Ebook Audiology science to practice (3E): Part 2
➤ Gửi thông báo lỗi ⚠️ Báo cáo tài liệu vi phạmNội dung chi tiết: Ebook Audiology science to practice (3E): Part 2
Ebook Audiology science to practice (3E): Part 2
9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2ed in some cases in order to obtain true thresholds in the test ear (TE).2Know what is meant by interaural attenuation (IA) and the minimum IA values used for each transducer when making decisions about the need to obtain masked thresholds.3Recognize, from the unmasked thresholds, when masked thresh Ebook Audiology science to practice (3E): Part 2olds must be obtained: apply the decision-making rules for masking when testing by air conduction (AC) using supra-aural earphones or insert earphonesEbook Audiology science to practice (3E): Part 2
and by bone conduction (BC).4Describe the types of maskers used for pure-tone and speech testing.5Define effective masking (EM) and how the maskers a9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2dvantages of insert earphones over supra-aural earphones as they relate to masking.8Define what Is meant by a masking plateau and how much of a plateau is appropriate. Discuss why the width of the plateau IS smaller when there IS a potential bilateral moderate conductive loss.9Define overmasking and Ebook Audiology science to practice (3E): Part 2 masking dilemma, and recognize situations in which these may occur.10Apply the specific steps for AC and BC masking using the plateau method for a vaEbook Audiology science to practice (3E): Part 2
riety of unmasked audiograms.11Apply the rules for determining if masking is needed for speech testing, and select adequate amounts of maskers for spe9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2es from the test ear (IT.), is called masking (or clinical masking). The threshold obtained in the TF. is called the masked threshold, and implies that the masker was delivered to the NTT. Tn order to be able to deliver a masker into the Nik. a two-channel audiometer is needed so that the test sound Ebook Audiology science to practice (3E): Part 2 (tones or speech) can be routed to the Ik through one channel, and the masker can be routed to the Nik through the second channel. Most clinical audiEbook Audiology science to practice (3E): Part 2
ometers automatically route the masker to the Nik when masking IS selected.In Chapter 7. some basic principles of masking were presented so that you w9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2tric measures are expected to be true representations of the TE and not a reflection of hearing by the NTE. In Chapter 7. the principles of masking were presented as they pertained to thresholds for pure tones; however, as you will see in a later section of this chapter, when doing speech testing yo Ebook Audiology science to practice (3E): Part 2u must also be cognizant of the possible need for masking to prevent the speech signals from being heard in the NTE. This chapter provides details onEbook Audiology science to practice (3E): Part 2
when masking is needed and how to perform masking. The first part of the chapter will focus on masking for pure-tone thresholds and the second part of9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2the skull that potentially could be picked up by the Nik: When testing by bone conduction (BC) at any intensity level or when testing by air conduction (AC) at moderate and higher intensity levels, the sound vibrations can occur in the bones of the skull and. therefore, are able to be received by bo Ebook Audiology science to practice (3E): Part 2th cochleae through bone conduction. This becomes especially problematic when the NTT. has belter hearing than lhe TF. since the patient's response toEbook Audiology science to practice (3E): Part 2
the sound delivered to the TF could actually be a result of the patient hearing the sound through bone conduction in the NTT. When the signal deliver9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2always occurs by bone conduction (Studebaker, 1962; Zwislocki. 1953). Whenever cross-hearing could occur, masking of the NTT. will be needed. To prevent the patient from hearing the sound that may be heard through cross-hearing in the NTT. a masker (noise) is delivered to the NTF.. The patient is in Ebook Audiology science to practice (3E): Part 2structed to respond only to the pure tones or speech signals in the car being tested, and to ignore the noise that he or she will hear in the other eaEbook Audiology science to practice (3E): Part 2
r.INTERAURAL ATTENUATIONIt IS fairly easy to understand that when the bone vibrator is on the mastoid of one ear. the other cochlea is also being stim9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2uation of the sound in the NTE compared to the TE? Interaural attenuationEbook Audiology science to practice (3E): Part 2
ing the sound presented to the IE (i.e.. cross-hearing occurs), masking the NTE would be needed in order to establish the true thresholds in the IE.Ra9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2lare & Denenberg. 1987; Studebaker. 1967). For BC testing, the 1A is considered to be 0 dB. that is. the BC sound is the same level in both ears. For AC testing, the level of the pure tone presented to the IE that can cause vibrations of the skull are different for supra-aural earphones and insert e Ebook Audiology science to practice (3E): Part 2arphones; insen earphones have a higher 1A. The difference is primarily dependent on the relative surface area of the skull that is exposed to the souEbook Audiology science to practice (3E): Part 2
nd from the different AC transducers; supra-aural earphones have a larger area of exposure to the skull than9. MASKING FOR PURE TONE AND SPEECH AUDIOM9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2A varies somewhat across frequency, and will also vary across patients; however, for clinical purposes, minimum IA values are adopted instead of mean IA values to ensure that you do not miss masking someone with an IA below the average. The minimum IA for supra-aural earphones has been widely accept Ebook Audiology science to practice (3E): Part 2ed as 40 dB. This means that, when testing with supra-aural earphones, vibrations of the skull can occur at levels greater than or equal to (>) 40 dBEbook Audiology science to practice (3E): Part 2
HL. For insert earphones, a single minimum IA value has not yet been universally accepted or described in any standards. As you can see in Figure 9-1,9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2ary depending on depth of the earphone insertion; if not inserted deep enough, the IA may be less. Some audiologists choose to use a different minimum IA depending on the frequency when using insert earphones. However, the authors of this textbook have adopted a minimum LA for insert earphones of 55 Ebook Audiology science to practice (3E): Part 2 dB for all frequencies. This is a conservative, yet reasonable value, and simplifies the concept of masking with insert earphones by adopting one minEbook Audiology science to practice (3E): Part 2
imum IA value for all frequencies.1 The following are the minimum IA values adopted for this textbook for the different transducers;IA for bone vibrat9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2sary, but does not necessarily mean that the patient's actual IA is at the minimum level. In fact, most patients'This conservative minimum is based OU the lowest IA. which occurs at 2000 to 4000 Hz. For lower frequencies. the minimum 1A is at least 65 dB. Some audiologists may use IAs higher than th Ebook Audiology science to practice (3E): Part 2e 55 dB minimum IA adopted for this textbook.o TDH-49250500100020004000Frequency (Hz)FICURE9-I. Comparisonofinterauralattenuationval-ues for supra-aurEbook Audiology science to practice (3E): Part 2
al earphones and Insert earphones. Source: From Sklare and Denneberq, 1987, p. 298. Copyright 1987 by Lippincott Williams & Wilkins.will have an IA hi9Masking for Pure-Tone and Speech AudiometryAfter reading this chapter, you should be able to:1Understand why the non-test ear (NTE) needs to be maske Ebook Audiology science to practice (3E): Part 2d thresholds on an audiogram that the patient s IA IS higher than the minimum when you compare the unmasked AC threshold in the TE to the BC threshold in the NTE. For example, if a patient has an unmasked AC threshold in the TE of 65 dB HL and a BC threshold in the NTE of 5 dB HL. that patient s IA Ebook Audiology science to practice (3E): Part 2is at least 60 dB (and may even be more than 60 dB). However, you would still make the decision to use masking because 60 dB is greater than the minimEbook Audiology science to practice (3E): Part 2
um IA for either of the AC transducers.MASKERSGọi ngay
Chat zalo
Facebook