난청 정도에 따른 보청기의 이어팁의 음향학적 효과 = The Acoustic Effects of Hearing Aid Eartips According to Degree of Hearing Loss

다국어 초록 (Multilingual Abstract)

The Receiver-in-canal(RIC) hearing aids have been widely used to restore hearing for people with hearing loss. The eartips can affect the gains of hearing aids and the outcomes of hearing aid fitting because they acoustically couple between the RIC hearing aid and the ear canal. Therefore, this study investigated how the different types of eartips affect the functional gains and the fitting outcomes of hearing aid according to the degrees of hearing aids.
Twelve adults consisted of six individuals with moderate hearing loss and six individuals with moderately severe hearing loss participated in this study. Functional gain was measured in a sound-field environment using four eartip types (open, tulip, sleeve vent, and double eartips). Manufacturer fitting gain and comfortable fitting gain were obtained for each eartip condition. Frequency-specific functional gain data were analyzed using two-way mixed analyses of variance (ANOVA), with eartip type as the within-subject factor and degree of hearing loss as the between-subject factor. Paired-sample t-tests were conducted within each eartip condition to compare manufacturer-recommended and preferred fitting gains.
The results showed that functional gains were significantly different across eartip types at all tested frequencies. The functional gains were generally greater in the low and mid-frequency regions and gradually decreased as frequency increased, with a more pronounced reduction observed above 4 kHz. Eartips with higher occlusion, particularly the double eartip, consistently yielded greater functional gain than open eartips, while tulip and sleeve vent eartips demonstrated intermediate effects. Significant interaction effects between eartip type and degree of hearing loss were observed at specific frequencies, indicating that the acoustic benefit of eartip selection varied according to hearing loss degrees. In addition, comparisons between manufacturer fitting gain and comfortable fitting gain revealed significant discrepancies for more occlusive eartips, regardless of hearing loss degree.
These findings suggest that eartip selection in RIC hearing aids should be considered a critical fitting variable rather than a secondary adjustment. The acoustic effects of eartips vary across frequency regions and differ according to the degree of hearing loss, indicating the importance of incorporating frequency-specific eartips and hearing loss severity-dependent considerations into clinical hearing aid fitting and gain.

목차 (Table of Contents)

• Ⅰ. 서 론 1
• 1. 연구의 배경 및 목적 1
• 2. 연구 문제 5
• Ⅱ. 이 론 적 배 경 6
• 1. 난청의 정의 및 분류 6
• 가. 난청의 정의 및 유형 6
• 나. 난청의 중증도 7
• 다. 난청 중증도에 따른 청각적 특성 변화 8
• 2. 보청기의 필요성 및 종류 11
• 가. 보청기의 정의 및 필요성 11
• 나. 보청기 종류 12
• 3. 보청기 적합 14
• 가. 보청기 피팅 시 고려 요소와 기능이득 14
• 나. 보청기 적합 프로그램과 실이측정 비교 17
• 4. 이어팁(eartip)의 구조와 음향학적 특성 20
• 가. 이어팁 구조와 음향 특성 20
• 나. 이어팁 구조에 따른 폐쇄 효과 21
• 5. 난청 중증도에 따른 이어팁 적용 효과 23
• Ⅲ. 연 구 방 법 25
• 1. 연구 대상 25
• 2. 연구 방법 및 절차 28
• 3. 자료 분석 및 통계 처리 30
• Ⅳ. 연 구 결 과 31
• 1. 주파수별 기능이득 비교 31
• 가. 0.25 kHz 34
• 나. 0.5 kHz 34
• 다. 1 kHz 35
• 라. 2 kHz 36
• 마. 4 kHz 37
• 바. 8 kHz 38
• 2. 이어팁별 기능이득 분석 39
• 3. 제조사 권장 피팅값과 편안한 수준의 피팅값 비교 42
• 가. 중도 난청군 42
• 나. 중고도 난청군 47
• 4. 주파수별 기능이득 및 피팅값 비교 52
• Ⅴ. 논 의 및 결 론 60
• 1. 이어팁 종류에 따른 기능이득의 주파수별 특성 60
• 2. 제조사 권장 피팅값과 편안한 수준의 피팅값과 기능이득의 관계 61
• 3. 이어팁 종류와 난청 중증도 상호작용의 임상적 의미 63
• 4. 연구의 제한점 및 향후 연구 필요성 64
• 참고문헌 68