Vol 30 No 1 (2021)

Review Article(s)

  • XML | PDF | downloads: 428 | views: 376 | pages: 1-8

    Background and Aim: Approximately 20% of general population is struggling with tinnitus. Recent theories on tinnitus are mainly based on impairments in the central auditory system that can lead to tinnitus. Recent studies have shown that tinnitus is not simply a result of the involvement of one brain region or pathway; but it can be caused by simultaneous involvement of multiple brain regions. Due to lack of information about the tinnitus etiology, site, and pathophysiology, there is still no any specific and common method for its management. In recent years, neuromodulation techniques such as transcranial direct current stimulation (tDCS) has been proposed for management of tinnitus. In this study, we aimed to review the role of tDCS in tinnitus management.
    Recent Findings: Based on the inclusion criteria, 7 eligible articles were selected for review. Most of them showed the beneficial effects of tDCS on tinnitus management.
    Conclusion: The tDCS can be an effective technique for management of tinnitus. One of the main challenges for using tDCS in tinnitus patients is the differnce in stimulation parameters; therefore, more studies are recommended for obtaining its ideal parameters.

  • XML | PDF | downloads: 232 | views: 204 | pages: 9-17

    Background and Aim: In a bimodal fitting, one ear is stimulated acoustically with a hearing aid and the other is stimulated electrically with a cochlear implant. This paper provides a brief summary of the concept of bimodal fitting, binaural hearing and its importance, the hearing benefits of binaural hearing in bimodal fitting, candidacy and hearing aid adjustment in bimodal fitting cases.
    Recent Findings: Researches have shown that bimodal fitting offers a wide range of hearing benefits over unilateral cochlear implants, such as better speech perception in noise, better musical perception, and a better understanding of pitch and tone perception and naturalness of sound perception.
    Considering the binaural hearing advantages in bimodal fitting users, it can be concluded that users of unilateral cochlear implants who have measurable residual hearing in their non-implanted ear can use a hearing aid in that ear and enjoy binaural hearing advantages. The hearing aid should be fitted in a way to complement the information obtained through cochlear implantation.

Research Article(s)

  • XML | PDF | downloads: 197 | views: 419 | pages: 18-23

    Background and Aim: The subjective visual vertical (SVV) is commonly considered as an indicator of the sense of orientation and attributed to the utricular function. The present study examined the impact of different head tilt angles on SVV among the normal individuals.
    Methods: SVV was measured in 47 normal participants (30 males and 17 females; mean ± SD age: 22.14 ± 3.46) using a virtual goggle and forced-choice paradigm and was applied twice in 0º, 15º, 30° and 45º to the left or to the right. In addition, difference in mean of SVV in zero and non-zero positions was compared.
    Results: There was a statistically significant difference between the mean SVV results of 0º and 15º (p ˂ 0.001). The comparison of mean SVV results between 0º and 30º, and between 0º and 45º were not significant (p > 0.05). In addition, comparison of SVV results between rightward and leftward tilt of 15º was statistically significant (p ˂ 0.001). The latter comparison was not significant for 30º and 45º (p > 0.05).
    Conclusion: Our results showed that head tilt angle of 15º have a substantial impact on the virtual SVV. These findings must be taken into account in the growing body of research that uses the SVV paradigm in clinical populations.

  • XML | PDF | downloads: 162 | views: 371 | pages: 24-32

    Background and Aim: The threshold of octave masking test has been used to assess the growth rate of aural harmonics, the intercept point helped differentiate between normal-hearing individuals and sensorineural hearing loss due to noise exposure. With fewer literatures that have been documented, there is a need to explore this test procedure, and hence the purpose of this research is to evaluate the utility of the threshold of octave masking (TOM) procedure in understanding the frequency selectivity and non-linear function of cochlea.
    Methods: A total of 10 adults (20 ears) were con­sidered for the test. The TOM test procedure was performed on the subjects where the subjects had to identify the presence of a maskee tone (1 kHz) in the presence of a masker tone (500 Hz) across 5 dB increment of masker tone until the subjects uncomfortable level. A line graph was drawn, extrapolated to identify the point of intercept, which is the threshold of octave masking.
    Results: Results reveal that 17 ears did not have a linear growth but had a 10 to 20 dB gap after a particular maskee level. The intercept point of the initial two extreme points was relatively more than the intercept point of the extreme points at higher intensities.
    Conclusion: Results from the present study have thrown light on the fact that TOM can be used as a test to measure the frequency selectivity along with the tests of psychophysical tuning curves, notched noise method, non-simultaneous masking, and other non-peripheral masking phenomena.

