Comparison of the Minimum Plateau Width by Plateau and a New Method in People with Conductive Hearing Loss

BACKGROUND AND OBJECTIVES: In clinical masking, the plateau is a state in which the non-test ear (NTE) is completely masked by the noise and tone is heard only by the test ear (TE). At least 15 to 20 dB of plateau width is needed to obtain valid threshold. In the study, a part of plateau after initial masking level known as the minimum plateau width (mPW) was determined and compared by a new formula and the plateau searching method. SUBJECTS AND METHODS: Minimum plateau widths of air conduction were obtained in 29 participants with unilateral and 30 participants with bilateral conductive hearing loss (CHL) aged 20 to 45 years old by using step by step plateau method and mPW estimation by the formula between two points of masking diagram [mPW=(N2-N1)-(T2-T1)] and then the mPW of two methods was compared for each frequency. RESULTS: There was no significant difference between the minimum plateau width obtained by the plateau and formula methods for two given point of masking diagram in people with unilateral and bilateral CHL at octave frequencies from 500 Hz to 4,000 Hz. CONCLUSIONS: Threshold obtaining of TE by two tones for two noise levels delivered to the NTE is enough to estimate the mPW between these two noise points and it is not necessary that for clinicians to know the actual values of masking diagram components.

Satisfaction with Hearing Aids among Aged Patients with Different Degrees of Hearing Loss and Length of Daily Use

BACKGROUND AND OBJECTIVES: The evaluation of subjective benefits and positive effects of hearing aids in daily is important for measuring the treatment outcome. The aim of this project was to investigate the degree of satisfaction of aged users with their hearing aids using the Satisfaction with Amplification in Daily Life (SADL) scale, which emphasizes non-auditory factors contributing to satisfaction as well as benefit. SUBJECTS AND METHODS: The Persian version of SADL scale was completed by 40 patients who received monaural hearing aid fitting at south of the Iran from December 2013 and March 2014. SADL subscales of the SADL were evaluated according to the type and degree of hearing loss, the pure tone audiogram pattern and shape and type of the hearing aid. RESULTS: The results associated with the SADL subscales revealed a greater satisfaction associated with the Positive Effect and Service and Costs subscales. Subjects with different degree of hearing loss were very satisfied in terms of positive effect subscale. CONCLUSIONS: Participants reported a considerable level of satisfaction with their hearing aids. Appropriate guidance for using hearing aids and spending more time for counseling can improve the satisfaction level of this age group.

[ effect of acoustic reflex on contralateral suppression of transient-evoked otoacoustic emissions]

Contralateral suppression of transient evoked otoacoustic emissions [TEOAEs] test evaluates the efferent auditory system. In this test, acoustic reflex is an important confounding variable. In recent years, application of this test is growing especially in children suspect to central auditory processing disorder. Therefore, the magnitude of influence of this confounding variable on the suppression of TEOAEs should be made clear. The aim of this study was to investigate the impact of acoustic reflex on contralateral suppression of TEOAEs. This research was performed on 39 normal-hearing adults of both sexes and of 18-26 years of age. Tests were used for the determination of interaural attenuation [IA], acoustic reflex, TEOAEs and contralateral suppression of TEOAEs. TEOAEs amplitudes and their contralateral suppression were significantly higher in females and males respectively [p = 0.01]. The amount of TEOAEs suppression before reflex activity ranged between 2000 to 3000 Hz. Activation of acoustic reflex significantly increased the magnitude of suppression in all frequency bands [p