must next determine whether the condition is due to conductive or sensorineural conditions, the two most common forms of hearing loss. To assess which condition affects the patient in this question – Mr. Brown – several factors must be determined.
Conductive hearing loss is diagnosed when there is a problem in the outer or middle ear. Common reasons for conductive hearing loss are a build-up of ear wax, a foreign object stuck in the outer part of the ear, or the hereditary disease of otosclerosis in which two inner-ear bones are locked together preventing vibrations from reaching the fluid in the inner ear (Emerick 144-5).
Conductive hearing loss can be recognized by a number of salient features, including the fact that loss of hearing acuity rarely exceeds 60 dB and the individual hears well at all frequency levels. Finally, the individual hears better by bone conduction (through the bones of the head) than by air conduction (Emerick 145).
If Mr. Brown should found to be suffering from a hearing loss in this decibel range added to the key finding of equal hearing loss in all fre...