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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.

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Auditory perceptual and visual-spatial characteristics of subjective tinnitus evoked by eye gaze were studied in two adult human subjects. This uncommon form of tinnitus occurred approximately 4-6 weeks following neurosurgery for gross total excision of space Occupying lesions of the cerebellopontine angle and hearing was lost in the operated ear. In both cases, the gaze evoked tinnitus was characterized as being tonal in nature, with pitch and loudness percepts remaining constant as long as the same horizontal or vertical eye directions were maintained. Tinnitus was absent when the eyes were in a neutral head referenced position with subjects looking straight ahead. The results and implications of ophthalmological, standard and modified visual field assessment, pure tone audio metric assessment, spontaneous otoacoustic emission testing and detailed psychophysical assessment of pitch and loudness are discussed.

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Objectives: we were aimed at studying the difference in the effect of noise and pure tone on the residual inhibition in patients suffering tinnitus.
Method: patients were selected among whom referred to audiology clinic in Ran faculty of rehabilitation sciences and aged between 20-70 years old. Our method in studying patients was experimental- masking with pure tone was performed in patients who had experienced partial residual inhibition with noise.
Results the differences between the masking methods was not statistically significant.
Conclusion: it seems that no significant differences exist between the two mentioned methods in masking tinnitus.

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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.

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A 34-year-old female with a history of a sudden mild left-sided hearing loss and high-pitched tinnitus along with fullness in the same ear was referred to the audiology clinic. Hearing fluctuation and variability in other symptoms were also reported. Although no complain of any vertigo or balance disorder was mentioned, light headedness was implied. Differential diagnosis of endolymphatic Fistula and retro cochlear lesion was demanded. Audiologic and radiologic findings of this patient are presented in the article to discuss findings regarding the diagnosis of the suspected disorder.

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In the current investigation we gathered information about the hearing thresholds, types of hearing loss, types of tinnitus, and also the prescribed tinnitus maskers for the veterans. We were aimed at determining the percentage of tinnitus, audiogram shape and its relationship with tinnitus, and the percentages of veterans using tinnitus maskers. The needed information was prepared by studying the audiograms and file of the patients.  The results of the investigation have been prepared here in details.

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Tinnitus from the Latin word tinnire meaning ringing is the perception of sound within the human ear in the absence of corresponding external sound. The most common cause is noise induced hearing loss. Tinnitus may be induced by an acoustic trauma or a permanent noise in the workplace. In case that Tinnitus is induced by acoustic trauma the site of lesion is commonly the base of the cochlea. Tinnitus in the senile population is mostly accompanying presbycusis. Although the incidence of permanent tinnitus following noise exposure is high, little is published about this issue. In the current article we are aimed at studying the prevalence of tinnitus in Minoo and other manufactures.

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Vestibular Schowanoma is one of the most common Intracranial Tumors which has elicited from the Schwann cells in the upper part of vestibular branch of 8^th nerve and can affect the cochlear branch too. This benign capsulated tumor  is mostly unilateral. Schowanoma is relatively slow growing.In the current article we have presented the case of a 51 year-old woman complaining Right ear Tinnitus accompanying with numbness of the right side of the face without any sign of vertigo or imbalance. MRI and Auditory Brain stem Responses (ABR) studies demonstrated right side vestibular Schowanoma next to cerebellopontine Angle (CPA). The audiological and imaging findings have been brought here in details.

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Background and Aim: Tinnitus represents the perception of sound without an external stimulus. The prevalence of tinnitus ranges from 3% to 30%. In most cases its etiology is unknown. Tinnitus can be classified as pulsatile or nonpulsatile. Nonpulsatile form is the most common form and almost exclusively subjective in nature.  There is a range of condition attributed to nonpulsatile high frequency tinnitus (acoustic neuroma,  Meniere&aposs disease, ototoxic agents, noise exposure...). There are many studies about form, site, loudness, and frequency of tinnitus and how it can affect the quality of patient life.
Materials and methods: This was a descriptive and analytic study. Thirty-six patients (23 men and 13 women) with mean age 53.1 year old with subjective tinnitus evaluated in pezhvak audiometric clinic in Mashhad .The data consisting of age sex, loudness, frequency form and site of tinnitus. Evaluation of affects of tinnitus on the quality of life and habits was performed with a tinnitus questionnaire (TQ).
Results: Tinnitus was unilateral in 64% of cases right site was more common. Mean  pitch was 7.03 kHz and average loudness was 3.8 dB SPL. SDS was in normal range in all of patients. There was a high frequency sensory neural hearing loss (above the 4 kHz) in most of the patients. The greatest score (60.3%) of TQ related to intrusiveness aspect. Sleep disorder has the lowest score (39/3%). Global score was 52.4%.
Conclusion: Nonpulsatile subjective tinnitus has a broad range of etiology with unknown mechanism in most cases and without any history of underlying disease in a large group of patients. This symptom mostly involves the patients` lifestyle that is intrusiveness aspect in comparison with the other aspects including sleep, hearing and somatic complaints. There is no cure for most patient and more studies are needed in the future.

