The disastrous effects of Hearing loss on speech and language development can be minimized by early interventions. Profoundly deaf or hard of hearing children not benefitting enough from other kinds of hearing aids are referred for surgically implanted electronic cochlear implant that provides a sense of sound or comprehension of speech. Evaluation and management of pediatric patients is performed by cochlear implant team which consists of different specialists and doctors. Selecting children for the implant surgery is performed based on the certain criteria suggested by Staller et. al. in 1991. All the patients undergo comprehensive medical and Audiological evaluations before the surgery.In this article we will review different process of cochlear implant surgery and pre- surgery Audio logical evaluations in brief.

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).

We designed this study to measure the Percussion caused by pneumatic drill( 32gram) which is used commonly in different in city services. this study have been performed in the summer of 1375 in Hamedan. The results demonstrated that the average background noise level (including environment and compressor) was 92.4 with standard deviation of 5.4 dBC, the average background noise level of the drills while working was 109.6 dBC with the standard deviation of about 2.2dBC and the average peaking factor was 18.6 with a standard deviation of 3.7dBC. the average background noise level of the drills while working in a distance of 5m, 10m and 20m from the source respectively were 98.6 dBA(with a standard deviation of 2.8dBA), 91.5dBA(with a standard deviation of2.6dBA) and 86.8dBA with a standard deviation of 2.8dBA).Based on the obtained results and the potential effects of exposure to noise which mainly can be summarized to damage to auditory system, interference with the communication skills, neural excitation, Hypertension and tachycardia the side effects of noise should be taken in to account seriously.Based on the mounting evidences regarding the adverse impact of working in the noisy environment and the damaging consequences of living in such atmospheres and the findings of the current study which confirms that the noise exposure level is more than allowed limit, the health of the workers and citizens is threaded by the noise pollution factors mentioned in the current study and serious considerations should be taken in to account.

There are increasing evidences about the vestibular damage caused by the exposure to noise. Histological and functional derangements of the vestibular system have been reported in laboratory animals exposed to high levels of noise. However, clinical series describe contradictory results with regard to vestibular disturbances in industrial workers and military personnel suffering from noise induced hearing loss (NIHL). Animal studies have proved that crista ampullaris bears the most disturbances, though some damages have been also detected in macula of the utricle and saccule and utricle. These changes have been induced due to acoustical pressure on the vestibular labyrinth. The findings from the experiments regarding vestibular function in patients suffering NIHL have shown a paramount diminish in vestibulo-occular Reflex (VOR). The correlation among NIHL, VOR and unilateral caloric weakness were statistically significant which can be due to a common mechanism of disturbances in the function of cochlea and vestibule.

We expect some people benefit more from their hearing aids, but after a while they complain of inappropriate loudness growth.  Currently fitting hearing aids based on their loudness growth curves one of the best and most acceptable ways of fitting hearing aids we should study this curve based on the disturbed function of inner and outer hair cells. We should also know that based on which curves can make the growth curve of the damaged cells to normal ones.

The major focus of this research is on the differential disruption of language abilities subsequent to brain damages as they relate to site and size of lesion, especially left hemisphere lesions which disrupt the production and processing of "Nouns" vs. "Verbs" as two functionally different lexical categories. Several clinical as well as experimental studies reported on different language have shown that nouns and verbs can be independently disrupted due to brain damage. A prevalent impairment in naming actions (Producing verbs) is reported in non-fluent aphasic patients, with lesions involving left frontal lobe, whereas a selective in naming objects (Producing nouns) has been observed in amnesic patients, with lesions involving the temporal lobe and the temporal lobe and the posterior association aresas. This research is a theoretical and fundamental based on descriptive and analytical method. The aphasic data in this research were obtained by assessing each patient&aposs aphasic symptoms using a standard Persian aphasia test (Paradis, Nilipoure, Paribakht, 1989) as well as post-test analysis of each patient&apos connected descriptive speech. The subjects were selected form among aphasics who referred to speech therapy centers in Tehran during a pe5iod of one year since autumn 1999. The subjects selected in the study were a homogenous group with left hemisphere lesions due to CVA. They were educated adult right handed. Speakers of Persian without any risk factor such as nicotine, alcohol or any addiction and diabetes with no gross depression or anxiety problems or face and oral paralysis and hemiaopsia. The subjects in this study comprised to adults ranging between 33 and 76 years of age. The results indicated that there are significant correlation between: 1) The production of nouns and left hemisphere lesion. 2) The production of verbs and left hemisphere lesion. 3) Brain lesion and language deficits. 4) The site of lesion and language abilities. Although the data are limited and the generalization of the study has certain restrictions, the present data indicate some specific and reliable avidence on the selective impairment of nouns and verbs due to different lesions in the left hemisphere.

