Ahmet Atas
Hacettepe University
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Otology & Neurotology | 2009
Levent Sennaroglu; Ibrahim M. Ziyal; Ahmet Atas; Gonca Sennaroglu; Esra Yucel; Sebnem Sevinc; Meltem Çiğdem Ekin; Sarp Sarac; Gamze Atay; Burce Ozgen; Ozcan Oe; Erol Belgin; Vittorio Colletti; Ergin Turan
Objective: The aim of our study is to present the results of 11 children where auditory brainstem implantation (ABI) was successfully performed to restore hearing. Study Design: Case presentation. This study was conducted at the departments of Otolaryngology and Neurosurgery at Hacettepe University Ankara, Turkey. Patients: Between July 2006 and April 2008, 11 prelingual (30-56 mo) deaf children with several cochlear malformations had ABI. Intervention: All patients were programmed and were enrolled in auditory verbal therapy sessions and family counseling programs at Hacettepe Auditory Verbal Center. The evaluation was performed at preimplant and again 1, 3, 6, 9, and 12 months post-switch on. Main Outcome Measures: The main test components composing this test battery were Ling 6 Sound Detection-Identification Test, Word Identification Test in Turkish, Meaningful Auditory Integration Scale, and Meaningful Use of Speech Scale. Results: Successful brainstem implantations were performed in all patients with retrosigmoid approach. Six children gained basic audiologic functions and were able to recognize and discriminate sounds, and many could identify environmental sounds such as a doorbell and telephone ring by the third month of ABI. Improvement in mean performance on Meaningful Auditory Integration Scale is apparent for all ABI children. Improvement in Meaningful Use of Speech Scale scores in 2 patients, demonstrating that the child using its own voice for speech performance, was observed between the baseline and 12th month. First, 5 children were able to identify Lings 6 sound by the end of 2 to 6 months, and 2 of them also started to identify words due to their pattern differences and multisyllabic word identification by 6 to 9 months. Two children with Attention Deficit Hyperactivity Disorder have made slower progress than the other children with ABIs. Conclusion: Our preliminary results show that there is adequate contribution of brainstem implants in the development of auditory-verbal skills. Additional handicaps slow the progress of the prelingually deaf children.
Otology & Neurotology | 2011
Levent Sennaroglu; Colletti; Manuel Manrique; Roland Laszig; Erwin Offeciers; Saeed S; Ramsden R; Sarp Sarac; Andersen Hr; Andrzej Zarowski; Ziyal I; Sollmann Wp; Kaminsky J; Bejarano B; Ahmet Atas; Gonca Sennaroglu; Esra Yucel; Sevinc S; Colletti L; Huarte A; Henderson L; Wesarg T; Konradsson K
On the 18th of September 2009, a group of health care professionals and scientists involved in implantation of the auditory system attended a meeting convened by the Hacettepe Cochlear Implant Group. The aim of the meeting was to have a detailed discussion on the pressing and pertinent issues around
Pediatric Infectious Disease Journal | 2002
Kanra G; Ates Kara; Ali Bulent Cengiz; Pinar Isik; Mehmet Ceyhan; Ahmet Atas
Sensorineural hearing loss is an important complication of mumps. Audiologic tests of 26 children with mumps meningoencephalitis, 25 uncomplicated mumps cases and 20 control cases were performed, and hearing level thresholds at speech and high frequencies were determined. The mean hearing level thresholds in the mumps meningoencephalitis group were higher than those of mumps cases at frequencies from 6,000 to 18,000 Hz in the right ear and at 250 and from 4,000 to 18,000 Hz in the left ear (P < 0.05). Mumps meningoencephalitis cases had higher mean hearing thresholds than did control groups at all frequencies other than 125 and 250 Hz in the right ear and 10,000 Hz in the left ear. The mean hearing thresholds of mumps cases were higher than those of control group at frequencies of 1,000 and 4,000 Hz in the right ear and 1,000 and 10,000 Hz in the left ear (P < 0.05). These results show that mumps meningoencephalitis causes a higher risk of hearing loss than does mumps.
