The cut off points of 90th percentile of acoustic reflex thresholds were determined in the normal and sensory hearing loss.All subjects had measurable hearing(ANSI-1969≤110 dBHL) in three frequencies of 500,1000 and 2000Hz.

While hearing loss was more than 55dB, The cut off point was higher in studies that NR responses was included.

In cases that hearing loss was less than 75dB, 90th percentile can be used in diganosis of retrochochlear lesions.Since Acoustic reflexes are absent in both mentioned pathologies in greater amount of hearing loss,It would be less efficient in diffrential diganisis of cochlear and retrochochlear lesions to use acoustic reflex thresholds under the mentioned circumstances.

Hearing function can affect communication skills and especially speech and language abilities.As a result, most of the attempts in behavioral audiometry have focused on the improvement and rectification of the techniques for hearing evaluations of the infants and children.Crib-O-gram and the methods suggested by northern & Downs are some of the mentined protocoles.

For years a significant advance for evaluating hearing sensitivity of children have been taken place. say, behavoral visual audiometry, VRA, TROCA and play audiometry. some studies also have been performed regarding to the use of BOA technique in mental retarded children and its success in evaluating hearing sensitivity in such children.other protocoles use rewarding thechniques for reinforcing child's responses which have been demonstrated to be success in the evaluation.

In addition,by comparying the results of frequency and intensity discrimination (by means of Luescher test), the changes in the resonance frequency of the outer ear and loudness conmfortable level(LDL), one can study the process of hearing development in children.

It has always been attempted that systems connected to the ear through hearing aids efficiently meet the patient expectations. It is recommended to avoid using occluded earmolds when the hearing is normal or there is mild hearing loss. In order that natural sound  reaches to the ear, the ear canal should stay open as much as possible.To achieve the above goal and the suitable acoustic modifications, non-occluding ear molds are beneficial.

Hearing aid selection as the first step in modifying the hearing loss is a critical point . people with severe to profound hearing loss need special consideration. In order to determine the amount of gain and output of hearing aids, some formulae are presented. Although most of these formulae are planned for mild to moderate hearing loss, they are used for severe to profound hearing losses. POGO method is one of these formulae.This method, based on halving the hearing threshold, is not suitable for profound hearing loss. There are some considerations in revising this method for severe to profound hearing loss and it’s name has changed to POGO II, too.

Hearing function can affect communication skills and especially speech and language abilities.As a result, most of the attempts in behavioral audiometry have focused on the improvement and rectification of the techniques for hearing evaluations of the infants and children.Crib-O-gram and the methods suggested by northern & Downs are some of the mentioned protocols.For years a significant advance for evaluating hearing sensitivity of children have been taken place. say, behavioral visual audiometry, VRA, TROCA and play audiometry. some studies also have been performed regarding to the use of BOA technique in mental retarded children and its success in evaluating hearing sensitivity in such children.other protocols use rewarding techniques for reinforcing child's responses which have been demonstrated to be success in the evaluation.In addition,by comparing the results of frequency and intensity discrimination (by means of Luescher test), the changes in the resonance frequency of the outer ear and loudness comfortable level(LDL), one can study the process of hearing development in children.

 This is a study performed following the study between the years 1980 to 1982 to investigate risk factors and diagnostic and rehabilitative patterns in a group of newborns suffered hearing loss in a city centre. The current findings which have been attained from 1983 to 1988 manifested that just one third of the deaf newborns can be tracked by means of common auditory evaluation tests in the Neonatal Intense Care Unit (NICU). Although these newborns have been followed sooner than the infants in the Well Baby Nursery (WBN). The age for enrolling in the Parent-Infant Program for both groups is approximately 20 month. During these 8 years it has been detected that the common age for taking part in the rehabilitative programs for newborns is 1 year or more greater than that recommended by Joint Committee on infant hearing

Sudden hearing loss is a type of hearing loss that occurs in three successive frequencies by more than 30 dB and in less than 72 hours. Every 10 person in 100000 in the world and 25000 people in USA suffer this kind of hearing loss. The average age of the onset is 43 years old.