In the present longitudinal study, 20 deaf and 20 hearing children were observed during free play with their hearing mothers when the children were 22 months and 3 years of age. Compared to hearing children, deaf children were severely language delayed, with deaf 3-year-olds using less language (speech or sign) than hearing 22-month-olds. Deaf children communicated primarily through nonlinguistic vocalizations, with increasing use of gesture from 22 months to 3 years of age. Although mothers of deaf children used more visual communication than mothers of hearing children, they still primarily communicated through speech. In addition, deaf children did not visually attend to much of their mothers&apos communication. Therefore, deaf children received much less communication than hearing children. These results suggest that intervention efforts should be focused on increasing the quantity of perceived linguistic input by the child.

Objective: Genetic studies show that consanguineous marriage can increase the probability of incidence of genetic impairments such as hearing impairments. The target of this study is to identify the prevalence of consanguinity among the parents of hearing impaired students in primary schools.

Materials and Methods: We selected all of deaf students of Tehran (614 students). Their mothers answered to questionnaires. The questions were about Risk Factors of deafness in mother pregnancy or in neonatal period.
Results: from 614 students, 389 parents of them (64%) had consanguineous marriage and 223 person (36%) didn&apost have this factor. 2 person did not answer to this question. In this study we observed that there is 32.3% family history of hearing loss, 29.2%deaf sister and brother, 17% ear infection history. Other risk factors were studied too. Also there is significant correlation between consanguinity and more than one deaf children in the family (p<0.005).
Conclusion: According to high incidence of consanguinity (64%)that was observed in this study it may be one of most important causes of sensory neural hearing loss in children, so we should give enough information about this problem to the people.

Background and Aim: In recent years, attention of the health care managers is attracted to three factors including promotion of services quality, accessibility and procurement of financial resources of relevant organizations. The aim of this study is to consider the executive status of guideline of managed health care for preoperative assessments of ENT patients at Bazarganan Hospital in 2005.
Materials and Methods: The present research is conducted on 140 cases in descriptive form. The research information is collected by using a check list. Indexes and method of descriptive statistics are used for the data analysis and statistical study.
Results: Of one hundred and forty ENT patient records, in 136 (97%) of the cases American Society of Anesthesia criteria had been registered. Vital signs, patient histories and CBC were recorded in 137 (98%), 138 (99.5%) and 139 (98.3%) patients recordes, respectively. Eight (69.7%) over 60 years old cases had been X-rayed. EKG has been performed on all fifteen cases over 40 years old. Thirty nine (28%) recordes contained internist and cardiologist counselling.
Conclusions: Assessment of guidline indicates very good status. Application of managed care guidelines of preoperative assessment in ENT surgeries could play a crucial role in reducing complication of ENT surgeries and the improvement of the implication of the guidelines.

Background and Aim: Mismatch negativity (MMN) is one of auditory evoked potentials that occurs about 100-250 ms after stimulus onset. The MMN waveform is elicited by a discriminateable change in a sequence of repetitive homogenous stimuli. This change can be in intensity level, frequency, or duration of auditory stimuli. The purpose of this study was to obtain MMN waveform using tonal stimuli and to investigate its changes during changes in age.
Materials and Methods: The study was prescriptive-analytic cross-sectional. The participants were sixty children aged 4 to 9 year.The Stimuli were at 80 dB pe SPL. A 1000Hz tone and a 1500 Hz tone were used as standard and deviant stimuli, respectively. Probability of deviant stimuli was 20%. Trials were recorded using surface electrode placed at four locations on the head.
Results: The MMN waveform does not exist in 22.5% of the children. Also, determining of MMN peak in 22.5% was not exactly possible. In other subjects, a significant negative correlation was observed between latency of MMN and age, but not for age and amplitude for this negativity.
Conclusion: This study confirms that the MMN may not be seen in normal people. Also there are maturational changes in MMN waveform.

