Vol 23 No 4 (2014)

Published: 2014-10-30

Research Article(s)

  • XML | views: 120 | pages: 1-9

    Background and Aim: Universal newborn hearing screening program (UNHS) using otoacoustic emission (OAE) has been expanded dramatically. The aim of this study was to compare the characteristics of OAE in different time periods.
    Methods: In this cohort study, 54 well babies were tested using screening transient-evoked otoacoustic emission in 12, 24, 36, 48 hours and 1 week of their age in Tamin Ejtemaii hospital of Zahedan, Iran. Parameters of "pass" and "fail" level, duration of the test, repetition rate for getting definite result and cooperation level of the parents were analyzed.
    Results: The failing rate decreased markedly with age. The major part of this decrement concerned to the age of 12 to 24 hours (left ear: p=0.012 and right ear: p=0.057). Only for the age of 12 hours, the test repetition reduced the failing rate significantly (left ear: p=0.001 and right ear: p<0.001). The test duration reduced significantly with age increment and decreased from the 75 second in age 12 hours to 21 second in age of 24 hours. The test time median for 36, 48 hours and one week of age was 13, 8.4 and 14.3 second, respectively. Among the 54 parents requested to come back for retest one week later, 5 (9.3%) cooperated.
    Conclusion: Age effect on referral rate were confirmed in this study; high referral rate and poor parent cooperation were the main problems in universal newborn hearing screening program in Zahedan city.

  • XML | views: 387 | pages: 10-20

    Background and Aim: Speech and language pathologists (SLP) often refer to phonological data as part of their assessment protocols in evaluating the communication skills of children. The aim of this study was to develop the Persian version of the phonological test in evaluating and diagnosing communication skills in Persian speaking children and to evaluate its validity and reliability.
    Methods: The Persian phonological test (PPT) was conducted on 387 monolingual Persian speaking boys and girls (3-6 years of age) who were selected from 12 nurseries in the northwest region of Tehran. Content validity ratio (CVR) and content validity index (CVI) were assessed by speechtherapists and linguists. Correlation between speech and language pathologists experts' opinions and Persian phonological test results in children with and without phonological disorders was evaluated to investigate the Persian phonological test validity. In addition, the Persian phonological test test-retest reliability was investigated.
    Results: Both content validity ratio and content validity index were found to be acceptable (CVR≥94.71 and CVI=97.35). The PPT validity was confirmed by finding a good correlation between speech and language pathologists experts' opinions and Persian phonological test results (r Kappa=0.73 and r Spearman=0.76). The percent of agreement between transcription and analyzing error patterns in test-retest (ranging from 86.27%-100%) and score-rescore (ranging from 94.28%-100%) showed that Persian phonological test had a very high reliability.
    Conclusion: The results of this study show that the Persian phonological test seems to be a suitable tool in evaluating phonological skills of Persian speaking children in clinical settings and research projects.

  • XML | views: 111 | pages: 21-30

    Background and Aim: Word definition is one of the complicated language skills that require education and linguistic awareness. In this study, comparison was made in word definition ability of children between ages of 4.5 to 7.5 years.
    Methods: This study was cross-sectional and descriptive-analytical in nature. Participants included 107 girls and boys who where in age group 1 (54-65 months), age group 2 (66-77 months), and age group 3 (78-90 months). They were selected by multistage sampling method and recruited from nurseries and primary schools in 1, 7, and 17 municipal districts of Tehran. Word definition task was performed on each subject. The reliability was assessed by two independent values and the validity was determined by the content. Kruskal-Wallis and Mann-Whitney U statistical methods were used for analysis.
    Results: Mean score of the content in word definition was significantly increased by age (p=0.001). In the second and third age groups there was no significant difference in the content of word definition. The most response that used in all ages was the functional response. With increasing age, error rate (p=0.002) and identical (p=0.003) responses significantly decreased; however, percentage use of combination II (p<0.001) responses significantly increased.
    Conclusion: By increasing age, quality of definitions in terms of content is improved and definitions change from functional and concrete responses to combination II definitions.