It is difficult for clinicians to make parents aware of any disease or permanent handicap of their children.It is crucial to have vivid picture of the reactions to such crisis in order to manage severe psychological effects of the mentioned situations such as depression and unhappiness. Confronting the situation parents have diverse feelings regarding the pregnancy period, birth time and handicap diagnosis and these are the factors that shape the parent’s upcoming reactions. Common feedbacks to the crisis are refusing the problem, keeping their child away from society, the emotions that provoke disappointment, asking about the reasons for hearing loss, referring to religion, condemning the physician, feeling sin and changing doctor frequently. When parent accept the situation and that hearing could not recurrent and understanding the natural reasons back on their child’s handicap, they can manage the situation constructively.

Many people around the world are in need for using hearing aid, a prothesis which is prescribed for compensating the hearing loss in hard of hearing patients.Although Hearing aid has crucial role in improving hearing skills in such patients, it has many psychological effects and Social premonitions for the users.we will discuss some of these distresses and the common approaches for resolving economical, cosmetic and the emotional and social problems relted to hearing aid will be discussed.

Various risk factors in industrial environments can affect hearing status and healthy in today’s modern society. Noise control and hearing conservation program is very crucial in preventing workers exposed to high levels of noise in the work places.In the current article we are going to discuss issues such as industrial noise control, noise characteristics and standards and techniques for noise control. Then the methods for individual hearing conservation and medical care will be described in details.

Estimation of the age of hearing loss diagnosis in every society is recommended to be compared with standard criteria to establish common dirth in management and rehabilitation. This study was conducted in order to determine the age of hearing loss diagnosis with respect to common criteria in Baghche-Ban school of hard of hearing children in Tehran.Methods:  In this retrospective cross-sectional study, 445 children in stages 2, 6 and 10 of Baghche-Ban school of hard of hearing participated. the research was performed by means of the three-stages questionaires that children filled with help of their parents.Results: The mean age of detection of hearing loss  in both acquired and congenital hearing loss in children was 3.5 year-old. while the age in which hearing loss was doubted was 1.8 year-old. In another word the mean age of hearing loss detection decreased as the hearing loss increases(in moderate- profound hearing loss)(P<0.01).Conclusion: among the refrence sources for refering children with hearing loss the least refering was related to physicians. Adversly the mean age of doubting and detection of hearing loss increased in children with family history of hearing loss.(P<0.01). Meanwhile no relationship was detected between the age of diagnosis of hearing loss and the number of deaf members in the family(P<0.02).

In this article we aimed at studying the function of Melanin in the inner ear. To reach this goal TTS was studied in people with blue or brown eye color. Subjects were 68 male teenagers with normal hearing. Auditory thresholds were obtained by means of high frequency audiometry (.8-8KHz)before and after TTS.  We used narrowband noise with frequency width of 1665-2335Hz, central frequency of 2 KHz, intensity of 105dBSPL and duration of 10 minutes. A significant difference was discovered in the average TTS of this two group in the frequency range of 2-8 KHz. Brown-colored eye boys manifested the least TTS and the blue- colored eyes one the most discovered TTS.

Recent studies have demonstrated that outer hair cells play two functional roles in the ear: one is the sensory function and the other is motor one. The function of OHCs in being trigered with very poor signals can not be overlooked. This mechanism would lead in improving the sensitivity of the ear. As stimulus intensity increases, little by little, OHC will reach its saturation level and finally the amplification effect decreases.Otoacoustic emissions could be reverberations produced by the responses of outer hair cells .Any decrease in the number of OHCs can cause a mechanical split in the fine tuning mechanism of the organ of corti and result in hearing loss.

A concise Description of Non-linguistic features (Such as Familial, educational and Health information) and linguistic skills in hard of hearing children will be helpful in compensating for their disabilities. In the current study we studied 75 school-Children with average hearing Thresholds of 55-70dB in better ear. All the subjects aged between 8-16years-old with the average age of 11.04.We studied 27 non-linguistic variables by using questionnaire and 32 grammatical variables by studying evoked speech in the participants. The average utterance length of the subjects was estimated 2.763 words. 29% of the all participants' utterances was accurate and just 16.3% of the verbs were produced accurately.One of the most common errors in sentence and verb level, was the mistaken ably omitting of the structural features, the tense problem of the verb and also the mismatching between subject and verb. We also observed a significant correlation between some non-linguistic features such as grade, previous education in conventional schools and the rate of hearing aid usage and the number of accurate utterances in participants.