Background and Aim: Middle latency auditory evoked potentials (MLAEPs) development takes longer time than the auditory brainstem response (ABR) development does, which makes them difficult to record in some children. The purpose of this study was to investigate the age effect on characteristics and detection of MLAEPs in children and adults.
Materials and Methods: This cross sectional study was conducted on 15 children aged   7-12 yr and 31 adults aged 20-50 yr with normal peripheral hearing. To investigate precisely, children were divided in two subgroups of older and younger than 10 years old, as well. The MLAEPs amplitudes and latencies were recorded by conventional protocol and compared.
Results: Adult Na mean latency, 20.86 ms, was less than that of children, 22.86 ms, (p=0.0025).  In contrast, the adult Nb mean latency, 44.93 ms, was longer (p=0.0001). Children Nb mean latency was 42.02 ms. There was no significant difference in MLAEP amplitudes and latencies between two children subgroups, although variance was more in younger children.
Conclusion: MLAEPs are reliably recorded after 7 years old. Characteristics of MLAEPs are different in adults and children so that the primary MLAEPs generators have a course of development extending beyond the first decade of life. As those potentials were recorded in all children, it is suggested to be used in their test batteries for hearing evaluation.

Background and Aim: The purpose of the present study was to investigate the effect of vestibulo-proprioceptive stimulations of sensory integration theory on the development of gross and fine motor, language and personal-social functions in a child with agenesis of the corpus callosum.

Case: We report a 10.5 month old boy with agenesis of the corpus callosum. The intervention was administered based on sensory integration theory an hour a week for 20 weeks. The exercise intervention consisted of proprioceptive and linear, sustained and low frequency vestibular stimulations on suspension device and physio roll. A Denver Developmental Screening- II and milestones skill testing was completed pre-intervention and monthly. Post-intervention, age of gross motor, fine motor adaptive, language, and personal-social functions significantly improved. Based on milestones skills, maintenance of gross motor functions (e.g. sitting and quadruped position) improved. The child could roll from side to side and released objects voluntarily. The reaction time to auditory stimulations became less than 2 seconds.

Conclusion: vestibulo-proprioceptive stimulations using the neuroplasticity ability of the central nervous system is effective for development of gross and fine motor, language, and personal-social functions. These exercises can be administered for a child with agenesis of the corpus callosum.

Background and Aim: Hearing impairment affects all aspect of individual life, specially language and communication skills. When hearing impairment is congenital or occurs early in life, the child's ability to learn optimally through audition, will be affected. The aim of this study was to evaluate linguistic skills of preschool hearing impaired children and compare these skills with normal peers.

Methods: This descriptive cross-sectional study was performed on 38 preschool hearing impaired children that the main handicap was severe to profound hearing loss with ability to communicate orally and 28 normal children with the same cultural and social context. Twenty four non linguistic variables including age, gender, the age of entrance of preschool center, number of hearing aids, etc. were obtained by filling a questionnaire and fifteen linguistics variables including number of utterance, morphemes, correct utterance, noun phrase, ambiguous utterance, correct sentences, compound sentences, etc. were collected by some part of TOLD-P-3 test and three complementary questions. Then we compared the data from two groups.

Results: There were significant differences between number of utterance, number of correct mean length utterance, number of well-formed sentences in normal and hearing impaired group (p<0.000). There were no significant difference between unintelligible utterances, repetitive utterances and bad-formed sentences between two groups(p>0.05).

Conclusion: This study showed a severe deficit in linguistic skills in preschool hearing impaired children.

