Hearing is the sensing of sound vibrations in the air. When a sound occurs (people speaking, doorbell, birds chirping, music) it produces a vibration that travels through the air displacing it. The displaced air is called a sound wave. Sound waves are collected by the outer ear and delivered to the ear drum to vibrate. This vibration in turn sets the three tiny bones (ossicles) of the middle ear in motion, transferring the ear drum vibrations to the inner ear (cochlea). Thousands of hair cells lining the inside of the cochlea move in response to this displacement. When the hair cells "bend", they send neural impulses along the hearing (auditory) nerve to the brain (cerebral cortex) where these impulses are perceived as "sound".

Problems occurring anywhere along the hearing chain, from the outer ear to the brain, can produce a hearing loss. Usually hearing loss is either conductive or sensorineural. Occasionally it can be a combination of both (mixed hearing loss).

TYPES OF HEARING LOSS:

Click on each of the following types of hearing loss to learn more about it:
CONDUCTIVE HEARING LOSS
SENSORINEURAL HEARING LOSS
MIXED HEARING LOSS

Results of the audiometric evaluation are plotted on a chart called an audiogram. Loudness is plotted from top to bottom. Frequency, from low to high, is plotted from left to right. Hearing loss (HL) is measured in decibels (dB) and is described in general categories. Hearing loss is not measured in percentages. The general hearing loss categories used by most hearing professionals are as follows:

Normal hearing (0 to 25 dB HL)
Mild hearing loss (26 to 40 dB HL)
Moderate hearing loss (41 to 70 dB HL)
Severe hearing loss (71 to 90 dB HL)
Profound hearing loss (greater than 91 dB HL)

First, a physician specializing in disorders of the ear must determine the type of hearing loss you have. The type of hearing loss can only be determined through microscopic examination of your ears and a thorough audiometric test (a hearing test that includes testing with pure tones through both air and bone conduction, speech testing, and middle ear pressure tests). Once a diagnosis has been made, treatment can be decided.

Nearly all types of conductive hearing losses can be repaired with surgery. Dr. Slater specializes in innovative surgical techniques to repair conductive hearing loss. Do not become discouraged if you have had previous surgery to repair your hearing and it was unsuccessful. Many patients have had their hearing successfully restored even though they had undergone one or more previous unsuccessful operations prior to referral to my clinic.

Sensorineural hearing losses caused by a loss of hair cells can only be improved with modern hearing aids. Many patients with this type of hearing loss come to the Austin Clinic because they are dissatisfied with their present hearing aids. Dr. Slater specializes in fitting such individuals with the new generation of hearing aids or the new implantable hearing device from Soundtec. In the past couple of years, hearing aids have been developed that process sound digitally much the same way that a computer processes information. This allows for infinite programming possibilities which make the sounds coming through the hearing aid sound more natural and which provides better clarity for speech both in quiet and noise (see hearing aids).