Computer-Aided Evaluation of Breast MRI for the Residual Tumor Extent and Response Monitoring in Breast Cancer Patients Receiving Neoadjuvant Chemotherapy

류채연,조나리야,김선미,장미정,박정선,백승연,문우경 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.1

Objective: To evaluate the accuracy of a computer-aided evaluation program (CAE) of breast MRI for the assessment of residual tumor extent and response monitoring in breast cancer patients receiving neoadjuvant chemotherapy. Materials and Methods: Fifty-seven patients with breast cancers who underwent neoadjuvant chemotherapy before surgery and dynamic contrast enhanced MRI before and after chemotherapy were included as part of this study. For the assessment of residual tumor extent after completion of chemotherapy, the mean tumor diameters measured by radiologists and CAE were compared to those on histopathology using a paired student t-test. Moreover, the agreement between unidimensional (1D) measurement by radiologist and histopathological size or 1D measurement by CAE and histopathological size was assessed using the Bland-Altman method. For chemotherapy monitoring, we evaluated tumor response through the change in the 1D diameter by a radiologist and CAE and three-dimensional (3D) volumetric change by CAE based on Response Evaluation Criteria in Solid Tumors (RECIST). Agreement between the 1D response by the radiologist versus the 1D response by CAE as well as by the 3D response by CAE were evaluated using weighted kappa (k) statistics. Results: For the assessment of residual tumor extent after chemotherapy, the mean tumor diameter measured by radiologists (2.0 ± 1.7 cm) was significantly smaller than the mean histological diameter (2.6 ± 2.3 cm) (p = 0.01), whereas, no significant difference was found between the CAE measurements (mean = 2.2 ± 2.0 cm) and histological diameter (p = 0.19). The mean difference between the 1D measurement by the radiologist and histopathology was 0.6 cm (95% confi dence interval: -3.0, 4.3), whereas the difference between CAE and histopathology was 0.4 cm (95% confi dence interval: -3.9, 4.7). For the monitoring of response to chemotherapy, the 1D measurement by the radiologist and CAE showed a fair agreement (k = 0.358), while the 1D measurement by the radiologist and 3D measurement by CAE showed poor agreement (k = 0.106). Conclusion: CAE for breast MRI is sufficiently accurate for the assessment of residual tumor extent in breast cancer patients receiving neoadjuvant chemotherapy. However, for the assessment of response to chemotherapy, the assessment by the radiologist and CAE showed a fair to poor agreement. Objective: To evaluate the accuracy of a computer-aided evaluation program (CAE) of breast MRI for the assessment of residual tumor extent and response monitoring in breast cancer patients receiving neoadjuvant chemotherapy. Materials and Methods: Fifty-seven patients with breast cancers who underwent neoadjuvant chemotherapy before surgery and dynamic contrast enhanced MRI before and after chemotherapy were included as part of this study. For the assessment of residual tumor extent after completion of chemotherapy, the mean tumor diameters measured by radiologists and CAE were compared to those on histopathology using a paired student t-test. Moreover, the agreement between unidimensional (1D) measurement by radiologist and histopathological size or 1D measurement by CAE and histopathological size was assessed using the Bland-Altman method. For chemotherapy monitoring, we evaluated tumor response through the change in the 1D diameter by a radiologist and CAE and three-dimensional (3D) volumetric change by CAE based on Response Evaluation Criteria in Solid Tumors (RECIST). Agreement between the 1D response by the radiologist versus the 1D response by CAE as well as by the 3D response by CAE were evaluated using weighted kappa (k) statistics. Results: For the assessment of residual tumor extent after chemotherapy, the mean tumor diameter measured by radiologists (2.0 ± 1.7 cm) was significantly smaller than the mean histological diameter (2.6 ± 2.3 cm) (p = 0.01), whereas, no significant difference was found between the CAE measurements (mean = 2.2 ± 2.0 cm) and histological diameter (p = 0.19). The mean difference between the 1D measurement by the radiologist and histopathology was 0.6 cm (95% confi dence interval: -3.0, 4.3), whereas the difference between CAE and histopathology was 0.4 cm (95% confi dence interval: -3.9, 4.7). For the monitoring of response to chemotherapy, the 1D measurement by the radiologist and CAE showed a fair agreement (k = 0.358), while the 1D measurement by the radiologist and 3D measurement by CAE showed poor agreement (k = 0.106). Conclusion: CAE for breast MRI is sufficiently accurate for the assessment of residual tumor extent in breast cancer patients receiving neoadjuvant chemotherapy. However, for the assessment of response to chemotherapy, the assessment by the radiologist and CAE showed a fair to poor agreement.

