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Learning the Lingo – Audiology Terminology

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Learning the Lingo – Audiology Terminology 9/2/2014 A Day In the life of Audiology… Learning the Lingo – Audiology Terminology Lori Garland, M.S., CCC-A, Pediatric Audiologist, Cincinnati Children’s Hospital Medical Center [email protected] Topics to Cover 1. Understanding Hearing Loss 2. Interpreting the Audiogram 1. 3. Tests to Evaluate Hearing 4. Types of Amplification 5. Specialized Evaluations Types of Hearing Loss 1. Conductive 2. Sensorineural 3. Mixed 4. Neural 5. Auditory Neuropathy Med El. (n.d.). Getting a Cochlear Implant. The Journey to Better Hearing. Retrieved from http://s3.medel.com/pdf/US/fl-br/20554_20_UCI+Brochure+USA.pdf 1 9/2/2014 Conductive Hearing loss Where hearing loss occurs… . Hearing loss in the outer and/or middle ear. Limits the ear from conducting sound properly . Inner ear is working normally. May be caused by middle ear fluid, perforation, of the ear drum, atresia, etc. Med El. (n.d.). Getting a Cochlear Implant. The Journey to Better Hearing. Retrieved from http://s3.medel.com/pdf/US/fl-br/20554_20_UCI+Brochure+USA.pdf Sensorineural Hearing Loss Mixed Hearing Loss . Combination of . Originates in the inner ear- conductive and in the cochlea or beyond. sensorineural hearing . Cochlea doesn’t function loss properly to transfer sounds . Involvement of inner to the auditory nerve and outer/middle ear . Typically permanent . May be due to disease . Connexin 26, genetic, state CHARGE, etc. May benefit with hearing aids Med El. (n.d.). Getting a Cochlear Implant. The Journey to Better Hearing. Retrieved from http://s3.medel.com/pdf/US/fl-br/20554_20_UCI+Brochure+USA.pdf Auditory Neuropathy Spectrum Neural Hearing Loss Disorder . Loss that involves the transmission of the auditory signal to the . Damage to or absence of auditory nerve brain . Typically a profound permanent hearing loss . Characteristics include poor speech perception and poor performance in the presence of background noise: present . Hearing aids and cochlear implant will not help OAEs, cochlear microphonic with absent or abnormal ABR . Outer hair cells function properly while damage may exist in the inner hair cells – ranging from normal hearing to severe hearing loss . May be linked to hyperbilirubinemia, prematurity, conditions with neural dysfunction (e.g. CP) . Outcomes vary - may benefit from hearing aids, personal FM or cochlear implant Med El. (n.d.). Getting a Cochlear Implant. The Journey to Better Hearing. Retrieved from http://s3.medel.com/pdf/US/fl-br/20554_20_UCI+Brochure+USA.pdf 2 9/2/2014 Degrees of Hearing Loss Degree: Impact: 0-15dB 2. Source: Clark, J. G. (1981). Uses and abuses of hearing loss classification. Source: www.successforkidswith hearing Asha, 23, 493–500. loss.com Audiogram Breaking Down the Audiogram The audiogram is separated into frequency and loudness levels. The unit of frequency is measured in cycles per second and is called hertz(Hz). Hearing is NOT measured in percentages but rather in units of loudness called the decibel (dB). http://uknewbornhearing.yolasite.com/how-we-hear.php http://www.jtc.org/parents/ideas-advice-blog- comments/audiogram-of-familiar-sounds Tones versus Speech Terms on the Audiogram SRT – speech reception threshold Tonal thresholds: Speech Testing: the intensity at which an individual can identify simple . Provides information on softest . Provides information on speech materials approximately 50% of the time levels detected by a patient patient’s ability to detect and WRS- word recognition score across a range of frequencies recognize speech information Optimal performance on word recognition under . Graph used to compare hearing . Useful for determining controlled conditions thresholds across time appropriate amplification Used to compare to follow up tests and assist in . Configuration of audiogram . Best predictor of benefit with amplification recommendations assists in predicting audibility of amplification PTA - puretone average speech sounds at different . More relatable to real world frequencies than tonal information Average of puretones at 500Hz, 1kHz, 2kHz Used to compare to speech scores and audiogram Masking – noise in the non-test ear used for both air and bone conduction testing to ensure the non-test ear (cochlea) is not responding 3 9/2/2014 More Terms… Is the Aided Audiogram Useful? OAE – otoacoustic emissions Sounds emitted by the outer hair cells in the inner ear when the Cochlear Implant Hearing Aid cochlea is presented a sound Present for hearing ≤ a mild hearing loss Often used for newborn hearing screenings Reflexes – acoustic reflexes A reflex occurs when a signal is transmitted causing a contraction of the stapedius muscle tissue, below the level of cognitive control Useful in determining a site of