측두골에 발생한 콜레스테롤 육아종의 임상적 양상

Cholesterol granuloma is not a clinically or pathologically independent entity. It may develop in any portion of the pneumatic system of the temporal bone and can be associated with a variety of middle ear disorders. Three factors are considered to play an important role in its development；1) interference with drainage 2) hemorrhage and 3) obstruction of ventilation. We reviewed 20 cases of cholesterol granuloma in the temporal bone by analysing findings of myringoscopy, temporal bone CT and/or MRI and operation, and concluded that cholesterol granuloma appeared clinically in three forms；1) in association with chronic otitis media, especially cholesteatoma 2) idiopathic blue eardrum 3) localized lesion in the middle ear, mastoid antrum, external auditory canal and petrous apex

일측성 전정기능전소실 환자에서의 회전반응검사

BACKGROUND: In general, it is well known that dizzy patients show a remarkable ability to compensate for the loss of peripheral vestubular function. When the patient had decreased response to caloric stimulation and showed no symptoms of vestibular dysfunction, we thought that was a compensated state of unilateral peripheral vestibular loss. OBJECTIVES: The purpose of this study is to provide the basic data for analysis of findings of further rotatory chair test through analyzing the results of rotation test of unilateral peripheral vestibular loss patients. MATERIALS AND METHODS: We analysed the findings of rotatory chair test and clinical manifestations of 24 cases of unilateral vestublar loss which didn't show any symptoms of vestibular dysfunction and they were confirmed by bithermal caloric test and Kobrak's ice water test. RESULTS: We could find that phase lead, low gain and asymmetry could persist despite of chronic compensated state and these findings were relatively common in patients with nonspecific vestibular symptoms. CONCLUSION: Abnornal phase lead and decreased gain were observed in the compensated unilateral vestibular loss patients who showed nonspecific symptoms including oscillopsia, vague unsteadiness. We thought that their compensation was not completely perfect and SHA test was a good tool which detect the minor degree of vestibular dysfunction. We have to consider the past history and nonspecific symptoms of patients through precise history taking. Frequency of SHA test is slower than that of normal human movement and this status is not a real physiologic condition, so it would be advisable to consider the results of other vestibular function tests for precise evaluation the degree of compensation, and the serial check is also recommended

소아 진주종 환자의 측두골 함기도에 대한 연구

BACKGROUND AND OBJECTIVES: Cholesteatoma occuring in childhood is often said to be more aggresive than that in adulthood, since cholesteatoma in children has a larger mastoid and earlier and more frequent recurrence as well as shorter disease history. In this sense, the pathogenesis of child cholesteatoma can be suspected to be different from that of adult cholesteatoma. The aim of this study is to show that cholesteatoma in children has more pneumatized mastoids than cholesteatoma in adults, and to find out the pathogenesis of child cholesteatoma which is deemed different from that of the adult. MATERIALS AND METHODS: In the present study, 20 child cholesteatomas and 20 adults cholesteatomas were used as subjects. We measured the size of mastoid air cells both in children and adult cholesteatoma by using a new analytical program for the temporal bone CT films. The size of the mastoid air cells was determined by the area of the plane showing a lateral semicircular canal on the temporal bone CT. The percent suppression in the area of the diseased side relative to that of the healthy side was calculated. RESULTS: The percent suppression was 10.5% in child cholesteatoma and 29.3% in adult cholesteatoma (P<0.05). CONCLUSION: We found that pneumatization of the mastoid air cells in children cholesteatoma was less suppressed than that in adult cholesteatoma