3차원 유방 초음파의 관찰자 일치도 및 진단적 정확성

류채연,김선미,장미정,김성원,강은영,박소연,문우경 대한초음파의학회 2011 ULTRASONOGRAPHY Vol.30 No.3

Purpose: We wanted to evaluate the interobserver variability and diagnostic performance of 3-dimensional (3D) breast ultrasound (US) as compared with that of 2-dimensional (2D) US. Materials and Methods: We included 150 patients who received US-guided core biopsy and 3D US between June 2009 and April 2010. Three breast imaging radiologists analyzed the 2D and 3D US images using the Breast Imaging Reporting and Data System (BI-RADS) lexicon. The intra-observer agreement and inter-observer agreement were calculated. The sensitivity and specificity of 2D and 3D US were evaluated. Results: The intra-observer agreement between 2D and 3D US was mostly slight or fair agreement. However, in terms of the final category, there was substantial agreement for all three radiologists. The inter-observer agreement of 3D US was similar to that of 2D US (moderate agreement for shape, orientation, circumscribed margin and boundary; fair agreement for indistinct margin, angular margin, microlobulated margin, echo pattern and final category). The sensitivity of 3D US for breast cancer was higher than that of 2D US for two radiologists (2D vs. 3D for reader 2: 55.8% vs. 61.5%, 2D vs. 3D for reader 3: 59.6% vs. 63.5%), and the specificity of 3D US was lower than that of 2D US for all the readers (2D vs. 3D for reader 1: 90.8% vs. 86.7%,2D vs. 3D for reader 2: 90.8% vs. 87.8%, 2D vs. 3D for reader 3: 94.9% vs. 90.8%),but the difference was not significant (p ≥ 0.05). Conclusion: The interobserver variability and diagnostic performance of 3D breast US were similar to those of 2D US. 목적: 유방 병변에 대한 3차원 초음파의 관찰자 일치도와 진단적 정확성을 기존의 2차원 초음파와 비교해 보고자한다. 대상 및 방법: 2009년 6월부터 2010년 4월까지 초음파유도 하 조직 생검과 3차원 초음파를 모두 시행한 환자 중종괴성 병변을 가진 150명의 환자를 대상으로 하였다. 초음파 소견은 유방영상의 판독과 자료체계 (Breast Imaging Reporting and Data System: BI-RADS) 지침을 기준으로, 3명의 유방 영상 전문의가 분석하였다. 관찰자 내 일치도와 관찰자 간 일치도, 각 초음파 진단법의 민감도와 특이도를 측정하였다. 결과: 각 판독의별 2차원과 3차원 초음파 분석 소견은대부분 불량 또는 보통의 일치도(관찰자 내 일치도)를 보였으나, 최종 카테고리에서는 3명의 판독의 모두 우수한일치도를 보였다. 초음파 소견의 각 항목에 대한 판독의들간의 일치도 (관찰자 간 일치도)는 2차원 초음파와 3차원초음파에서 비슷한 정도를 보였다 (불분명한 변연, 각진변연, 미세소엽형 변연, 에코양상, 최종 카테고리에서는 2차원과 3차원 모두 보통의 일치도; 모양, 방향성, 국한성변연, 병변 가장자리에서는 모두 중증도 일치도). 민감도는 판독의 두 명에서 2차원 보다 3차원 초음파가 더 높았고 (판독의2: 55.8%와 61.5%, 판독의3: 59.6%와63.5%), 특이도는 모두 2차원이 3차원 보다 높았으나 (판독의1: 90.8%와 86.7%, 판독의2: 90.8%와 87.8%, 판독의3: 94.9%와 90.8%), 통계적인 유의성은 없었다 (p ≥0.05). 결론: 3차원 초음파 영상은 2차원 초음파 영상과 비슷한수준의 관찰자 간 일치도와 진단적 정확성을 보였다.