International Journal of Pediatric Otorhinolaryngology | 2009
Fulya Yalçınkaya; Nuray Bayar Muluk; Ahmet Atas; Robert W. Keith
OBJECTIVES In auditory neuropathy (AN) children with hearing aids (HAs) or cochlear implant (CI), the speech perception improvement may not be in a significant degree. These children may perform speech perception after a few repeats. This condition may show that these children had difficulties in receiving and processing speech sounds. If the children with AN cannot distinguish the heard tones one or two in Random Gap Detection Test (RGDT), their benefit performances between hearing aids or CI may not be significant. It is thought that the answer of this question is closely related with unique auditory processing performance of each child. The aim of the study is to investigate the RGDT and RGDT-Expanded (RGDT-EXP) performance of five children with AN. METHODS In this study, RGDT was applied to five children with auditory neuropathy between ages of 7 and 13 years (study group) (3 male, 2 female). As a control group, RGDT was applied to 10 normal hearing children who had not auditory processing problem between ages of 7 and 16 years (5 male, 5 female). In the first test, all children were applied to RGDT and RGDT-EXP. Each child responded whether he/she heard one or two tones. Their responses were taken as verbally and/or hold up one finger or two fingers. In the second test, they were applied speech discrimination test in quiet environment and in noise. Gap detection thresholds (GDTs) were detected at 500-4000 Hz; and composite GDTs (CGDTs) were found for the study and control groups. GDT/CGDT>20 ms was considered as abnormal for temporal processing disorder. RESULTS Any of the children with AN who has no HAs; with HAs; and CI, could not be able to perform RGDT. Therefore the RGDT-EXP was applied in this group. In the study group, GDTs was all over 50 ms at 500-4000 Hz; and CGDTs were all over 50 ms for all children included into the study group with AN. In control group, except child 9 (GDTs were 25 ms at 3000 and 4000Hz); and child 10 (GDT was 25 ms at 500 Hz); GDTs were all in normal limits for 500-4000 Hz for all children included into the study as control group. CGDTs were all in normal limits for the control group, except child 9 (CGDTs were 22.50, slightly higher than normal limits). In the study group with AN, mean of the GDTs was all over the normal limits; and in control group, mean of GDTs were all in normal limits. The difference between the mean GDTs of the study group was significantly higher than the control groups at all frequencies of 500-4000. In AN group, CGDT (97.5+/-9.57 ms) was significantly higher than that of the control group (10.35+/-0.65 ms). CONCLUSION We concluded that these results may only not be explained by auditory processing performance or temporal aspects of audition of each child. Their gap detection was much worse for short duration stimuli than for longer duration stimuli. The present study showed that temporal processing, auditory timing and gap detection skills of the children with AN were found as delayed in advanced degree. These findings may indicate that the AN children cannot perform temporal asynchrony. Our results may help to understand why the children with AN cannot manage the speech perception; and why they understand the speech after a few repeats.
Otology & Neurotology | 2011
Betul Cicek Cinar; Ahmet Atas; Gonca Sennaroglu; Levent Sennaroglu
Objective: The aim of the study was to compare results of objective test techniques in cochlear implant users with inner ear malformations and incomplete partition anomalies with types I and II and to show which techniques should be used in the evaluation and fitting of cochlear implant users with inner ear malformations. Study Design: Retrospective clinical study. Patients: The subjects in the control group were selected randomly from cochlear implant users with normal cochlea. Inclusion criteria for patients group were having inner ear malformation for the study group and at least 1 year cochlear implants use for both groups. Interventions: For each individual subject, electrically evoked compound action potentials (ECAPs), electrically evoked stapedius reflex threshold (ESRT), and electrically evoked auditory brainstem response (EABR) thresholds were determined. These tests were applied after a normal cochlear implant fitting session. There were 20 subjects in inner ear malformation group and 15 subjects in the control group. For each subject, 6 intracochlear electrodes, representing apical, middle, and basal array of intracochlear electrode, were used. Main Outcomes: In the cochlear malformation group, percentage of acquired ECAP thresholds was 25%. However, in the control group, percentage of ECAP was 74%. Similarly with ECAP, percentage of ESRT in the cochlear malformation group was 17.5%, and that in the control group was 90%. The difference between these percentages was statistically significant. Both current levels and latencies of EABR wave V were significantly different from each other for the inner ear malformation group and the control group. Results: For statistical analysis, Mann-Whitney U test for 2 independent samples, Kruskal-Wallis analysis and Dunns Z test were used. Conclusion: For the inner ear malformation group, EABR is a more applicable objective test technique when compared with ECAP and ESRT.