상악동 거상술 시 Waters' Projection의 유용성에 대한 임상적 연구

Purpose: Maxillary sinus elevation has been widely used to enable insertion of endosseous implants in severely resorbed maxilla. Maxillary sinusitis after this procedure was considered to be the major drawback, therefore, preoperative evaluation of paranasal sinus is considered to be important. In order to evaluate the condition of the sinus, we used Waters' projection. In this study, asymptomatic patients were evaluated by Waters' view, and compared to timing to assess the sinus cavity. Methods: The retrospective study was based on 14 patients who were performed sinus elevation surgery in Seoul National University Dental Hospital. These patients did not show any signs of maxillary sinusitis. These patients were taken Waters' view at preoperative, postoperative 1 day, 3 months, 6 months. In Waters' view, presence of air fluid level, radiopacity of sinus wall, or radiopacity of entire maxillary sinus were evaluated. The density, and sinus dimension changes were assessed using Adobe Photoshop CS5? (Adobe Systems Inc., San Jose, CA, USA). Results: Findings of Waters views in patients with clear maxillary sinus at preoperative time were followed by elevated sinus floor with transplanted bone, mucosal swelling, and air fluid level. At postoperative 3 months, and 6 months, the radiographic findings were similar to preoperative state. By contrast, patients with preoperative mucosal swelling, or haziness in sinus cavity showed radiopacity entire sinus in Waters' view. In cases of the patients who were treated with simultaneous treatment to mucosal swelling, good status of sinus cavity were found. Conclusion: Although Waters' projections provide the limited information, and is less sensitive method compared with computed tomography, it is simple, easy, and economical method to assess of maxillary sinus. We suggest using Waters' view as radiographic routine tool for evaluation of sinus condition, especially in the sinus elevation surgery

치과위생사의 직무스트레스, 자아존중감과 직무만족의 관련성 연구

본 연구는 치과위생사의 직무스트레스, 자아존중감과 직무만족의 관련성을 규명하기 위해 시도된 상관관계 연구이다. 치과위생사를 대상으로 인터넷 설문지를 이용하여 2015년 11월 24일부터 11월 30일까지 총 180부의 자료를 수집하였고 응답에 무성의한 2부를 제외하고 178부의 설문을 IBM SPSS version 19.0으로 분석하였다. 분석방법은 빈도분석, 기술통계분석, Independent t-test, One-way Anova, Scheffe test, Pearson's correlation coefficient, Multiple regression analysis 사용하였다. 연구결과는 다음과 같다. 첫째 , 일반적 특성에 따른 직무만족의 차이는 연령, 학력, 결혼상태, 근무경력, 직장분류, 취업형태, 월수입에서 통계적으로 유의한 차이가 나타났다. 사후검정 결과 연령은 30세 이상 , 학력은 대학원 졸업이상, 결혼상태는 기혼, 근무경력은 10년이상, 직장분류는 교육기관과 공공기관, 취업형태는 프리랜서, 월수입은 251만원 이상에서 직무만족 정도가 높은 것으로 나타났다. 둘째, 치과위생사의 직무스트레스, 자아존중감, 직무만족 간의 상관관계를 살펴 본 결과 직무스트레스, 자아존중감이 통계적으로 유의한 상관관계가 나타났다. 직무스트레스는 치과위생사의 직무만족과 통계적으로 유의한 음의 상관관계를 보여 직무스트레스가 높을수록 직무만족이 감소하는 것으로 확인되었다. 자아존중감은 치과위생사의 직무만족과 통계적으로 유의한 양의 상관관계를 보여 자아존중감이 높을수록 직무만족이 향상되는 것으로 확인되었다. 셋째, 치과위생사의 직무만족에 유의한 영향요인을 파악하기 위해 2단계 위계적 다중회귀분석을 실시한 결과 직무스트레스, 자아존중감 모두 유의한 영향요인으로 나타났으며, 그 외 일반적 특성에는 학력, 직장분류 (1차 의료기관) 유의한 영향요인으로 나타났다. 이 중 직무만족에 가장 많은 기여를 하는 예측변수는 직무스트레스였으며, 그 다음으로는 학력, 직장분류 (1차 의료기관), 자아존중감 순으로 나타났다. 결론적으로 본 연구는 치과위생사의 직무만족 요인으로 직무스트레스와 자아존중감의 역할을 실증적으로 확인하였다는 점에서 의의를 찾을 수 있다. 따라서 치과위생사의 직무만족을 향상시키기 위한 중재 방안 프로그램 개발에 기초자료를 제공하고자 한다.Ⅰ. 서 론--1 1. 연구의 필요성 -1 2. 연구의 목적 -3 3. 용어의 정의 -3 Ⅱ. 연구방법 -5 1. 연구설계 -5 2. 연구대상자 및 표본 -6 3. 자료수집방법 및 절차 -6 4. 연구도구 -7 5. 분석방법 -9 Ⅲ. 연구결과 -10 1. 대상자의 일반적 특성-10 2. 직무스트레스, 자아존중감, 직무만족 기술통계-12 3. 일반적 특성에 따른 직무만족 차이 검정-13 4. 직무스트레스,자아존중감과 직무만족의 상관성 -16 5. 직무스트레스,자아존중감과 직무만족의 관련성 -17 Ⅳ. 고찰 -22 Ⅴ. 결론 -26 참고문헌 -27 부록 -30 영문초록 -42 표 차 례 표 1. 대상자의 일반적 특성 -11 표 2. 직무스트레스, 자아존중감, 직무만족 기술통계 - 12 표 3. 일반적 특성에 따른 직무만족 차이 검정-15 표 4. 직무스트레스, 자아존중감과 직무만족의 상관성 - 16 표 5. 직무스트레스, 자아존중감과 직무만족의 관련성 - 21 그 림 차 례 그림 1. 잔차의 정규분포- 18 그림 2. 잔차의 정규확률 - 18 그림 3. 잔차의 등분산성 - 19 부 록 차 례 부록 1. 피험자 설명문 및 동의서- 30 부록 2. 설문조사도구 - 31 부록 3. 기관연구윤리심의위원회(IRB) 승인서-37 부록 4. 도구사용 승인 - 39Maste

