Diagnostic Audiology Complete Audiological Evaluation Case History Otoscopy Immittance Testing Determine Degree of h. loss Determine Type of h. loss Speech Testing Counseling Recommendations Why here? Maybe failed a screening at school, work, dr office or public health screening or maybe never screened but feel there is a problem or family member suggested, follow up for known h. loss

Case History Complaints and symptoms Self assessment of hearing Attributed cause of HL if suspected Medical history Rehabilitative history Goal of visit Why here? Maybe failed a screening at school, work, dr office or public health screening or maybe never screened but feel there is a problem or family member suggested, follow up for known h. loss Ask individual to describe their hearing ability. Do you have trouble hearing on the telephone? Do you hear the same in both ears? Symptoms other than hearing loss §         Do they complain of dizziness (vertigo)? (Vestibular system) §         Do they experience a ringing in the ear (tinnitus)? Causes of Hearing Loss Illness that might have caused hearing loss Other circumstances that might have caused HL Rehabilitation Do they wear a hearing aid? What do they use

Otoscopy Pull pinna up and back Check external auditory meatus Check tympanic membrane and middle ear landmarks (e.g., cone of light, malleus) ·        ·        Look for healthy Tympanic Membrane (cone of light, shadow of the malleus, and some cerumen (wax)) ·        Check for impacted cerumen, foreign objects or other obstructions of the External Auditory Meatus Check for collapsed ear canal- when the earphone is on the ear it puts pressure on the pinnea, which in turn puts pressure on the wall of the EAM causing it to close. In this exam press on pinnea and observe EAM

Pure tone Audiometry Factors Affecting Threshold of Hearing Methodological factors Physiological factors Psychological factors Physical factors Environmental factors

Pure tone testing Instructions Set-up You will be hearing a tone. Respond when you hear it or you think you hear it Set-up Seating – front/back/side facing Earphones – standard or insert Response mode – finger/hand, verbal, button

Air Conduction Audiometry Goal: Determine the degree (amount) of HL from the outer ear and on Combined effects of conductive and sensorineural HL

Diagnostic Audiology Determining type (location) of HL Conductive (outer &/or middle ear) Sensorineural (inner ear &/or 8th nerve) Sensory (inner ear) vs. neural (8th nerve) Sensory Pathology can be called cochlear or inner ear pathology Neural pathology can be called retrocochlear or 8Th nerve pathology Mixed hearing loss (conductive & SN) peripheral (outer ear through 8th nerve) vs. central (from brainstem through cortex)

The Audiogram is a graphical representation of hearing Plots frequency/pitch vs. intensity of sound. Generally shows responses of both ears to sound presented through an earphone and through a bone oscillator

Audiogram

Speech Banana This audiogram demonstrates where speech sounds and various environmental sounds would be represented on an audiogram. The yellow, banana-shaped figure represents sounds that make up the human voice when speaking at normal conversational levels

Frequency/Pitch Vertical lines on an audiogram represent pitch or frequency. The 125 Hertz (Hz) vertical line on the left side of the audiogram represents a very low pitch sound and each vertical line to the right represents a higher pitch sound. Moving from left to right on the audiogram is similar to moving from left to right on a piano keyboard. The central frequencies of 500-3000 Hz are generally considered to be the most important for speech comprehension.

Intensity/Loudness Horizontal lines represent loudness or intensity. The 0 decibel (dB HL) line near the top of the audiogram represents an extremely soft sound. Each horizontal line below represents a louder sound. Moving from the top to the bottom would be consistent with hitting the piano key harder or turning up the volume control on your sound system (radio, tv, IPod, etc.).

Audiogram Explanation Therefore, every point on an audiogram represents a different sound. Point A on the audiogram to the right represents a soft low-pitch sound Point B represents a soft high-pitch sound Point C represents a loud mid-pitch sound.

Threshold The softest sound you are able to hear at each pitch (the “threshold”) is recorded on the audiogram. Thresholds of 25 dB and smaller in magnitude are considered normal (for adults). The audiogram on the right demonstrates the different degrees of hearing loss.

Air Conduction Testing   Place a dot at that threshold, then test 2k Hz, 4kHz, 8kHz, recheck 1k Hz and make appropriate mark, 500 Hz, and 250 Hz ·    If there is a 20 dB difference between two adjacent test frequencies, check the interoctave freq. Test better ear first

Air Conduction Testing  * Set audiometer frequency at 1000 Hz at an intensity of 30 dBHL and present that signal to the better ear  * If the client responds decrease tone by 10 dB.  If the client doesn’t not respond, increase tone by 5 dB (Hughson Westlake Procedure) * The lowest level of intensity that the client responded to 50% of the time is their air conduction threshold

Air Conduction Testing O = right AC threshold, X = left AC Summarize findings Pure tone Average (PTA) Three frequency (500, 1k, 2k) Two frequency (2 best frequencies from above 3) Degree of communication impact Mild (26-40 dBHL) Moderate (45-55dBHL) Moderately-severe (56-70dBHL) Severe (71-90dBHL) Profound (>90dBHL)

Audiograms

Degree of Hearing Loss Minimal Mild Moderate Moderately Severe Severe Profound

Mild HL (26-40dBHL) Consideration of need for hearing aid Adults will have difficulty with soft speech (30dB HL), but often able to compensate via speech reading, redundancy and context of language Children: language learning difficulty and articulation issues

Moderate HL (45-55dBHL) Hearing aids often beneficial Difficulty noted by adults at normal conversational levels (50dBHL) Children would experience significant language learning dysfunction

Moderately-Severe HL (56-70 dBHL) No speech sounds audible at normal conversational levels (50dBHL) Hearing aids typically beneficial

Severe HL (71-90 dBHL) Difficulty hearing even loud speech (70 dBHL) without amplification Hearing aids or cochlear implants may be beneficial

Profound HL (91dBHL+) Hearing aids may be of benefit Visual cues very important Might be a candidates for cochlear implant Typically referred to as ‘deaf’, but may have some residual hearing

Hearing Loss Simulation Some interesting websites exist: http://facstaff.uww.edu/bradleys/radio/library.html http://www.hearingcenteronline.com/sound.shtml http://www.neurophys.wisc.edu/animations/ http://www.cdc.gov/niosh/mining/topics/hearingloss/hlsoundslike.htm