Background: hearing loss is a major health care problem that tends to retard the developmental milestones of children. It takes early detection and intervention to avoid a permanent loss in acquisition of speech and cognitive functions. Hence, the importance of hearing screening in all children especially in the developing world for accurate statistics and early intervention is clear. This work was aimed at predicting hearing in children by means of acoustic reflex measurements
Method: In this study which was performed in 1995, 146 ears(86 children aged between 5-10years old referring to audio logy clinic in Tehran university of medical sciences between august 1995 and February 1996) were evaluated (amongst 95 were normal and 51 ears with SNHL<84dB).the methods Niemeyer and Destrehan formula ,Lilly2 equation, un weighed Sensitivity prediction by acoustic reflex, weighed sensitivity prediction by acoustic reflex to establish their clinical viability.
Results: findings demonstrated that weighed sensitivity prediction by acoustic reflex(WASPAR) have a good correlation with conventional audiometric evaluation(K=.78) and also it has good sensitivity, Specificity , Negative predicted value(NPA) and positive predicted value (PPV).
Conclusion: In case that conventional audiometry is not applicable, WASPAR is a good objective choice in lieu of subjective tests.

The incidence of severe hearing loss after coronary artery bypass graft surgery has been as rare as 1/1000 surgery (Plasse et al., 1981). To evaluate possible changes in the auditory status, audiograms were taken before and after this operation. Our objectives were to: 1) evaluate hearing losses that were not necessarily severe and 2) examine the factors associated with any auditory insult. we selected patients among a group without any history of hearing problems and the intake of any ototoxic drugs. All patients underwent careful examination and hearing evaluation the day prior to surgery. 6 days after surgery they were examined again and asked about any hearing problems or experience of tinnitus. Various operative details were taken and the post-operative drug record examined. Patients who were too ill for retesting, or who had been given sedative or ototoxic drugs or opiate analgesia, were dropped from the study. The whole procedure was repeated on a control group of 20 patients who were having thorocotomy but without being placed on a cardiopulmonary bypass. From the bypass sample of 40 ears, five of them (four individuals) had an individually statistically significant high-frequency hearing loss. The results showed a statistically significant difference between the bypass group and the control group, with the bypass patients having worse threshold shifts following the operation.Discriminant analyses have shown that those patients suffering hearing impairment may be discriminated principally with four variables: the patient's age, minimum temperature and minimum blood pressure during the operation, and the time on bypass.

Objectives: The current study was performed to establish the prevalence rate of hearing disorders in school age children.
Method: This study has been performed in a randomized manner among 1000 school-age children (500 girls and 500 boys) in the years between1976-1997 in Behbehan. All subjects underwent Audiometric evaluations, Otoscopy, and impedance audiometry. Additionally, parents, children and teachers were interviewed or asked by questionnaires regarding the familial status of parents, familial history of any hearing loss and the awareness of suffering hearing loss. The findings have been prepared in the charts and tables and the relationship between age and gender of the subjects with the incidence of hearing loss has been evaluated via the statistical test X² and hearing loss in left and right ear was compared by T-test.
Results: the findings demonstrated that 6.6% of the subjects suffered hearing loss in one ear (2.2%) or both ears (4.3%). 4.8% of the patients suffered conductive hearing loss while 1.6% suffered sensory-neural hearing loss. In .2% patients complained different types of hearing loss in the ears. Hearing loss was mostly slight and the relationship between age and gender with the incidence of hearing loss was not statistically significant.
Conclusion: Based on the findings we have concluded that in18.4% of the subjects, medical treatment was required and 0.7% of them were in need of rehabilitation. The percentage of the awareness of the hearing disorders among children, parents and teachers was 21.2%, 22.7% and 15.2% respectively.