블록체인 내 암호화 정보의 개인정보 해당성 여부

류채연 한국정보법학회 2022 정보법학 Vol.26 No.2

Is the encrypted information on the blockchain personal information (identifiable information or pseudonymous information) or anonymous information? Given the premise that encryption is used as a means of de-identification, there is no question that it is difficult or difficult to identify information, but various views are possible on the result. From the perspective of a business that implements a blockchain-based service model, there is room for recognizing encrypted information as anonymous information and determining that it is not subject to protection under the Personal Information Protection Act. However, in view of the flow of technological development, perfect encryption cannot exist, and when performing forensic work using additional information, there is room for backtracking the original information before encryption. In other words, it cannot be regarded as anonymous information that cannot be re-identified. This paper intends to examine what encryption information on the block is, focusing on the recent blockchain-based distributed identity authentication service. And based on the results of the review, we would like to present an independent opinion that, among the encrypted information, the issuance of qualification verification information is not personal information under the Personal Information Protection Act, and the DID and public key are identifiable information and not pseudonymous information. In reality, while the flow of digital transformation is accelerating and new technologies such as block chain are developing, there is a gap with these technological developments in the discussions within the law, such as the Personal Information Protection Act. It is a situation where the problem must be solved in a form that seeks specific validity by the interpretation of academia or judges for each case. Although the technology-neutral viewpoint of the provisions of the law is valid, it is necessary to specify standards to avoid arbitrary judgment of judges in subordinate statutes or guidelines. Looking at the issues that need to be supplemented, ① whether public key encryption, a block chain technology, can be viewed as pseudonymous processing, or ② whether the process of decrypting encrypted information using an encryption key and re-identification through the combination of additional information of pseudonymous information is considered the same?, ③ It concludes with a discussion of the distinction between ‘other information’ when reviewing identifiable information and ‘additional information’ for re-identification potential when processing pseudonyms. Legal rights that can be linked to new technologies, such as the Personal Information Protection Act, need to be adjusted in accordance with the flow of technological development. By clarifying the relevant standards in the guidelines, it is reasonable to secure predictability for blockchain-based service providers and at the same time safely protect the personal information of the service users. 블록체인 위의 암호화 정보는 개인정보(식별가능정보 내지 가명정보)인가, 익명정보인가? 암호화가 비식별 조치의 수단으로 이용된다는 전제에 비춰보면 식별이 곤란하거나 쉽지 않은 정보라는 점에는 이론의 여지가 없을 것이나, 그 결과물에 대해서는 다양한 견해가 가능하다. 블록체인 기반 서비스 모델을 구현하는 사업자 입장에서는 암호화 정보를 익명정보로 인식하고, 개인정보보호법상 보호 대상이 되지 않는다고 판단할 여지가 있다. 하지만 기술발전 흐름에 비춰볼 때 완벽한 암호화란 존재할수 없으며, 암호화 정보는 부가적인 정보를 이용해 포렌식 작업을 수행시 암호화 이전의 원래 정보를 역으로 알아낼 여지가 있다. 즉, 재식별이 불가능한 익명정보로 볼수 없다. 본 논고는 최근 블록체인 기반의 분산신원인증 서비스를 중심으로, 블록 위 암호화정보가 무엇인지 살펴보고자 한다. 그리고 검토 결과를 토대로 암호화 정보 중 자격검증 발급정보는 개인정보보호법상의 개인정보가 아니고, DID와 공개키는 식별가능정보일 뿐 가명정보가 아니라는 독자적 견해를 제시하고자 한다. 현실에서는 디지털전환 흐름이 가속화되고 블록체인 등 신기술이 발전하는데 반해, 개인정보보호법 등의 법학 내 논의는 이러한 기술적 발전과 간극이 있는 상태다. 각 사안별로 학계 내지법관의 해석에 의해 구체적 타당성을 꾀하는 형태로 문제를 해결해야 하는 상황이다. 법률 조항의 기술중립적 관점은 타당하나, 하위 법령 내지 지침에는 법관의 자의적인 판단을 지양할 수 있는 기준이 명시될 필요가 있다. 보완될 필요성 있는 쟁점을 살펴보면 ① 블록체인 기술인 공개키 암호화를 가명처리로 볼 수 있는지, 또는 ② 암호화 정보를 암호키를 통해 복호화하는 과정과 가명정보의 추가정보 결합을 통한 재식별 작업을 같게 볼 것인지, ③ 식별가능정보 검토시 ‘다른 정보’와 가명처리시 재식별가능성에 대한 ‘추가정보’의 구별의 논의로 귀결된다. 지침 내 관련 기준을 명확히 함으로써, 블록체인 기반 서비스 사업자에게 예측가능성을 확보해주고 동시에 해당 서비스 이용자의 개인정보는 안전하게 보호함이 타당하다.

