Methods and Materials: Investigation of electrically evoked auditory brain stem response (EABR) is a new issue, especially in implanted patients. Experiments were performed in C.I Center of Iranian Institute for Science and research expansion,1996 on 30 implanted patients with 22 spectra and MSP cochlear implant system and 30 normal subjects with the range of 3-33 years.Findings:1- EABR was obtained in the implanted patients.2- Absolute latency of EABR waves is 1-1.5 ms shorter than ABR waves ‘P<0.05).3-Absolute latency of wave V decreases as a function of electric stimulus magnitude (P<0.05).4- No significant difference was observed in IPL Ill-V between ABR and EABR.

Background and Aim: Auditory neuropathy (AN) can be diagnosed by abnormal auditory brainstem response (ABR), in the presence of normal cochlear  microphonic (CM) and otoacoustic emissions (OAEs).The aim of this study was to investigate the ABR and other electrodiagnostic test results of six patients suspicious to AN with problems in speech recognition.
Materials and Methods: this cross sectional study was conducted on 6 AN patients with different ages evaluated by pure tone audiometry, speech discrimition score (SDS) , immittance audiometry , electrocochleography , ABR, middle latancy response (MLR), late latency response (LLR), and OAEs.
Results: Behavioral pure tone audiometric tests showed moderate to profouned hearing loss. SDS was so poor which is not in accordance with pure tone thresholds. All patients had normal tympanogram but absent acoustic reflexes. CMs and OAEs were within normal limits. There was no contralateral suppression of OAEs. None of cases had normal ABR or MLR although LLR was recorded in 4.
Conclusion: All patients in this study are typical cases of auditory neuropathy. Despite having abnormal input, LLR remains normal that indicates differences in auditory evoked potentials related to required neural synchrony. These findings shows that auditory cortex may play a role in regulating presentation of deficient signals along auditory pathways in primary steps.

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.

Background and Aim: In neural response telemetry (NRT), intracochlear electrodes stimulate the auditory nerve and record the neural responses. The electrical stimulation send to the auditory nerve by an electrode and the resulted response, called electrically evoked compound action potential (ECAP), is recorded by an adjacent electrode. The most important clinical applications of this test are evaluation and monitoring the intra and postoperative responses of auditory nerve and help to primary setting of speech processor. The aim of this study was evaluating of the potential&aposs threshold changes in three monthes after receiving the devise in pediatric cochlear implant recipients.
Materials and Methods: This longitudinal study evaluated the potential&aposs threshold in four given electrodes in four sessions after receiving the device by approximately one months intervals in children implanted in Amir Alam and Hazrat-e-Rasoul hospitals in 2007, July to December.
Results: ECAP mean threshold level of each electrode did not significantly change in differnent sessions, while there was significant difference between apical and basal electrodes&apos responses in every session(p<0.001).
Conclusion: The reliabiliy of the responses result in more certainty of clinician to fit the speech processor for a long time. Better responses in apical electrodes may lead to develope an effective coding strategy.

Background and Aim: Patients with systemic lupus erythematosus (SLE) may develop hearing and balance disorders as a result of the immune-mediated inner ear damage. Vestibular evoked myogenic potential (VEMP) is a new vestibular test assesses the vestibulospinal tract. Balance disorders such as endolymphatic hydrops may occur as a result of perisaccular deposition of immune complexes in these patients. Although the vestibular system abnormality in the patients has been demonstrated, the function of the part of vestibular system including vestibulospinal tract has not been investigated so far. This study aimed to compare the vestibular evoked myogenic potentials between patients with inactive stage of systemic lupus erythematosus and normal individuals.

Methods: In this cross-sectional study, vestibular evoked myogenic potential was recorded between 26 healthy subjects and 20 patients with lupus erythematosus in inactive stage of disease aged 20 to 50 years old, using 500 Hz-tone bursts at 95 dB nHL.

Results: Vestibular evoked myogenic potentials responses were present in all (100%) of the participants. There was no significant difference in mean peak to peak amplitude and assymetry ratio between two groups. The mean p13 and n23 latencies were significantly higher in patients (p<0.05). Duration of disease had no effect on test parameters.

Conclusion: According to the prolonged latency of vestibular evoked myogenic potentials response in patients with lupus erythematosus , lesions in the retrolabyrinthine, especially in the vestibulospinal tract is suspected. Due to small sample size, there is no possibility for generalizing this result to all patients with lupus lupus erythematosus .