개 흉부 방사선 자료의 딥러닝 적용을 통한 심장 면적 자동 분석 방법 개발

학위논문 (석사) -- 서울대학교 대학원 : 보건대학원 보건학과, 2021. 2. 성주헌 .Introduction : Measurement of canine heart size in thoracic lateral radiograph is crucial in detecting heart enlargement caused by diverse cardiovascular diseases. The purpose of this study was 1) to develop deep learning (DL) model that segments heart and 4th thoracic vertebrae (T4) body, 2) develop new radiographic measurement using calculated 2 dimensional heart area and length of T4 body, and 3) calculate performance of our new measurement to detect heart enlargement using echocardiographic measurement as gold standard. Methods : Total 1,000 thoracic radiographic images of dog were collected from Seoul National University Veterinary Medicine Teaching Hospital from 2018. 01. 01 to 2020. 08. 31. Given ground truth mask, two Attention U-Nets for segmentation of heart and T4 body were trained using different hyperparameters. Among 1,000 images, model was trained with 800 images, validated with 100 images and tested with 100 images. Performance of DL model was assessed with dice score coefficient, precision and recall. New calculation method was developed to calculate heart volume and adjust by T4 body length, which was named vertebra-adjusted heart volume (VaHV). Correlation of VaHV of 100 test images and reported VHS (vertebral heart score) was assessed. With 188 images with concurrent echocardiographic examination, diagnostic performance of VaHV for detecting cardiomegaly was assessed by students t-test, receiver operating characteristic (ROC) curve and area under the curve (AUC). Results : The two trained DL model showed very good similarity with ground truth (dice score coefficient 0.956 for heart segmentation, 0.844 for T4 body segmentation). VaHV of 100 test images showed statistically significant correlation with VHS. VaHV showed better diagnostic performance in detecting left atrial enlargement and left ventricular enlargement than VHS. Conclusions : DL model can be used to segment heart and vertebrae in veterinary radiographic images. Our new radiographic measurement obtained from DL model can potentially be used to assess and monitor cardiomegaly in dogs.개의 심장질환 중 가장 높은 유병률을 나타내는 이첨판 폐쇄부전증을 포함하여 다양한 심장질환이 점진적인 심비대를 특징으로 하기에, 개의 흉부 방사선 영상에서 심장 크기를 측정하여 심비대를 진단하는 것은 심장질환을 조기에 발견하고 적절한 치료시기를 계획하는 데 있어 매우 중요한 부분을 차지한다. 