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Methods for assigning impairment
Published in Ramar Sabapathi Vinayagam, Integrated Evaluation of Disability, 2019
Pure tone audiometry evaluates hearing impairment. Audiometry delivers sounds of specific frequencies, that is, 125, 250, 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz at different intensities with earphones for air conduction for measuring hearing thresholds. It delivers 125, 250, 500, 1000, 2000, 3000, 4000 Hz with oscillator held at mastoid or forehead for bone conduction by audiometer for measuring hearing thresholds. The threshold for normal hearing is 0 ± 10 dB.
The Role of the Audiologist in Life Care Planning
Published in Roger O. Weed, Debra E. Berens, Life Care Planning and Case Management Handbook, 2018
William D. Mustain, Carolyn Wiles Higdon
Pure tone audiometry is performed to determine if hearing is normal or impaired. An audiologist, using a calibrated electronic device, called an audiometer, and standardized procedures, measures hearing sensitivity. The individual being tested initially wears earphones and the audiologist presents tones of varying frequencies and intensities to each ear. When the individual hears the tone, they respond by raising their hand or pressing a response button. The lowest intensity level at which the tone is heard two out of three times is called threshold. This process is then repeated with the individual wearing a bone vibrator placed on the mastoid bone. When thresholds using earphones are outside the normal range, a comparison with the bone vibrator thresholds will indicate which part of the auditory system is responsible for the hearing loss.
Physiology of Hearing
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Soumit Dasgupta, Michael Maslin
The bandwidth of human hearing (at least for a young person with normal hearing) is typically from around 0.02–20 kHz. Vibrations of around 20 times per second correspond to a low pitch whereas vibrations of 20 000 times per second correspond to a much higher pitch. Each time the frequency of a sine wave is doubled, the pitch increases by an octave, so human hearing spans around 10 octaves. A sound which has one frequency is known as a ‘pure tone’ although, in reality, typical sounds are made up from many frequencies and are therefore complex sounds.
Open-angle Glaucoma and Sensorineural Hearing Impairment in the Korean Population
Published in Current Eye Research, 2020
Joon Mo Kim, Mi Yeon Lee, Jong Woo Kim, Jungmin Lee, Hyun Ji Kim, Soon Cheol Cha, Na Rae Kim
Ear examinations were performed using a 4-mm 0-angled rigid endoscope (Xion GmbH, Berlin, Germany) and the ML 150 vision system (JRMed Trade Co., Seoul, Korea) by otolaryngologists and otolaryngology residents who were trained annually. The examination data were periodically evaluated by the committee for quality control. Air-condition pure-tone thresholds were measured in a double-walled soundproof booth (CD-600; Sontek, Paju, Korea) by using an automatic audiometer (GSI SA-203; Entomed Diagnostics AB, Lena Nodin, Sweden) for each ear at six frequencies (500, 1000, 2000, 3000, 4000, and 6000 Hz) by well-trained examiners. Hearing loss was defined as the pure-tone average of thresholds at 500, 1000, 2000, 3000, 4000, and 6000 Hz, with an average of both ears greater than the 40-dB hearing level. Hearing impairment was categorized according to frequency (low or high) and severity (mild or moderate-to-profound). Low-frequency pure-tone means were defined by averaging the pure-tone thresholds measured at 500, 1000, and 2000 Hz. High-frequency pure-tone means were defined by averaging the pure-tone thresholds measured at 3000, 4000, and 6000 Hz. Mild hearing impairment was defined as an unaided pure-tone mean of 26–40 dB. Moderate-to-profound hearing impairment was defined as an unaided pure-tone mean > 40 dB.
Hearing thresholds and cognitive flexibility in young healthy individuals with normal hearing
Published in International Journal of Audiology, 2020
K. Jonas Brännström, Tobias Kastberg, Sebastian Waechter, Elisabeth Karlsson
It is not obvious why cognitive flexibility is related to hearing thresholds. Pure tone audiometry is a detection task where the participant is instructed to press a button every time a tone is heard. The participant thus needs to decide whether a signal is present or not before responding. Arguably, all three core executive functions may be involved to complete this task (Diamond 2013); Working memory seems required to maintain short-term goals in task goal pursuit (press the button when a signal is detected). Inhibitory control seems required to inhibit behaviour (withholding response when there is no signal). Cognitive flexibility seems required to be able to change perspective and switch between tasks (decide whether a signal is present or not) (Diamond 2013). These findings suggest that the ability to change perspective and/or switch tasks could be important when engaging in pure tone audiometry. On the other hand, it is also possible that a common source of error is present when testing both pure tone audiometry and cognitive flexibility, i.e. an unknown factor influencing performance in all these tests in a common way, causing the correlation. It is also possible that pure tone audiometry is not a demanding task as long as the signals are clearly audible. As soon as we approach threshold and tones are presented in the vicinity of what is physiologically possible to detect, perhaps those with higher cognitive capacity can push themselves further in order to make accurate decisions, i.e. whether a tone is present or not.
Different prognoses in patients with profound sudden sensorineural hearing loss
Published in Acta Oto-Laryngologica, 2019
Fan-Qin Wei, Lanying Wen, Kaitian Chen, Min Liu, Xuan Wu
Cochlear and vestibular functions were examined before and after treatment. The pure tone average threshold was determined by calculating the mean hearing threshold frequencies (0.5, 1, 2, and 4 kHz). A word recognition score (WRS) was obtained by speech audiometry (0%–100%). The results of positioning and caloric tests were documented with videonystagmography. Dix-Hallpike and Roll tests were used to diagnose vertical and horizontal semicircular canal benign paroxysmal positional vertigo (BPPV). The caloric tests were performed using a bithermal sequential caloric air irrigator (ATMOS, Germany) while recording eye movements using an infrared video-based system (Ulmer VNG, v.1.4; Synapsys, Marseille, France). Each ear was irrigated alternately with a constant flow of air at 24 °C and 50 °C for 40 seconds. The maximum slow-phase velocity (SPV) of nystagmus was calculated following each irrigation, and Jongkees’ formula was used to determine canal paresis (CP). A CP value ≥ 25% was considered abnormal.