Physical Options for Custom Hearing Aids

ABSTRACT

Selecting appropriate custom in-the-ear amplification is a process of integrating shell and circuitry characteristics that satisfy what the patient wants and needs with what is physically and electroacoustically possible. Options are influenced by many factors, including ear anatomy, type and degree of hearing loss, medical conditions, lifestyle and an individual's capabilities and communication needs. This article provides a practical overview of criteria used in the selection of hearing aid type, shell construction, special features or accessories, and discusses the acoustic advantages of custom hearing aids.

KEYWORDS

Amplification - selection criteria - acoustic advantages of custom hearing aids - directional microphones

REFERENCES

• 1 Microtronic A/S. DK Technical Data Sheet. Microphone Unit 6951.  Minnetonka, MN: Microtronic A/S 20019
• 2 Christensen L, Killion M. Lost on the way to the brain. Paper presented at the American Academy of Audiology Convention, Philadelphia, April 18-21, 2002
• 3 Cox R M, Alexander G C, Gray G. Personality and the subjective assessment of hearing aids.  J Am Acad Audiol . 1999;  1 1-13
• 4 Turner C, Cummings K. Speech audibility for listeners with high frequency hearing loss.  Am J Audiol . 1999;  1 47-56
• 5 Rankovic C. An application of the articulation index to hearing aid fitting.  J Speech Hear Res . 1991;  34 391-402
• 6 Ching T, Dillon H, Byrne D. Speech recognition of hearing-impaired listeners: predictions from audibility and the limited role of high frequency amplification.  J Acoust Soc Am . 1999;  2 1128-1140
• 7 Hogan C, Turner C. High-frequency audibility: benefits for hearing-impaired listeners.  J Acoust Soc Am . 1998;  1 423-441
• 8 Skinner M. Effects of frequency response, bandwidth and overall gain of linear amplification systems. In: Studebaker GA, Hochberg I, eds. Acoustical Factors Affecting Hearing Aid Performance, 2nd ed Boston, MA: Allyn & Bacon 1993: 133-165
• 9 Etymotic Research. QuickSIN Speech-in-Noise Test (Compact Disk).  Elk Grove Village, IL: Etymotic Research, Inc. 2001
• 10 Moore B. The use of psychophysical tuning curves to explore dead regions in the cochlea.  Ear Hear . 2001;  4 268-278
• 11 Moore B. Dead regions in the cochlea: diagnosis, perceptual consequences, and implications for the fitting of hearing aids.  Trends in Amplification . 2001;  1 1-34
• 12 Killion M, Clemis J. An engineering view of middle ear surgery.  J Acoust Soc Am . 1981;  69(suppl 1) S44A
• 13 Dillon H. Hearing Aids. New York: Thieme 2001
• 14 Creel L, Desporte E, Juneau R. Soft-solid instruments: a positive solution to the dynamic ear canal.  Hear Rev . 1999;  1 40-43
• 15 Kochkin S. MarkeTrak III: why 20 million people in the US don't use hearing aids for their hearing loss.  Hear J 1993;1:20-27; 2:26-31, 4:36-37 .
• 16 Staab W. Clarifying the CIC mystique.  Hear Rev . 1994;  7 19-20
• 17 Ricketts T, Mueller H. Making sense of directional microphone hearing aids.  Am J Audiol . 1999;  2 117-127
• 18 Christensen L, Bray V, Dreschler W, Ricketts T, Venema T. Directional Microphones and/or noise reduction. Paper presented at the American Academy of Audiology Convention, San Diego, CA, 2001
• 19 Fortune T, Preves D. Effects of CIC, ITC and ITE microphone placement on the amplification of wind noise.  Hear J . 1994;  9 23-27
• 20 Meskan M. Fitting completely-in-the-canal instruments.  Hear Rev . 1994;  8 25-28
• 21 Mueller H. CIC Hearing Aids: What is their impact on the occlusion effect?.  Hear J . 1994;  11 29-35
• 22 Shaw E. The acoustics of the external ear. In: Studebaker GA, Hochberg I, eds. Acoustical Factors Affecting Hearing Aid Performance Baltimore, MD: University Park Press 1980: 109-125
• 23 Gudmundsen G. Fitting CIC hearing aids: some practical pointers.  Hear J . 1994;  7 46-49
• 24 Bentler R. CICs: some practical considerations.  Hear J . 1994;  11 37-43
• 25 Killion M, Schulein R, Christensen L. et al . Real-world performance of an ITE directional microphone.  Hear J . 1998;  4 24-38
• 26 Killion M, Niquette P. What can the pure-tone audiogram tell us about a patient's SNR loss?.  Hear J . 2000;  3 46-53
• 27 Nilsson M, Soli S, Sullivan J. Development of the Hearing in Noise Test for the measurement of speech reception thresholds in quiet and noise.  J Acoust Soc Am . 1994;  2 2705-2715
• 28 Soede W, Berkhout A, Bilsen F. Development of a directional hearing instrument based on array technology.  J Acoust Soc Am . 1993;  94 785-798
• 29 Soede W, Bilsen F, Berkhout A. Assessment of a directional microphone array for hearing-impaired listeners.  J Acoust Soc Am . 1993;  94 799-808
• 30 Mueller H, Wesselkamp M. Ten commonly asked questions about directional microphone fittings.  Hear Rev . 1999;  1(suppl) 26-30
• 31 Ricketts T. Directivity Quantification in hearing aids: fitting and measurement effects.  Ear Hear . 2000;  1 45-58