현장에서 바로 잴 수 있는 지표로서 기존에는 vertebral heart score (VHS)가 널리 사용되고 있으나, 이는 1차원 길이의 합으로 이루어진 지표이기에 심비대를 진단하는 데 한계가 있을 수 있다. 본 연구의 목적은 개의 흉부 방사선 영상에서 심장 면적과 척추체 길이를 자동으로 산출하는 딥러닝 모델을 구축하고, 이를 이용하여 심장 용적을 추정할 수 있는 지표를 개발하는 것이었다. 본 연구는 서울대학교 수의과대학 동물병원 검진자료로부터 수집된 총 1,188 건의 자료를 바탕으로 수행되었다. 1,000건의 영상은 심장과 척추체의 면적을 자동으로 분할 (semantic segmentation) 해주는 딥러닝 모델을 훈련시키고 평가하기 위해 사용되었으며, 이를 이용하여 새로운 심장 용적 지표인 vertebra-adjusted heart volume (VaHV) 를 산출했다. 추가로 1달 미만 간격의 방사선 촬영 기록과 심장초음파 검진 기록을 가진 188건의 영상을 수집하여 훈련된 딥러닝 모델을 이용해 계산한 VaHV와 심장초음파 기록 (LA/Ao, LVIDDN) 을 비교하여 VaHV의 심비대 진단능을 평가하였다. 심장과 척추체의 면적 불균형을 보완하기 위해 서로 다른 hyperparameter를 가진 Improved Attention U-Net이 사용되었으며, 두 개의 신경망 모두 시험용 데이터셋에서 정답 면적과 높은 일치율 (dice score coefficient 0.956, 0.844) 를 보였으며, 신경망의 예측결과에서 계산된 VaHV는 기존에 기록된 VHS와 통계적으로 유의한 상관계수를 (r = 0.69, P 1.6, LVIDDN > 1.7) 에 대해 높은 예측력을 가짐을 확인하였으며 (AUC 0.818), 기존에 사용되던 VHS의 예측력 (AUC 0.805) 보다 우수한 성능을 보임을 확인하였다. 본 연구는 수의방사선에서 최초로 딥러닝을 이용한 의미론적 면적 분할 (semantic segmentation) 을 적용하여 수의 영상에서 기존보다 더 다양한 신경망 알고리즘이 활용될 수 있는 가능성을 보여주었다. 또한 심장의 2차원 면적이 심비대를 진단함에 있어 기존의 길이 기반 심장 크기 측정 지표를 보완할 수 있다는 가능성을 보여주었다.1. Introduction 6 2. Materials and Methods 8 2.1 Data Collection 8 2.2 Development of DL model 10 2.2.1 Introduction to Semantic Segmentation 10 2.2.2 Attention U-Net with Focal Tversky Loss, Surface Loss 11 2.2.2.1 Attention U-Net 11 2.2.2.2 Improved Attention U-Net with Focal Tversky Loss 12 2.2.2.3 Surface Loss 14 2.2.3 Image Preprocessing 15 2.2.4 Establishing Ground Truth 16 2.2.5 Training DL Model 16 2.2.5.1 DL Model for Heart Segmentation 18 2.2.5.2 DL Model for T4 Body Segmentation 19 2.3 Volumetric Measurement of Heart 20 2.3.1 Analysis of Binary Mask 20 2.3.2 Vertebra-adjusted Heart Volume (VaHV) 21 2.3.3 Calculation of VaHV from DL Model Prediction 22 2.4 Statistical Methods 23 2.4.1 Segmentation DL Model Performance 23 2.4.2 Correlation between VaHV and VHS 23 2.4.3 Evaluation of Cardiomegaly using Echocardiographic Measurement 23 3. Results 24 3.1 DL Model 24 3.1.1 Heart Segmentation 24 3.1.2 T4 Body Segmentation 26 3.2 Descriptive Statistics of VaHV 28 3.3 Correlation between VaHV and VHS 29 3.4 Diagnostic Performance of VaHV for Detecting Cardiomegaly 30 4. Discussion 33 5. Conclusion 34 6. References 35 초록 38Maste

