HISTORY OF HEARING TESTING

Audiology

Audio - Latin…to hear, pertaining to hearing Logy - Greek…logus…science Therefore the science of hearing and hearing

disorders

Facets of audiology

Discovery Evaluation Rehabilitation

Lineage of Audiology

Originated during and just after WW II (1945-46)

Originally audiologists were SLP’s or ENT’s Father of Audiology is Raymond Carhart (he

and Norton Canfield coined the term “audiology

Reason for the field of Audiology The government became concerned with hearing disorders

when VA hospitals had military with hearing problems due to:-direct injury—gunshot, shrapnel -disease—jungle rot-acoustic trauma—high intensity noise (cannons,guns,etc)-emotional disorders - “shell shock” (protective device)

Aural rehabilitation hospitals opened all over the nation and were interested in:

-conservation of hearing-habilitation and rehabilitation programs-diagnosis (Dx) of hearing loss related to medical problems-educational placement and programs for the hearing impaired

Academic Qualifications for Audiologist BA/BS in Communicative Disorders or equivalent MA/MS in Audiology Pass national written examination (formerly NESPA) Complete Clinical Fellowship Year (CFY) Certificate of Clinical Competence in Audiology

(CCCA) State License (usually CCCA + fees) Au.D. or equivalent will be needed by 2007 Ph.D. and FAAA is optional at this time

Other Hearing Health Professionals Otolaryngologist Hearing Conservationist Hearing Aid Specialist Audioprosthologist Audiometrist

Professional Opportunities for Audiologists

Teaching Clinical Research Administration

Hearing Tests and their Development (non-audiometric)

Watch tick Coin-click Conversational voice Noise makers Tuning fork tests (Demonstrate using tuning fork)

Schwabach Test (also called the time threshold test) Rinne Test Bing test Weber

Pure Tone Audiometry

Normal hearing (intensity) = 0—25dB (ANSI) We hear 20—20,000 Hertz (frequency) We only test 250—8,000 Hertz (Hz) 250, 500, 1000, 2000, 3000, 4000, 6000 & 8000Hz are the

individual frequencies at which we test by AC 250, 500, 1000, 2000 and 4000Hz are the frequencies for BC Quiet environment needed (otocups, insert phones and booths Occlusion effect—the increase of loudness of pure tones at 1000

Hz or lower. Happens in normal, sn—not in conductive losses. Sweep check vs. threshold testing

Otoscope

Performing the Pure Tone Test Check calibration of audiometer Otoscopic inspection (wax, collapsed canal,

drainage etc.) Patient instructions Question: Which is your better ear? Hairdos, wigs, glasses and earrings Correct placement of earphones (TDH 39) Correct placement of the patient

Performing the Pure Tone Test (continued)

Pulsed or continuous signal Present tone with about 1 second duration Be aware of eye contact Watch out for “rhythm system” Red, right, round. Blue X’s for left (AC) Bone conduction (BC) thresholds and

symbols Masking for AC and BC Maximum output at each frequency

Patient Responses

False negative False positive Validity vs. reliability Down 10; up 5 rule Determine threshold Test re-test reliability Pure tone average (PTA) Tactile responses (cutile) Cross hearing and interaural attenuation (IA) AC & BC

Masking

Narrow band White noise (broad band or wide band noise) Effective masking Over masking (OM Speech noise Complex noise Other masking (saw tooth, pink noise etc.) Plateau Method

Calculation of Percentage of Hearing Loss Average thresholds at 500, 1K, 2K and 3KHz Subtract 25 dB Multiply X 1.5 for each ear = % of loss per

ear Binaural loss %’age = better ear X 5 + poorer

ear %age divided by 6 = binaural percentage loss

Audiograms

Table audiogram Graph audiogram