  • XML | views: 150 | pages: 31-39

    Background and Aim: Children with auditory processing disorders and impaired phonological working memory have difficulty in storing an accurate phonological representation of speech. Therefore, it is highly important to assess phonological working memory in this population. One of the methods in assessing phonological working memory is to use a non-sense syllable test. The aim of this study is to create a valid and reiable non-sense syllable test in order to evaluate phonological working memory in Persian speaking children with auditory processing disorders.
    Methods: In this cross sectional comparative study, 40 non-sense syllable words were developed according to the criteria of non-syllable word construction and under supervision of a linguistic specialist. The non-sense syllable test was assessed in 53 boys and 47 girls from 7 to 10 years of age. The content validity of the nonsense syllable words was assessed by experts. To evaluate the validity of the test, correlation between the results of the test and forward digit recall and backward digit recall tests were measured. The non-sense syllable test was performed twice to evaluate its relaibility.
    Results: The validity of the non-sense syllable test was 95.5 (SD=2). The correlation coefficient between nonsense syllable repetition, forward digit recall, and backward digit recall tests were 0.76 and 0.75 respectively (p<0.001). The correlation coefficient between different performances of non-sense syllable tests was 0.8 (p<0.001).
    Conclusion: These findings show that the non-sense syllable repetition test can be used to evaluate phonological working memory in Persian speaking children from 7-10 years of age.

  • XML | views: 180 | pages: 40-48

    Background and Aim: Diabetes mellitus is a metabolic disorder that affects multiple systems including the auditory and vestibular systems. Patients with diabetes mellitus complain of tinnitus and dizziness. The objective of this study is to assess the effects of diabetes mellitus types I and II on auditory and vestibular systems.
    Methods: We compared pure-tone audiometric results and cervical vestibular evoked myogenic potentials (cVEMPs) between 15 patients with diabetes mellitus type I (43.80 with SD 4.246), 15 patients with diabetes mellitus type II (48.13 with SD 2.973), and 10 normal volunteers (45.30 with SD 4.448). Age range of the participants was 40-50 years old.
    Results: Audiometric results showed normal hearing in both types of diabetes mellitus. In contrast, comparing amplitude of cVEMPs between diabetes mellitus and control groups showed statistically significant differences (p<0.05).
    Conclusion: In spite of normal audiometric results in patients with diabetes mellitus types I and II, there was abnormal vestibular responses involving vestibular end-organ and related central pathway.

  • XML | views: 147 | pages: 49-59

    Background and Aim: Cervical vestibular-evoked myogenic potential (cVEMP) is one of the diagnostic tests used in assessing vestibular function. Two aims of this study were to investigate implications of cervical vestibular evoked myogenic potential in children with spastic cerebral palsy (7-12 years), and to compare vestibular function in these children and normal children.
    Methods: In this cross-sectional study, myogenic potential was recorded in 31 children with spastic cerebral palsy (8 girls, 23 boys,7-12 years of age, with mean age of 8.77 years old and standard deviation of 1.52 years) and 31 normal children (13 girls, 18 boys with mean age of 8.77 years and standard deviation of 1.52 years). Cervical vestibular evoked myogenic potential was recorded with 500 Hz tone burst. The recorded parameters included p13 and n23 latency, p13-n23 pick to pick amplitude, and threshold.
    Results: Myogenic Potential was recorded in 31 normal children. They had bilateral responses. In children with cerebral palsy, 21 children showed bilateral responses, 3 children had only right-sided responses, 8 children had only left-sided responses, and two children did not show any responses. The statistical significant differences were shown between the two groups in n23, p13-n23 pick to pick amplitude, and threshold (p<0.05).
    Conclusion: These findings showed that cervical vestibular evoked myogenic potential can be used in children with cerebral palsy. There were significant differences in myogenic potential parameters between the two groups. More studies are needed to investigate the causes of these differences.

  • XML | views: 126 | pages: 60-68

    Background and Aim: Auditory lateralization is a binaural phenomenon that is the result of processing of interaural time and intensity cues in the central auditory system. The main advantage of this phenomenon in human is understanding speech in noisy environments due to the auditory sciene analysis and cocktail party effects. The aim of the present study was to assess the auditory lateralization ability in normal children.
    Methods: Participants were 80 normal school age children (8-11 years) of both genders, 42 girls and 38 boys. Lateralization functions were determined by interaural time difference (ITD) ranging from -880 to +880 µs and interaural intensity difference (IID) ranging from -10 to +10 dB for high-pass and low-pass noise.
    Results: Interaural intensity difference lateralization functions were linear, while the interaural time difference lateralization functions were S-shaped with a clear linear component from -220 to +220 µs and with an asymptote from -440 to -880 µs and +440 to +880 µs. Generally, interaural intensity difference errors were significantly less than interaural time difference tasks (p<0.0001). Age effect was only present in interaural time difference tasks (p=0.001).
    Conclusion: According to these results, children with the age of 11 years performed better in lateralization using interaural time difference cues compared to other children; whereas there was no difference in performance in all ages when using interaural intensity difference cues.