압전-FET 결합 기계-전기 에너지 변환 및 이를 응용한 수중 음향센서 연구

DoctorIn contrast to the induced charge or voltage in conventional piezoelectric sensors, changes in the bound surface charge density and the corresponding changes in the electric field from a piezoelectric body do not depend on the size of the piezoelectric material. In this thesis, we describe a new transduction mechanism, the piezoelectric gate on a field-effect transistor (PiGoFET), focusing on the applications in micro-hydrophones. In the PiGoFET transduction mechanism, a piezoelectric body is combined directly on the gate of a field-effect transistor (FET) to decouple the sensitivity from the dimensions of the piezoelectric body, enabling the miniaturization of hydrophones. We describe a theoretical model of the PiGoFET, which shows that high sensitivity can be achieved with a small hydrophone due to the dimensionless characteristics of the PiGoFET transduction mechanism. The operating principle of the PiGoFET was analyzed using the theoretical model, which was experimentally verified in macro-scale device to within 2 dB. Using the verified theoretical framework for the PiGoFET, a micro-machined PiGoFET (micro-PiGoFET) hydrophone was designed and fabricated via hybrid bonding integration in a CMOS-compatible manner. The hybrid bonding integration employs separate wafers for the piezoelectric MEMS and CMOS processes, which are combined via eutectic wafer bonding to complete the micro-PiGoFET device. The resulting micro-PiGoFET hydrophone was characterized as an underwater acoustic receiver for frequencies in the range 50−1000 Hz. The internal pre-stress and polarization of PZT in the micro-PiGoFET were exploited to improve the sensitivity and signal-to-noise ratio (SNR). The measured sensitivity −156 ± 1 dB (Ref. V/μPa) of the micro-PiGoFET hydrophone was comparable to that of commercial reference hydrophone (B&K 8103) coupled with a charge amplifier (B&K 2692), provided that the noise floor of those sensors are similar. These results demonstrate the potential for high-performance miniaturized hydrophone systems for wide-band and low-frequency applications, as well as system-on-chip functionality

The performance enhancement of the hydrophone based on the piezoelectric gate of field effect transistor for low frequency application

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