Familial factors associated with long term hospitalization among mental disableds

학위논문 (석사)-- 서울대학교 보건대학원 : 보건학과(보건정책관리 전공), 2015. 8. 김창엽.탈원화는 거스를 수 없는 세계적 추세이나, 한국에서는 가족들의 수용화에 대한 높은 요구로 인한 정신장애인의 수용화 문제가 불거지고 있다. 인권적 측면을 포함하여, 장기간의 입원은 정신장애인의 재활에 악영향을 미치기 때문에, 탈원화를 위한 과정은 지속되어야 한다. 본 연구는 장기 입원에 관련된 보호자 측의 요인들을 탐색함으로써, 그들의 미충족 필요와 요구를 반영하는 정책을 수립하기 위해서 시행되었다. 이 연구에서는 8명의 장기입원 조현병 및 조현정동장애 환자의 보호자들을 대상으로 개별 심층 면담을 하였다. 본 연구는 Colaizzi의 현상학적 방법을 사용하여 분석되었는데, 204개의 의미 있는 진술들이 선택되어 156개의 형성 의미를 도출하였고, 17개의 소주제와 6개의 범주가 완성되었다. 결과는 가족들의 경험과 욕구를 드러내기 위하여 총체적으로 기술되었다. 우선, 보호자들은 반복되는 재발로 인하여 퇴원을 두려워하는데, 이는 정서적 고통과 재정 문제 등과 같은 수많은 부담을 견뎌왔기 때문이었다. 둘째, 보호자들은 다양한 전략으로 차별과 낙인, 그리고 오명에 대응해 왔는데, 한편으로는 직접 차별의 주체가 되기도 하였다. 개인적 차별의 하나로써 과보호적 태도는 치료 결과에 대한 매우 높은 기준을 갖도록 한다. 또한 보호자들은 병원이 다른 정신보건 기관들에 비해 상대적으로 안전하다고 믿고 있었다. 그러나 장기 입원에 만족하는 것은 아니며, 국가가 환자의 재활과 지역사회 복귀에 적극적인 역할을 하기를 바라고 있었다. 이러한 보호자들의 요구는 정신장애인의 자기결정권과는 상충되는데, 이는 한국의 중요한 문화적 배경을 구성하는 가족주의에서 기인하는 것으로 보인다. 탈원화는 병상수의 감축뿐만 아니라, 지역사회 정신보건 체계의 굳건한 수립을 통하여 가족들의 부담을 줄여야만 성공적으로 정착될 것이다.Although deinstitutionalization is global trend, institutionalization of mental disabled is pressing issue in Korea due to the family members high demand on institutionalization. As long-term psychiatric hospitalization is known to have harmful effects on rehabilitation of mental disabled, we have to continue the process of deinstitutionalization from the human rights perspectives. The purpose of this study was to explore the family factors associated with long-term hospitalization, so that we could develop the policy which reflects the family members unmet need and demand. In this study, eight family members of mentally ill patients in long-term psychiatric hospital due to schizophrenia or schizoaffective disorder were interviewed through the personal in-depth interview. This study was analyzed using Colaizzis method of phenomenology. Two-hundred and four significant statements were selected, and 156 formulated meaning were extracted from the statements, to be clustered into 17 themes. These themes were categorized to 6 theme clusters. Theses results were reported by holistic description that illustrates the families experiences and their desires. First of all, family members of the patients with mental disorders were afraid of the mentally ill patients discharge and consecutive repetitive relapse of acute psychotic symptom. Thats because they have endured lots of familial burden on emotional distress, financial problems and so on. Second, they have dealt with recognized discrimination, labelling, and stigma in various ways, while they have played a role as actors of discrimination. In over-protectional attitude, which is one of personal discrimination, they could be reassured only to very high standard of treatment outcome. Third, they believed that mental hospitals are relatively safer than other kinds of institution. However, it does not mean that the family members has been satisfied with long term hospitalization being as they are. They really wanted the government to play an active role in the patients rehabilitation and their return to community. Their demands conflicted with the concept of human rights which let the mental disabled to self-regulate their life. The reason is likely to be familism which constructs Eastern Asian culture. Concurrent deinstitutionalization and decreased familial burden are successful if community mental health system would be well-developed.I. 서 론 ··········································································································· 1 1. 연구 배경 및 목적 ················································································ 1 2. 선행연구 고찰 ························································································ 8 3. 연구 방법 ······························································································ 17 II. 본 론 ······································································································· 34 1. 대주제 1: 정신장애인 보호자가 됨 ················································· 34 2. 대주제 2: 정신장애인 보호자로서의 부담 ······································ 37 3. 대주제 3: 차별, 낙인, 그리고 오명 (흉) ········································ 45 4. 대주제 4: 낫지 않는 병, 그리고 치료 ············································ 50 5. 대주제 5: 그나마 믿을 곳은 병원 ··················································· 61 6. 대주제 6: 보호자들의 요구와 필요 ················································· 70 III. 고 찰 ······································································································ 76 1. 본 연구에 대한 평가와 의의 ····························································· 76 2. 연구의 방법론적 제한점 ····································································· 79 Ⅳ. 결 론 ······································································································ 93 III. 참고문헌 ································································································ 94 VI. 부록 - 각 주제들을 형성한 의미들 ··············································· 100 VII. Abstract ···························································································· 110Maste

놀이를 강조한 비유 수업의 효과 : 중학교 3학년 물질 변화에서의 규칙성 단원을 중심으로

학위논문(석사)--서울대학교 대학원 :과학교육과 화학전공,2003.Maste