Ear and Hearing | 2011
Martin O'Driscoll; Wael El-Deredy; Ahmet Atas; Gonca Sennaroglu; Levent Sennaroglu; Richard T. Ramsden
Objectives: The inclusion criteria for an auditory brain stem implant (ABI) have been extended beyond the traditional, postlingually deafened adult with Neurofibromatosis type 2, to include children who are born deaf due to cochlear nerve aplasia or hypoplasia and for whom a cochlear implant is not an option. Fitting the ABI for these new candidates presents a challenge, and intraoperative electrically evoked auditory brain stem responses (EABRs) may assist in the surgical placement of the electrode array over the dorsal and ventral cochlear nucleus in the brain stem and in the postoperative programming of the device. This study had four objectives: (1) to characterize the EABR by stimulation of the cochlear nucleus in children, (2) to establish whether there are any changes between the EABR recorded intraoperatively and again just before initial behavioral testing with the device, (3) to establish whether there is evidence of morphology changes in the EABR depending on the site of stimulation with the ABI, and (4) to investigate how the EABR relates to behavioral measurements and the presence of auditory and nonauditory sensations perceived with the ABI at initial device activation. Design: Intra- and postoperative EABRs were recorded from six congenitally deaf children with ABIs, four boys and two girls, mean age 4.2 yrs (range 3.2 to 5.0 yrs). The ABI was stimulated at nine different bipolar sites on the array, and the EABRs recorded were analyzed with respect to the morphology and peak latency with site of stimulation for each recording session. The relationship between the EABR waveforms and the presence or absence of auditory electrodes at initial device activation was investigated. The EABR threshold levels were compared with the behavioral threshold (T) and comfortably loud (C) levels of stimulation required at initial device activation. Results: EABRs were elicited from all children on both test occasions. Responses contained a possible combination of one to three peaks from a total of four identifiable peaks with mean latencies of 1.04, 1.81, 2.61, and 3.58 msecs, respectively. The presence of an EABR was a good predictor of an auditory response; however, the absence of the EABR was poor at predicting a site with no auditory response. The morphology of EABRs often varied with site of stimulation and between EABR test occasions. Postoperatively, there was a trend for P1, P3, and P4 to be present at the lateral end of the array and P2 at the medial end of the array. Behavioral T and C levels showed a good correlation with postoperative EABR thresholds but a poor correlation with intraoperative EABR thresholds. Conclusions: The presence of an intraoperative EABR was a good indicator for the location of electrodes on the ABI array that provided auditory sensations. The morphology of the EABR was often variable within and between test sessions. The postoperative EABR thresholds did correlate with the behavioral T and C levels and could be used to assist with initial device fitting.
European Journal of Pediatrics | 2002
Kanra G; Ates Kara; Seçmeer G; Hasan Özen; Figen Gürakan; Zuhal Akçören; Ahmet Atas
Abstract. Inflammatory bowel disease is becoming increasingly frequent in children of all ages. In addition to the usual gastrointestinal stigmata of weight loss, anaemia, and rectal bleeding, children may exhibit prominent extra-intestinal manifestations such as joint symptoms, skin signs and some other auto-immune manifestations. Here we present a 15-year-old girl with ulcerative colitis in whom pyoderma gangrenosum and acute sensorineural hearing loss developed. Conclusion: although pyoderma gangrenosum is well described with inflammatory bowel disease, sensorineural hearing loss a is very unusual finding, possibly of auto-immune aetiology. We recommend steroid or immunosuppressive therapy in such a patient.