  • XML | views: 231 | pages: 69-76

    Background and Aim: CE-Chirp stimulus has been developed for stimulating more apical regions of the cochlea. Inadequacy of clinical information on the latency and amplitude characteristics of ABR evoked by CE-chirp at different levels in addition to discrepancy in identifying earlier ABR waveforms using CE-chirp stimulus are the reasons of this study.
    Methods: This study was done by recoding ABR to click and broad-band CE-chirp stimuli in the right ear of 15 non-randomly selected normal-hearing individuals with age range of 20-30 years old. Frequency of recordable waves I and III, as well as threshold, amplitude, and latency of wave V were compared in response to click and CE-Chirp at 20-80 dB nHL.
    Results: At 80 dB nHL, click stimulus evokes waves I and III more frequently than chirp stimulus (p=0.012 and p=0.016 respectively). At 20 and 40 dB nHL, wave V latency evoked by CE-Chirp is significantly longer than wave V latency evoked by click (p=0.012 and p=0.0001 respectively); however, at 80 dB nHL wave V latency evoked by CE-Chirp is shorter than click (p=0.0001). Wave V amplitude for CE-Chirp is significantly larger than for click at levels of 20, 40 and 60 dB nHL (p=0.0001, p=0.0001 and p=0.013 respectively). Wave V threshold is approximately 5 dB lower with CE-chirp compared to click (p=0.014).
    Conclusion: Except at high levels, CE-Chirp evokes wave V with larger amplitude and lower threshold than click. Possibility of recording earlier ABR waves is reduced with CE-chirp stimulus.

  • XML | views: 106 | pages: 77-83

    Background and Aim: Hearing loss affects human adjustment with environment and may be followed by mental complications such as behavioral problems. This study was conducted to investigate the effectiveness of group behavioral management training of mothers based on the model of positive parenting on the rate of behavioral disorders of primary school deaf students in Isfahan.
    Methods: The research method was semi-experimental with pre and post-test plan and control group. Using multi-stage sampling method, 30 mothers whose children demonstrated behavioral disorders symptoms were chosen and randomly assigned into two experimental and control groups. Data gathering was by parents’ form of child behavior checklist with confirmed validity and reliability. The obtained data was analyzed using covariance analysis method.
    Results: The results showed that there is significant difference between performance of experimental and control groups on the reduction of behavioral disorders symptoms in the post-test (p<0.001).
    Conclusion: It could be concluded that mother training based on the positive parenting model is effective on reducing behavioral disorders of their deaf child, and thus can be applied as an effective intervention method.

  • XML | views: 168 | pages: 84-92

    Background and Aim: The cochlea and vestibule are related developmentally. Therefore individuals with severe to profound sensourineural hearing loss have additional risk for vestibular dysfunction. The aim of this study was to assess saccular function using vestibular evoked myogenic potentials (VEMP) in children with severe to profound sensorineural hearing loss (SNHL) who are candidates for cochlear implant.
    Methods: Thirty children (17 males and 13 females) with bilateral severe to profound sensorineural hearing loss in the age range of 3-15 years participated in this study. 17 children (9 males and 8 females) with normal hearing in the age range of 3-13 years participated as the control group. All children in each group were evaluated for saccular function by performing vestibular-evoked myogenic potentials in both ears.
    Results: Comparison of mean threshold values between the two groups revealed statistically significant difference (p<0.05). In addition, comparison of mean amplitude values between the two groups revealed statistically significant difference (p<0.05). However, comparison of p13 and n23 latency values between the two groups revealed no significant difference (p>0.05). Out of the 30 children with bilateral severe to profound sensorineural hearing loss eight children (26.66%) had absent VEMP responses in both ears.
    Conclusion: Children with severe to profound sensorineural hearing loss who are candidates for cochlear implant had more potential for saccular abnormalities compared to normal-hearing children. Therefore, assessment of vestibular function is very important in this population.