lesion since the response occurs in both ears CPA – conditioned play audiometry VRA –visual reinforcement audiometry BOA – behavioral observation audiometry To Mark or Not to Mark? Many differing opinions on the use of aided testing with tonal stimuli Responses do NOT represent functional hearing ability Represent perception of tonal stimuli – Hearing aids have advanced features that may be detect the sounds as “noise” and alter the response – Newer technology is designed to recognize the patterns of speech – not amplify puretones or narrowband noise – Many practices have eliminated the use of aided audiograms to avoid misinterpretation of child’s auditory ability and replaced with aided speech tests and real ear measurements – Aided speech testing is a more accurate representation of patient’s access to sounds Types of Tests: . ABR – Auditory Brainstem Response Testing Auditory Brainstem Response Test (ABR) . DPOAEs – Distortion Product Otoacoustic Electrical impulses are transmitted through nerves from our Emissions ears to the brainstem . Tympanometry Tests the integrity of the hearing system from the ear to the . Acoustic Reflexes brainstem. Behavioral Testing As the hearing nerve fires, the sound stimulus travels up to . Children the brain. This electrical activity can be recorded by the electrodes and is represented as waveforms on a computer . Babies screen. Older patients . Aided Speech Testing Patient must be sleeping or very quiet http://farm3.staticflickr.com/2860/10846031566_c17f4945f6_o.jpg 4 9/2/2014 ABR Testing Distortion Product Otoacoustic Emissions (DPOAEs) An otoacoustic emission test (OAE) measures an acoustic response that is produced by the outer hair cells in the cochlea, which in essence bounces back out of the ear in response to a sound stimulus. As the patient sits quietly, sounds are generated in the probe. DPOAEs Tympanometry an objective test of middle-ear function used to test the condition of the middle ear, mobility of the eardrum and the ossicles by creating variations of air pressure in the ear canal Tympanometry Acoustic Reflex Pathway Indicated with the following - . vertigo, tinnitus, sudden hearing loss, suspect faking hearing loss; newly identified hearing loss Purpose – . Contribute to evaluation of middle ear, cochlea and innervation of stapedius muscle Normal – . Involuntary response from the stapedius muscle to loud sounds Type A = normal Abnormal – Type B = Flat . May suggest presence of a Type C = negative ME pressure retrocochlear pathology Type As = shallow compliance . Small intra-axial pathology Type AD = hypercompliance 5 9/2/2014 Behavioral Testing (Infants) Behavioral Testing (Infants/Children) Visual Reinforcement Behavioral Observation Audiometry (BOA) Audiometry (VRA) . Used for infants and patients with significant physical or mental . infant-2 ½ years or when patient delays has developmental delays- may or may not get ear-specific . Observe changes in behavior to presented sounds thresholds . May be a change in sucking, expression or eye gaze – does not determine hearing thresholds http://www.medicinenet.com/detecting_hearing_loss_in_children/page3.htm Conditioned Play Audiometry (CPA) . 2- 5 years - conditioned to play a game when they hear a sound – typically get ear- specific thresholds http://www.medicinenet.com/detecting_hearing_loss_in_children/page3.htm VRA with earphones Bone conduction testing Masking for bone conduction testing Testing Older Patients Aided Speech Perception Testing American Speech Hearing Language Association’s (ASHA) recommended set-up www.asha.org 6 9/2/2014 Speech Tests Tests by Age/Developmental Ability • Ling 6 sound: /m/, /oo/, /sh/, /ah/, /s/, /ee/ • Aided SRT, WRS (at 50 dB HL and 35 dB HL) Age Tests • Speech in noise testing < 6 months ABR, bone conduction through ABR, OAE, tympanometry, • Aided testing with sentences > 6 months – 2½ VRA, bone conduction, OAE, tympanometry, earphones when • Aided testing for each ear separately as well years possible as binaurally 2 ½ years – 5 CPA, bone conduction, OAE, tympanometry, reflexes when • Real Ear Measurements (REM) years needed; ear-specific – Real ear performance of hearing aids using a probe microphone in ear with speech passage (LTASS) > 5 years Press button or raise hand, bone conduction, OAE, – Determine if soft, average and loud speech sounds tympanometry, reflexes when necessary; always ear specific – are audible for patient’s hearing loss if capable, developmentally – Does not rely on patient’s responses – Affected by condition of ear canal and middle ear Devices: . Traditional Hearing aids . Bone conduction devices . CROS/BiCROS amplification . Cochlear Implants . FM systems Traditional Hearing aid Earmolds • Earmold impressions • Swimmolds • Hearing aid earmolds 7 9/2/2014 Hearing aid styles Bone conduction devices www.ent.uci.edu
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