Using the FONIX 7000 to Verify Coupler and Real-Ear Performance ...

More documents

Recommendations

Info

Table of Contents Introduction ............................................................................................................................3-4 Coupler Measurements ....................................................................................................... 4-26 1.1 ANSI S3.42-Broadband Signal ................................................................................... 10-12 1.2 ANSI S3.22-Puretone Signal ...................................................................................... 12-14 Telecoil Response (SPLITS) .................................................................................. 14-16 1.3 Group Delay and Phase ............................................................................................. 16-17 1.4 Input/Output ............................................................................................................... 18-19 1.5 Attack and Release .................................................................................................... 19-20 1.6 Noise Reduction ......................................................................................................... 21-25 1.6.1 Composite versus Digital Signal .................................................................... 21-22 1.6.2 Using Bias Tones .......................................................................................... 23-25 1.7 Wireless CROS .......................................................................................................... 25-26 Real Ear Measurements ..................................................................................................... 27-56 2.1 Real Ear Unaided Gain (REUG) ................................................................................. 29-32 2.2 Real Ear Insertion Gain (REIG) to Target ................................................................... 32-34 2.3 Front-to-Back Ratio .................................................................................................... 34-35 2.4 Real Ear Aided Response (REAR) in SPL .................................................................. 35-38 Real Ear Saturation Response (RESR) ...................................................................... 38 2.5 Live Speech Mapping ................................................................................................. 38-41 2.6 Noise Reduction with Bias Tones ............................................................................... 41-43 2.7 Occlusion Effect ......................................................................................................... 44-45 2.8 Loudness Discomfort Levels (LDL) ............................................................................. 45-47 Real-Ear-to-Dial Difference (REDD) ............................................................................ 46 2.9 Transcranial Thresholds (TCT) ................................................................................... 47-48 2.10 CROS and BICROS Verification ............................................................................... 49-51 2.11 Feedback ................................................................................................................. 51-54 2.12 Attenuation of a Hearing Protector Device ................................................................ 54-56 References .............................................................................................................................. 57
Coupler Measurements 3 Introduction In 2003, Angela Loavenbruck, then President of the American Academy of Audiology (AAA), asked the second author to consider chairing a Task Force whose goal was to develop a national guideline for fitting hearing aids to adults. Angela felt a new guideline was necessary because a) the AAA guideline for children was about to be published; b) as the national organization for audiologists, AAA needed to formulate its own guideline; and c) numerous advances have been made in technology since the ASHA guideline was published. Angela informed the second author that the current Task Force members included Harvey Abrams, Dennis Hampton, Todd Ricketts, and Robert Sweetow. Soon after assuming the chair, the second author asked Theresa Hnath-Chisolm, Darcy Benson, David Citron, and Helena Solodar to join the Task Force. Why a New Guideline? One might ask, "Why a new guideline?" There are several answers to this important question. First, as mentioned earlier, the last guideline was published by ASHA in1998. Since1998, there have been numerous advances in hearing aid technology as well as the methods used to verify and validate hearing aid fittings. Thus, the current standard needed to be updated to accommodate these advances. Second, there is increased interest in other professions in using evidence-based principles (EBP) when developing a new guideline. It was felt that in order for this guideline to have relevance, it too must use EBP to reinforce its recommendations. Third, AAA published a pediatric guideline (2004) and felt an adult guideline was also necessary. Fourth, there is considerable concern regarding the manner in which hearing aids are dispensed by audiologists. That is, current clinical practices implemented "in the field" may do little to differentiate how hearing aids are dispensed by audiologists and others and therefore would not be in line with AAA's goal for professional autonomy. How does this Guideline Differ from Previous Guidelines? The content and organization of this guideline differs significantly from the previously published ASHA guideline in several ways. First, it is the only guideline thus far to include a section specifically on auditory and non-auditory needs assessment. Second, it is the first to use EBP to support its recommendations. Within the guideline, EPB is also used to point out areas where the evidence may not be sufficient to support implementing some recommendations of the guideline. Finally, it is emphasized that a guideline is not static and needs to be re-evaluated every five years to assess the need for revisions as technology and the evidence changes. Relative to the issue of verification, there are some very specific recommendations within the guideline. For example, relative to quality control (pages 23-24) there is the statement: “Electroacoustic verification of all hearing aids (new and repaired) is recommended. This verification should be completed prior to fitting to ensure the hearing aid is in working order and to provide a benchmark for future quality control measures.” Also, there is a call for “Verification of features…prior to the hearing aid fitting.” Features can include directional microphones, feedback management, expansion, noise reduction, or control of the occlusion effect. In pages 25-30, there are these additional statements:
Page 1: Using the FONIX 7000 to Verify Coup
Page 5 and 6: Coupler Measurements 5 the CIC coup
Page 7 and 8: Coupler Measurements 7 Plug the ven
Page 9 and 10: Coupler Measurements 9 Figure 8 - I
Page 11 and 12: Coupler Measurements 11 2. Level th
Page 13 and 14: Coupler Measurements 13 Figure 13 -
Page 17 and 18: Coupler Measurements 17 STEP-BY-STE
Page 21 and 22: Change “Display” to Gain Couple
Page 23 and 24: Coupler Measurements 23 1.6.2 Verif
Page 25 and 26: Coupler Measurements 25 Note… The
Page 27 and 28: Real Ear Measurements 27 REAL EAR M
Page 29 and 30: Real Ear Measurements 29 2.1 Measur
Page 31 and 32: Real Ear Measurements 31 10. Config
Page 33 and 34: Real Ear Measurements 33 STEP-BY-ST
Page 35 and 36: Real Ear Measurements 35 9. Use [F2
Page 37 and 38: Real Ear Measurements 37 5. If a pa
Page 39 and 40: Real Ear Measurements 39 Figure 50
Page 41 and 42: Real Ear Measurements 41 16. Use [F
Page 43 and 44: Real Ear Measurements 43 6. Press [
Page 45 and 46: Real Ear Measurements 45 8. Insert
Page 47 and 48: Real Ear Measurements 47 17. When t
Page 49 and 50: Real Ear Measurements 49 2.10 Inser
Page 51 and 52: Real Ear Measurements 51 Measuring
Page 53 and 54:
Real Ear Measurements 53 Figure 69
Page 55 and 56:
Real Ear Measurements 55 5. Use [F1
Page 57:
References American National Standa
show all

Using the FONIX 7000 to Verify Coupler and Real-Ear Performance ...

Create successful ePaper yourself

Delete template?

Save as template?