Otology & Neurotology | 2016
Levent Sennaroglu; Gonca Sennaroglu; Esra Yucel; Bilginer B; Gamze Atay; Bajin; Mocan Bö; Yaral M; Aslan F; Çnar Bç; Özkan B; Batuk Mö; Kirazl Çe; Karakaya J; Ahmet Atas; Sarp Sarac; Ziyal I
Objective: To report the long-term outcomes of children who received auditory brainstem implant (ABI) because of severe inner ear malformations. Study Design: Retrospective chart review. Setting: Tertiary referral otolaryngology clinic. Subjects and Methods: Between July 2006 and October 2014, 60 children received ABI at Hacettepe University. Preoperative work up included otolaryngologic examination, audiological assessment, radiological evaluation together with assessment of language development and psychological status. The surgeries were performed via retrosigmoid approach with a pediatric neurosurgeon. Intraoperatively, electrical auditory brainstem response was utilized. Initial stimulation was done 4 to 5 weeks postoperatively. Outcomes were evaluated with Categories of Auditory Performance (CAP), speech intelligibility rate (SIR), functional auditory performance of cochlear implant (FAPCI) and Manchester Spoken Language Development Scale scores; receptive and expressive language ages were determined. Results: Sixty children who received ABI were between ages of 12 and 64 months. Thirty-five patients with follow up period of at least 1 year, were reported in means of long-term audiological and language results. The most prevelant inner ear malformation was cochlear hypoplasia (n = 19). No major complication was encountered. Majority of the patients were in CAP 5 category, which implies that they can understand common phrases without lip reading. SIR was found out to be better with improving hearing thresholds. Children with ABI were performing worse than average cochlear implantation (CI) users when FAPCI scores were compared. Patients with the best hearing thresholds have expressive vocabulary of 50 to 200 words when evaluated with Manchester Spoken Language Development Scale. There was no relationship between the number of active electrodes and hearing thresholds. The type of inner ear anomaly with the best and the worst hearing thresholds were common cavity and cochlear aperture aplasia, respectively. Patients with additional handicaps had worse outcomes. Among 35 children, 29 had closed set discrimination and 12 developed open set discrimination above 50%. It was determined that, progress of the patients is faster in the initial 2 years when compared with further use of ABI. Conclusion: ABI is an acceptable and effective treatment modality for pediatric population with severe inner ear malformations. Bilateral stimulation together with CI and contralateral ABI should be utilized in suitable cases.
American Journal of Otolaryngology | 2008
Fulya Ozer; Ömer Faruk Ünal; Ahmet Atas; Ozgül Tekin; Arzu Sungur; Kıvanç Ayas
PURPOSE The aim of this study was to investigate the audiological and histopathologic effects of dexamethasone in the treatment of experimentally induced endolymphatic hydrops. MATERIALS AND METHODS Thirty mature, male guinea pigs weighing 400 +/- 50 g were operated on to induce experimental endolymphatic hydrops in their right ear. Left ear served as control. Subjects were separated into control and dexamethasone groups, with the latter receiving dexamethasone 5 mg/(kg d) intraperitoneally for 10 days. Electrocochleography and auditory brainstem response were applied to all subjects at preoperation, on the second postoperative day and also on the 15th postoperative day in animals that lived for a long time. The histopathologic examination of the inner ear in all animals was done at the end of the study. RESULTS The summating potential and the ratio of the summating potential to the action potential measured on the second postoperative day were found to be increased in both groups, but more significantly in the control one. When the left and right ears were compared, significant difference was found in the control group; however, no significant difference was found between the ears in the dexamethasone group. Histopathologic examination revealed varying degrees of hydrops in the control group, but showed only normal findings or minor changes in the dexamethasone group. CONCLUSIONS Dexamethasone can prevent the audiological and histopathologic findings of experimentally induced endolymphatic hydrops. However, these results must be supported by clinical and experimental studies designed with a large number of subjects.
Cochlear Implants International | 2016
Levent Sennaroglu; Vittorio Colletti; Thomas Lenarz; Manuel Manrique; Roland Laszig; Helge Rask-Andersen; Nebil Göksu; Erwin Offeciers; Shakeel Saeed; Robert Behr; Yildirim A. Bayazit; J. W. Casselman; Paul R. Kileny; Daniel J. Lee; Robert V. Shannon; Mohan Kameswaran; Abdulrahman Hagr; Andrzej Zarowski; Mark S. Schwartz; Burcak Bilginer; Ameet Kishore; Gonca Sennaroglu; Esra Yucel; Sarp Sarac; Ahmet Atas; Lilian Colletti; Martin O'Driscoll; In Seok Moon; Lutz Gärtner; Alicia Huarte
Consensus statement : Long-term results of ABI in children with complex inner ear malformations and decision making between CI and ABI