와우 전음성 난청

허승덕,소원섭 한국언어치료학회 2012 한국언어치료학회 학술발표대회 논문집 Vol.2012 No.12

정상 삽입 인공와우 전극의 수술 중 감시 3례

허승덕,이상흔,김이혁,정다영 대한치료과학회 2020 대한치료과학회지 Vol.12 No.2

Objective: Cochlear implantation is the process of inserting a very small and soft electrode into the intrascalar. During surgery, the electrode can be kink or failure, and the internal structure of the cochlea can be damaged by the electrode tip. The study aims to retrospectively analyze the electrode-to-tissue impedance(electrode impedance), voltage compliance, stimulation artifact, electrically compound action potential(ECAP) implemented during the surgery to examine the clinical implication with a literature review. Participants & Method: The participants are three 70 to 76-year-old male implantee to whom MedEl's synchrony(Flex 28) implanted to the left ear. Results: The electrode impedance was observed in 1.69 to 8.25 ㏀, the voltage compliance was observed in 0.52 to 2.38 V, and the inter-channel voltage compliance be ranging from 0.11 to 0.38 V, respectively. In each channels, the baseline of the ECAP waveform was consistently observed, and the threshold of ECAP was observed to be ranging from 7.7 to 26.1 qu. Conclusion: In conclusion, intraoperative monitoring of electrode integrity during the surgery, the malfunctioning of the device together with the various issue that stem the surgery process can be discovered, hence resulting in obtaining valuable proof in solving the issues detected.

전기 자극 청신경 복합활동전위: 변인 영향

허승덕 한국재활복지공학회 2014 재활복지공학회논문지 Vol.8 No.1

Electrical compound action potential (ECAP) can be recorded on cochlear implant. This study will investigate stimulation and recording to enhance the efficacy of ECAP. 34 articles was used. We analyzed pulse and stimulating condition, artifact suppression, recording condition. The cathod-leading biphasic pulse was used with as short as possible pulse width and inter phase gap for the efficacy of neural firing, stable threshold and preventing neural degeneration. Around C-level was stimulated to apical, middle and basal turn of cochlea. Artifact was eliminated by forward-masking, template-subtraction technique. For clearer waveform, we need to change distance between stimulating and recording electrode, the gain of amplification, number of average. 전기 자극 청신경 복합활동전위(electrical compound action potential; ECAP)는 인공와우로 청신경을 자극하고 동시에 반응을 기록한다. 이 연구는 인공와우에서 ECAP의 효용성을 높이기 위하여 자극과 기록에 대하여 연구하고자 한다. 대상은 문헌 또는 사례 연구를 제외한 연구 논문 34 편으로 하였다. 연구는 펄스 및 자극 조건, 잡파 억제 및 기록 조건 등을 분석하였다. 효과적인 신경 발화, 안정적인 역치 확인, 신경 퇴행 방지 등을 위해서는 펄스폭과 위상 간격이 가급적 짧고, (-)위상이 앞선 양위상 펄스를 사용하였다. 자극은 펄스 간격, 자극비율, 자극 방식 등을 정하여 와우의 첨부, 중간, 기저회전으로 C-level 정도로 하였다. 잡파는 전방차폐법, 거푸집소거법으로 제거하였고, 분명한 파형을 획득하기 위해서는 전극 간격, 증폭 정도, 평균 가산 회수 등의 추가 조절이 필요하다.

이명 평가 App 개발

허승덕,이지은,이상흔 한국언어치료학회 2015 한국언어치료학회 학술발표대회 논문집 Vol.2015 No.12

정상 성인에서 청성유발 피부전위

허승덕,정동근,서덕준,김광년,김기련,강명구,김리석,Heo, Seung-Deok,Jung, Dong-Keun,Suh, Duk-Joon,Kim, Gwang-Nyeon,Kim, Gi-Ryon,Kang, Myung-Koo,Kim, Lee-Suk 한국음성학회 2005 음성과학 Vol.12 No.2

Electrodermal activity(EDA) is a bio-electric signal which occurs at the skin surface during the sweating. EDA reflects the activity of the sympathetic axis of the autonomic nervous system. EDA is associated with the eccrine sweat gland at the palmar and plamar surface. This study was aimed to characterize the relationship between EDA and auditory stimulus intensities. Acoustic stimulus used in this study were 500 Hz, 1 kHz, 2 kHz of narrow band noise, which were representative of speech frequencies in audible range. Stimulus intensity between 90 and 30 dB in 10 dB within dynamic range. After deriving the minimum stimulus intensity(threshold of skin potential) which elicited skin potential, and then the latency and amplitude were derived from waveform of skin potential, each latency and amplitude were compared to stimulus intensity. The waveform of skin potential were recorded stably, and the threshold of skin potential appeared nearly the hearing threshold level of the participant. The latency was decreased and the amplitude was increased according to the increase of the stimulus intensity. These results suggest that auditory evoked skin potential can be applicable to auditory assessment and audiological diagnosis tool.