Background and Aim: Agrammatism is a phenomenon of neuropsychological relevance which has been recently investigated from conceptual and empirical aspects. The present study focuses on grammatical deficit in agrammatic aphasia. We evaluated the impairment of correct use of tenses of Persian verbs in agrammatic Broca&aposs aphasia.
Methods: Eight patients (mean age 57 years) participated in this descriptive - analytic study. They were classified as agrammatic Broca&aposs aphasia according to the Persian aphasia test, their CT Scan and MRI reports and other inclusion criteria. All patients but one were monolingual native speakers of Persian (Farsi). The other individual was bilingual whose dominant language was Persian. All subjects had a left unilateral brain lesion for at least one year after the onset of brain damage. The written sentence completion and picture sentence completion tests were designed and performed.
Results: Results do not indicate significant difference between Past Tenses of verb however, comparison of means showed best scores in Simple Past, Past Continuous, Present Perfect and Past Perfect, respectively. A main result of this study was significant difference between the mean of responses to Past Tense in comparison with Present Tense and Future (p=0.02).
Conclusion: Use of tense is impaired in agrammatic Broca&aposs aphasia in Persian. Our findings point out that use of Past Tense is impaired significantly more than the other tenses of verb.

Background and Aim: Understanding and defining developmental norms of auditory comprehension is a necessity for detecting auditory-verbal comprehension impairments in children. We hereby investigated lexical auditory development of Persian (Farsi) speaking children.
Methods: In this cross-sectional study, auditory comprehension of four 2-5 year old normal children of adult&aposs child-directed utterance at available nurseries was observed by researchers primarily to gain a great number of comprehendible words for the children of the same age. The words were classified into nouns, verbs and adjectives. Auditory-verbal comprehension task items were also considered in 2 sections of subordinates and superordinates auditory comprehension. Colored pictures were provided for each item. Thirty 2-5 year old normal children were randomly selected from nurseries all over Tehran. Children were tested by this task and subsequently, mean of their correct response were analyzed.
Results: The findings revealed that there is a high positive correlation between auditory-verbal comprehension and age (r=0.804, p=0.001). Comparing children in 3 age groups of 2-3, 3-4 and 4-5 year old, showed that subordinate and superordinate auditory comprehension of the former group is significantly lower (p<0.05) than the others . Intra-group comparisons revealed no significant difference between nouns, verbs and adjectives (p>0.05), while the difference between subordinate and superordinate auditory comprehension was significant in all age groups (p<0.05).
Conclusion: Auditory-verbal comprehension develop much faster at lower than older ages and there is no prominent difference between word linguistic classes including nouns, verbs and adjectives. Slower development of superordinate auditory comprehension implies semantic hierarchical evolution of words.

Background and Aim: Asking questions is one of the basic skills for getting information. "What", "Who", "Where", "Why", "How much", "How, etc. are question words frequently used for asking questions. Studies on the sequence of acquisition of question words in English speaking children follow a unique sequence. "What" is the first question word used by these children. We aimed to study whether Persian speaking children follow a unique pattern in the acquisition and use of question words as well.
Case: Two normal Persian speaking children (a boy and a girl) who were sent to the kindergarten of Faculty of Rehabilitation Sciences, Iran University of Medical Sciences by their parents were investigated. Children's spontaneous speech from 12 to 36 months was videotaped, and question words were extracted from phonetic transcription of both children's speech. In order to ask a question, both children initially used rising tone with /m/ or /hum/ before saying the first question word. Two first question words were "what" and "where" in both children's speech samples. Asking about the time with the question word /when/ was not appeared in their speech samples until 36 months. These two Persian speaking children also used Wh-question sequentially.
Conclusion: The result of this study was consistent with the results of other studies on English speaking children.

Background and Aim: valid identification, prevention, and treatment of language disorders are a high priority for the speech and language professionals. One method for studying language development is sentence repetition that is faster to implement and analysis than other procedures. The aim of this project was constructing sentence repetition test as a quick measure of grammatical potency in 2.5 to 4 year old children.
Methods: Sentences appropriate for 2.5 to 4 year old children were selected during several stages by speech and language pathologist and linguists. The validity of sentences was assessed by professional masters in this theme. Subsequently, 41 sentences including those with 80% high validity were selected as the test sentences. Appropriate pictures were also provided with sentences. The test was administrated to 72 children in 3 groups (2.5-3, 3-3.5, and 3.5-4 year olds, gender matched). The reliability was administered with a test-retest design across a 2 weeks interval.
Results: Content validity Index for this test was 80%. "Test-retest reliability" was used for reliability of this test. The Interclass correlation coefficient for this test was 0.95 and standard error measurement was 7.45. The average of scores for sentence repetition, between groups was significant (p<0.001, p<0.001, p= 0.014).
Conclusion: This sentence repetition test has the appropriate validity and reliability as well as the capability of proper and quick assessment (screening) of grammatical development in 2.5 to 4 year old Persian speaking children.