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Background and Aim: Tinnitus is the consciousness of sound that arises in the ear or head without any external sound origin. The efficacies of transmeatal low-level laser irradiation for tinnitus treatment were reported before. The aim of this study was to evaluate the effectiveness of low level laser therapy on tinnitus and ECochG and DPOAEs parameters.
Materials and Methods: The study design was prospective, quasi experimental. This investigation conducted on 16 ears (10 patients) with disabling tinnitus. All patients underwent ENT examination, complete audiological evaluation, tinnitus study, ECochG and DPOAEs, and finally completing tinnitus data sheet. The results were compared before and after irradiation.
Results: Means of tinnitus loudness (LMT) and CAP amplitudes were significant different before and after irradiation (p<0.005). There was no any other significant difference before and after low level laser irradiation in subjective loudness, pitch matching annoyance grade of tinnitus and DPOAEs and other ECochG parameters.
Conclusion: Transmeatal low-power laser irradiation with 200 mW seems not to be effective for treatment of tinnitus. This paper is the research brief report. In clinical point of view, this study should be repeated with a greater sample size although our results were statistically important.

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Background and Aim: Tinnitus is a common symptom among lots of people but little is known about its origins. This study was aimed at comparing the Auditory Steady-State Response (ASSR) thresholds in normal cases and patients with subjective idiopathic tinnitus (SIT) in order to diagnose its real origins.
Materials and Methods: This case-control study was conducted on 19 patients with tinnitus and 24 normal cases aged 18-40 yr.The patients underwent broad medical tests to roll out any background reason for their tinnitus. ASSR thresholds were estimated in both groups at 20 and 40 amplitude modulation. The patients were selected from tinnitus patients in Research Center in Hazrat Rasoul Hospital, Tehran, Iran.
Results: The mean ASSR thresholds at 40HZ modulation were worse in tinnitus patients compared to normal ones (p<0.05) but no significant statistical differences was detected at 20HZ. These results were found in both situations in which we averaged both ears thresholds and when we estimated the thresholds of the ears separately.
Conclusion: It seems that the origin of the responses of the modulation of 40Hz, primary auditory cortex, midbrain regions and subcortical areas, in these patients is involved or the origin of their tinnitus is related to some kind of problems in these areas, although more investigation is needed about 20Hz.

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Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR) were compared in noise induced tinnitus and non-tinnitus control subjects.
Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.
Results: Mean interpeak latencies of III-V (p= 0.022), I-V (p=0.033) in ipsilatral electrode array and mean absolute latencies of IV (p=0.015) and V (p=0.048) in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group.
Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

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Background and Aim: Tinnitus is an annoying disease cause major problems including insomnia, impaired concentration, and reduced quality of life. This study aimed to investigate the effectiveness of hypnotherapy in the treatment of subjective tinnitus.
Methods: This was a pilot experimental study with pre- and post-test method. 20 people suffered from subjective tinnitus were divided equally in two groups of experimental and control. The two groups were matched according to age and severity of tinnitus. They completed tinnitus clinical questionnaires before and after the test and the severity of their tinnitus was recorded by a number from one to ten. Experimental group went under hypnotherapy for 10 sessions. The control group did not perform any psychological treatment. The gathered data were statistically analyzed using Student&aposs t-test (independent and dependent).
Results: There were significant differences between the pre-test and post-test scores of each group and also, between the post-test scores of experimental and control groups (p = 0.001 for all).
Conclusion: The results showed that hypnotherapy could effectively reduce the seventy of tinnitus in patients in the experimental group in other words, the results confirm the effectiveness of medical hypnosis in the treatment of subjective tinnitus.

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Background and Aim: Subjective tinnitus etiology has not been fully understood. Recently, in normal hearing subject one of the tinnitus theories, more specifically the medial olivocochlear tract, is related to the dysfunction of the efferent auditory system. The aim of this study was to determine the potential contribution of a defective cochlear efferent innervations to the chronic tinnitus in patients with normal hearing and determine the relation between tinnitus loudness and the amount of suppression of the transient evoked otoacoustic emission. Methods: This study was conducted on 20 tinnitus patients aged between 20-45 years and 20 controls matched for age and gender in School of Rehabilitation, Tehran University of Medical Sciences. Transient otoacoustic emission testing without and with contralateral white noise at 55 and 65 dB was performed on each subject. Results: The amplitudes of the emissions in the two groups was significantly different (p=0.001), but no correlation between tinnitus loudness and the amplitudes of the emissions in the presence (p=0.3) and absence (p=0.06) of contralateral noise. Conclusion: The suppression of the transient evoked otoacoustic emission by contralateral white noise did not reach statistically significant levels in tinnitus patients while the amplitude in control group reduced significantly.

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Background and Aim: While most of the people with tinnitus have some degrees of hearing impairment, a small percent of patients admitted to ear, nose and throat clinics or hearing evaluation centers are those who complain of tinnitus despite having normal hearing thresholds. This study was performed to better understanding of the reasons of probable causes of tinnitus and to investigate possible changes in the auditory brainstem function in normal-hearing patients with chronic tinnitus.

Methods: In this comparative cross-sectional, descriptive and analytic study, 52 ears (26 with and 26 without tinnitus) were examined. Components of the auditory brainstem response (ABR) including wave latencies and wave amplitudes were determined in the two groups and analyzed using appropriate statistical methods.

Results: The mean differences between the absolute latencies of waves I, III and V was less than 0.1 ms between the two groups that was not statistically significant. Also, the interpeak latency values of waves I-III, III-V and I-V in both groups had no significant difference. Only, the V/I amplitude ratio in the tinnitus group was significantly higher (p=0.04).

Conclusion: The changes observed in amplitude of waves, especially in the latter ones, can be considered as an indication of plastic changes in neuronal activity and its possible role in generation of tinnitus in normal-hearing patients.