편측 인공와우 이식자의 보청기 사용

허승덕,김리석,정동근,최아현,고도홍,김현기,Heo, Seung-Deok,Kim, Lee-Suk,Jung, Dong-Keun,Choi, Ah-Hyun,Ko, Do-Heung,Kim, Hyun-Gi 한국음성학회 2005 음성과학 Vol.12 No.4

The cochlear implantation(CI) as an useful tool for aural rehabilitation in bilateral severe to profound hearing impairment. However, CI prefer to usually one ear in spite of bilateral hearing impaired. because of the various characteristics of hearing loss, the hearing conservation for the future possibility, and socioeconomic condition of hearing impaired person and their families. The unilateral CI has limitations such as a directional loss, a difficult speech understanding in noise and a neural plasticity. These limitations will be overcome by hearing aid(HA) which is familiar with hearing impairer. but HA fitting for bimodal-binaural hearing are difficult because the difference output characteristic of HA and CI. This study will be confirm realities of use of HA in unilateral cochlear implantee. For this goal, 25(m:f=10:15) child participated who are used to HA for 1 to 17 months. We had telephone interviews with their mother about use of HA, change of auditory performance and own voice. As the results, hearing threshold levels of unimplanted ear, the use of a appropriate HA, implanted and aided hearing threshold level(HTL) are must be considered for successful biomodal-binaural hearing. Especially, implanted and aided HTL should be very useful parameter for a prediction of HA effect and a criterion of selection for bilateral cochlear implantation.

이명이 없는 정상인의 이명 설문 결과

허승덕,문윤국,이강현 한국언어치료학회 2015 한국언어치료학회 학술발표대회 논문집 Vol.2015 No.12

전정구형낭 청력에 관한 연구

허승덕 한국음성학회 2012 말소리와 음성과학 Vol.4 No.3

The aims of this study are to consider auditory physiological characteristics and to confirm audiological evaluation and interpretation in regards to cases of sensorineural hearing loss that observe an abnormal AB gap. Vestibulosaccular hearing occurs when there is an abnormally large air-bone gap (AB gap) in sensorineural hearing loss, also known as pure cochlear conductive hearing loss. Generally, an AB gap is caused by damage to the external and/or middle ear. In conductive hearing loss, loss of air condition hearing occurs due to a loss of resonance in the outer ear and/or impedance mismatching in the middle ear. Most of these types of hearing loss can be treated medically and surgically. However, there is no medical treatment for an AB gap in sensorineural hearing loss and hearing loss can worsen gradually or suddenly. In addition, many studies have reported that head trauma makes hearing loss even more serious. Therefore, in order to differentiate between conductive hearing losses, it is important to check whether or not there is an enlarged vestibular aqueduct by means of temporal bone computerized tomography and/or magnetic resonance imaging.

와우 갑각 전기자극 뇌간유발반응용 원추형 전극의 개발

허승덕,정동근,강명구,김리석,고도흥 한국음성과학회 2003 음성과학 Vol.10 No.4

This paper introduces a new zinc coated copper wire electrode with coiled cone shape which has low surface resistance and tolerance to the motion artifact for promontory stimulation electrically auditory brainstem responses (PSEABR). Auditory brainstem responses (ABR) can be used to predict hearing threshold level with a great deal of accuracy particularly for a young child who cannot cooperate mechanically and some hearing impaired who are exaggerating a hearing loss for economic compensation. While severe profound sensorineural hearing losses may not be implemented by auditory potentials, PSEABR is proven as a useful tool even for some sensorineural related hearing impaired. It was shown that PSEABR gives the electrical stimuli to promontory of the cochlear instead of giving acoustic stimuli. For this reason, PSEABR can be used as an alternative for cochlear implantation, and can also be used as an optimal device selection and neural information for MAP. It was found that the role of electrode is very important in PSEABR. Even though this cone-shaped electrode was applied in animal experiments, waveforms are well produced by PSEABR. Thus, it was concluded that cone-shaped electrode turned out to be a useful preoperative audiological evaluation tool in deciding time for cochlear implantation surgery.

인공와우 이식자에서 자극 잡파를 이용한 고장 평가

허승덕,김상렬,안중기,정동근,강명구,Heo, Seung-Deok,Kim, Sang-Ryeol,Ahn, Joong-Ki,Jung, Dong-Keun,Kang, Myung-Koo 한국음성학회 2007 음성과학 Vol.14 No.2

The aim of this study is to analyze the correlation between current intensity and amplitude of stimulus artifact on the cochlear implantee, and to find out basic information to check the device failure. Subjects were a prelingual child and 3 postlingual adults with more than severe hearing losses. The charge-balanced biphasic pulses were presented at stimulus rates of 11 pulses per second, each pulse width of $25{\mu}s$ with monopolar mode(MP1+2). Current intensities were delivered at 27.5, 33.7, 41.3, 50.5, 61.9, $75.8{\mu}A$. Stimulus artifacts were recorded by evoked potential system. This procedure was performed just before the initial stimulation, and then, the amplitude of stimulus artifacts were compared with each current intensity. The amplitude of stimulus artifacts was increased significantly according to the current intensity (p<0.01). The results suggest that the change of the amplitude of stimulus artifact can be used as a good cue to check the device failure in the cochlear implantee.