Background: Treacher-Collins syndrome is a congenital craniofacial disorder with multiple anomalies. This syndrome affects the maxilla, mandible, eyes, middle and outer ears, and soft palate. Conductive hearing loss due to the deformities of the middle and external ears is prevalent. The characteristics of this syndrome include multiple and serious threats to normal communication development in children. In this study, speech and language features of a Persian speaking child with this syndrome are presented.
Case: The case was an 8-year old girl with Treacher-Collins syndrome and bilateral moderate conductive hearing loss due to atretic canal. In language and speech assessments, moderate hypernasality, numerous compensatory errors and morphosyntactic deficits were observed. There were 13 phonemes that were incorrectly produced at least in one position. Besides, she used 22 types of phonological processes that were abnormal and disappear before the age of three in normal Persian speaking children.
Conclusion: Moderate hearing loss, velopharyngeal incompetency, malocclusion and dental anomalies, attention deficit/hyperactivity disorder (ADHD) and environmental factors resulted in severe speech and language disorders in this case. These disorders affected her academic performance as well. Moderate hypernasality, numerous compensatory errors, and excessive and abnormal use of phonological processes were not presented as prevalent characteristics of Treacher-Collins syndrome in other resources.

Background and Aim: Formant structure and vowel space are the most important acoustic characteristics of speech sounds. The purpose of this study was to determine formant frequency and vowel space in six Persian vowels.
Methods: This cross-sectional descriptive-analytic study was performed on 60 Persian students of Tehran University of Medical Sciences (30 males, 30 females) with their age ranging from 18 to 24 years. The subject articulated six Persian vowels in isolation and data was recorded by real-analyzer software. Then, the first three formant frequency of each vowel was determined for each subject. Vowel formant frequency averages were measured separately for each vowel and each gender. Vowel space was plotted. The difference between F0 in two groups was compared by Leven and independent sample t tests.
Results: Maximum and minimum values of F0 in both group was related to /æ/ and /a/ (135 Hz in males and 239 Hz in females) and /i/ (146 Hz in males and 239 Hz in females). Besides, F0 in females was significantly higher than males (p<0.001). Maximum and minimum values of F1 were related to /æ/ and /i/. Furthermore, maximum and minimum values of F2 were related to /i/ and /u/. Maximum and minimum values of F3 were related to /i/ and /u/.
Conclusion: The lowest vowels were /æ/ and /a/ and the highest was /i/. The frontest was /i/ and the backest was /u/. the spreadest vowel was /i/ and the roundest was /u/.

Background and Aim: Deafness is a heterogeneous disorder induced by genetic and environmental factors. It is the most common hereditary sensory-neural disorder that affects 1/1000 to 1/2000 of the newborns. More than 70% of hearing loss cases are caused by genetic disorders, 85% of which result from nonsyndromic autosomal recessive sensory-neural hearing loss. Up to now, more than 100 genes contributing in hearing loss have been determined. Alteration of these genes may result in hearing loss.
This study was performed to identify the inheritance patterns of deafness and its relation with ethnicity, gender and consanguineous marriages.
Methods: In this survey, data from 356 families affected by hearing loss and referred to welfare organization of Ahvaz during the time were collected based on sex, ethnic groups and relativeness.
Results: The results state a high frequency of autosomal recessive deafness caused by consanguineous marriages within Arab and non-Arab ethnic groups (p<0.05). But no significant difference in gender.
Conclusion: In conclusion, the high frequency of autosomal recessive deafness among the population with a high frequency of consanguineous marriages is considerable. The dominant pattern of deafness observed in this population was autosomal recessive.