  • XML | PDF | downloads: 235 | views: 290 | pages: 33-41

    Background and Aim: Presbycusis is a prevalent chronic condition in the elderly which may have potential adverse effects on social and emotional aspects of their life. There is no one to one relationship between audiogram and the perceived handicap in elderly. A good way to measure hearing handicap are self-assessment tools. This study was aimed to translate, adapt and establish face validity of Short form of Hearing Handicap Inventory for the Elderly (HHIE-S) and the correlation with pure-tone and speech audiometry results as well as score of the other self-assessmnet tool (Self-Assessment of Communication: SAC) in the Iranian elderly.
    Methods: HHIE-S was translated into Persian and face validity was established.  It was administered in 80 elderly participants. Correlation of their scores with their pure tone averages of 3 and 4 frequencies (PTA0.5-1-2 and PTA0.5-1-2-4), word recognition score (WRS) in quiet, and SAC sco­res was determined.
    Results: The experts mean scores to PHHIE-S was 99.63%. There were significant correlations between PHHIE-S with SAC (r = 0.89; p < 0.001), PTA0.5-1-2 (r = 0.4; p < 0.001), PTA0.5-1-2-4 (r = 0.6; p <0.001) and WRS (r = -0.4; p < 0.001). There was no significant gender effect on any of the measures (p > 0.05).
    Conclusion: Simply evaluation of the hearing levels is not adequate in elderly. Self-assessment tools can shed light on the specific disability induced by hearing loss. PHHIE-S appears to be an easy and fast tool that may helpful to distin­guish patients who might need rehabilitative services.

  • XML | PDF | downloads: 147 | views: 331 | pages: 42-49

    Background and Aim: One of the consequences of aging is temporal processing impairment and reduced neural synchronization, which reduces speech comprehension in challenging situations such as noisy and reflective environments. This study aimed to develop a novel temporal processing-based auditory training program for the senior users of hearing aids.
    Methods: The program was designed based on different aspects of temporal processing and consists of multiple duty including: 1) detect the number of stimuli, 2) detect the pitch of the stimuli, 3) detect the duration pattern, 4) detect the number of nonsense speech stimuli in noise, and 5) detect the gap in noise. The program consists of 36 sessions (1800 exercises) and one or more features of temporal processing are challenged in all sections.
    Results: Content validity ratio, content validity index and impact score were used for validation. The results showed acceptable validity.
    Conclusion: Since training exercises can improve the physiological representation of sounds by changing hearing maps and temporal decoding, and these changes lead to improved perception, therefore, the auditory rehabilitation program for the seniors with emphasis on the temporal features of speech, was designed and developed. So it is hoped that with the implementation of the rehabilitation program in the seniors with hearing loss, the effects of age related hearing loss, including depression and social isolation, will be reduced to some extent.

  • XML | PDF | downloads: 207 | views: 382 | pages: 50-55

    Background and Aim: Evaluation of word recognition score requires multiple lists that must be similar in terms of difficulty level. There is currently no such word lists for the Persian language. The aim of this study was to construct several lists of Persian monosyllabic words with psychometric homogeneity.
    Methods: The most common monosyllabic words were collected from a book of Persian word frequency. The selected monosyllabic Consonant-Vowel-Consonant (CVC) words were presented randomly to 30 normal hearing participants with the age range of 18 to 25 years. The presentation level was from 0 to 40 dB in 8 dB increments. The characteristics of psychometric function were determined for all words using the logistic regression.
    Results: The Persian CVC monosyllabic words have different difficulty levels with threshold varying from 2.8 to 37.2 dB HL and the slope from 2.3 to 16.4 %/dB.
    Conclusion: The final result of the present study is three full lists of monosyllabic words with CVC syllabic structure that have the same mean threshold and slope of psychometric function. The 25-word half-lists of each full list are similar in terms of psychometric characteristics.

Case Report(s)

  • XML | PDF | downloads: 162 | views: 257 | pages: 56-61

    Background: Osteopetrosis (OP) is a rare disease of the skeletal system that can be associated with complications such as bone fracture, nerve dysfunction and deafness due to increased bone density and reduced bone quality. In this regard and due to the challenge that it can cause for cochlear implantation (CI), in this study we aimed to report CI conducted on two patients with OP in Iran.
    The Case: Patients were two women diagnosed with OP and bilateral sensorineural hearing loss (SNHL) who underwent CI in the right ear. Preoperative PTA showed a hearing threshold decrease of more than 100 dB in both patients. A standard cochleostomy was performed in one patient and endoscopic surgery in the other pati­ent through the external ear canal. One month after surgery, the hearing threshold improved by 60−90 dB in both patients. No facial nerve palsy or implant extrusion/migration was observed after surgery.
    Conclusion: Although technically challenging, CI seems to be a safe and effective method to improve the SNHL in patients with OP. The path for electrode insertion should be tailored to meet the conditions and anatomy of patients.