Normalization of Bone Conduction Auditory Brainstem Evoked Responses in Normal Hearing Individuals.

OBJECTIVES: Auditory brainstem responses (ABR) are used to evaluate the peripheral and central functions of the auditory tract. Air and bone-conduction auditory stimuli are used to evaluate the type and degree of hearing loss. The wave latencies and interpeak latencies (IPLs) are the important diagnostic data in ABR tests. Gender and age of the patients are some of the factors affecting these latencies. This study investigated the effects of age and gender on the wave and IPLs of bone-conduction ABR. MATERIALS AND METHODS: One hundred healthy individuals (50 women and 50 men) aged between 10 and 60 years were enrolled into this study, and both ears of all subjects (200 ears total) were included in the assessments. Based on their age, the subjects were equally divided into five groups, and each group consisted of 10 men and 10 women. RESULTS: The findings showed a significant difference in wave latencies and IPLs between the two genders (p<0.05). Depending on stimulus intensity, wave latencies also showed statistically significant differences between the age groups (p<0.05). However, no significant difference was noted between the age groups regarding IPLs. CONCLUSION: Normative values that covered wave latencies and IPLs evoked at stimulus intensities of 50, 30, and 10 dB nHL were established for the clinical use and use as a reference for the bone-conduction ABR testing procedure.

Evaluation of the Relationship Between the Air-Bone Gap and Prolonged ABR Latencies in Mixed-Type Hearing Loss.

OBJECTIVE: The aim of this study was to determine the air-bone gaps in adults with mixed-type hearing loss using air-conduction auditory brainstem response (ABR) latencies. MATERIALS AND METHODS: Thirty adults with mixed-type hearing loss (study group) and 30 adults with normal hearing (control group) were included in this study. Before performing ABR measurements, ear, nose, and throat examinations, pure tone audiometry, speech audiometry, acoustic immittance audiometry, and transient evoked autoacoustic emission testing were performed for all participants. Absolute latencies of I, III, and V waves and interpeak latencies (IPL) at 90 decibel hearing level dB nHL were evaluated and compared with air-bone gap results. RESULTS: ABR latencies using click and tone-burst stimulation were obtained and found to be longer in the mixed-type hearing loss group than in the normal hearing group (p<0.05). A moderate positive relationship was detected between the air-bone gap and wave III/V latencies at 0.5/1 kHz, I-V/I-III/III-V IPL at 1 kHz. Only one strong relationship was found between 1 kHz air-bone gap and I-V IPL. CONCLUSION: In this study, the magnitude of the air-bone gap could not determined using prolonged ABR latencies. Delays in ABR latencies were observed, but prolonged ABR latencies was not helpful for calculating the air-bone gap on mixed-type hearing loss.

Evaluation of Hearing Function by Auditory Brainstem Response in Newborn Patients with Hydrocephalus before and after Ventriculoperitoneal Shunt Surgery.

BACKGROUND/AIM: There is currently no objective evaluation of hearing in patients with hydrocephalus (HCP), and we could not find any study in the literature comprising a sufficient number of patients with a high level of scientific evidence. In the current study, we used the auditory brainstem response (ABR) test to assess whether hearing function in patients with HCP is altered after ventriculoperitoneal shunt surgery. METHODS: In total, 20 newborn patients with HCP (13 female, 7 male) were enrolled in this study. For each patient, ABR testing was performed at three time points: 1 day prior to the operation and on days 7 and 90 after the operation. ABRs using click stimuli of 90, 70, 50 and 30 dB nHL (normal hearing level) were achieved for V-wave latency, and I-III and I-IV interpeak latencies for both ears were recorded. Variance analysis for parametric data and Tukey's post hoc honest significant difference test were used to demonstrate the relationship between the results obtained from the different recording periods. Results were considered significant at p < 0.05, and 95% confidence intervals were calculated. RESULTS: The mean values of the ABR tests were compared between the pre- and postoperative results, which showed an increase (faster transmission) of nerve conduction velocity of 0.2 ms. The results were not statistically significant for 50 and 90 dB (p > 0.05) but were significant for 30 and 70 dB (p < 0.05). CONCLUSION: Diagnosis in hydrocephalic patients is important not only for the treatment but also for the prevention of HCP-associated complications. Early treatment appears to be promising in terms of auditory benefit. Prompt diagnosis and treatment are therefore essential as soon as possible.

[Examination of relationship between level of hearing and written language skills in 10-14-year-old hearing impaired children]. / Isitme engelli 10-14 yas arasi çocuklarda isitme düzeyi ile yazili dil becerileri arasindaki iliskinin incelenmesi.

OBJECTIVES: This study aims to review the relationship between written language skills and factors which are thought to affect this skill such as mean hearing loss, duration of auditory deprivation, speech discrimination score, and pre-school education attendance and socioeconomic status of hearing impaired children who attend 4th-7th grades in primary school in inclusive environment. PATIENTS AND METHODS: The study included 25 hearing impaired children (14 males, 11 females; mean age 11.4±1.4 years; range 10 to 14 years) (study group) and 20 children (9 males, 11 females; mean age 11.5±1.3 years; range 10 to 14 years) (control group) with normal hearing in the same age group and studying in the same class. Study group was separated into two subgroups as group 1a and group 1b since some of the children with hearing disability used hearing aid while some used cochlear implant. Intragroup comparisons and relational screening were performed for those who use hearing aids and cochlear implants. Intergroup comparisons were performed to evaluate the effect of the parameters on written language skills. RESULTS: Written expression skill level of children with hearing disability was significantly lower than their normal hearing peers (p=0.001). A significant relationship was detected between written language skills and mean hearing loss (p=0.048), duration of auditory deprivation (p=0.021), speech discrimination score (p=0.014), and preschool attendance (p=0.005), when it comes to socioeconomic status we were not able to find any significant relationship (p=0.636). CONCLUSION: It can be said that hearing loss affects written language skills negatively and hearing impaired individuals develop low-level written language skills compared to their normal hearing peers.