영화 ‘버킷리스트’에 나타난 노년기의 성찰과 학습 사례연구

류채연(Ryu Chae Yeon),최운실(Choi Un Shil) 학습자중심교과교육학회 2019 학습자중심교과교육연구 Vol.19 No.18

본 연구목적은 노년기의 삶과 죽음의 특징들을 영화 <버킷리스트>에 나타난 성찰과 학습에 관해 탐구하는 데 있다. 연구의 목적은 영화 <버킷리스트>의 두 주인공을 통해 본 버킷리스트의 의미와 노년의 성찰은 평생교육적으로 어떤 의미가 있는 가를 살펴보기 위해 성찰학습이론과 내용분석의 연구방법을 활용하였다. 연구 결과, 우리가 꼭 해야 할 일이나 하고 싶은 일의 목록을 적은 버킷리스트는 그동안 삶의 가치를 어디에 두었는가를 생각하게 하며 행동으로 이끄는 도구로 나타났다. 따라서 이들에게 버킷리스트는 삶의 희망이며 삶의 가치를 찾아 나서는 여행이 되었다. 자신에게 집중하며 긍정적인 마음과 자신을 성찰하게 된 시간을 가지게 되었고 또 그 시간만큼 성장하게 된다. 또한, 노년기의 자신의 삶을 성찰하고 반추하는 일은 자신의 삶을 긍정적으로 수용하고 인간관계를 성장시키는 요인이며 지혜로운 ‘나이듦’에 대한 인식이라고 할 것이다. The purpose of this study is to explore the characteristics of life and death of old age in reflection and learning in the movie ‘Bucket List’. The purpose of this study was to use the study method of reflection learning theory and content analysis to examine the meaning of bucket list and the meaning of old age reflection in the two main characters of the movie ‘Bucket List’. Research has shown that bucket lists, which list the things we must do or want to do, are tools that lead us to think about where we put our values in life. Thus, for them, the bucket list is a hope of life and a journey to find out he value of life. You have the time to focus on yourself, reflect on yourself and reflect on yourself, and grow as much as that time. In addition, reflecting on and reflecting on your own life in old age is a factor in positively accepting your life and growing relationships, and a wise perception of aging.

과학연구용 로케트 개발을 위한 필수기술 연구 (Ⅰ) ( Research on Essential Technologies for the Development of Sounding Rocket (Ⅰ) )

류장수,채연석,김재수,이영무,조광래,박정주,오범석,오승협,승성표,이재득,정의승 대한전자공학회 1989 특정연구 결과 발표회 논문집 Vol.- No.-

과학연구용 로케트 개발을 위한 필수기술 연구 ( 1 ) ( Research on Essential Technologies for the Development of Sounding Rocket ( 1 ) )

류장수,채연석,김재수,이영무,조광래,박정주,오범석,오승협,승성표,이재득,정의승 한국통신학회 1989 한국통신학회 학술대회논문집 Vol.1 No.1

영상의학과 전공의들의 선별유방촬영 판독 성취도

이은혜,류채연 대한영상의학회 2013 대한영상의학회지 Vol.68 No.4

Purpose: To evaluate radiology residents’ performance in screening mammography interpretation and to analyze the factors affecting performance. Materials and Methods: We enrolled 203 residents from 21 institutions and performed mammography interpretation tests. Between the trainee and non-trainee groups, we compared the interpretation score, recall rate, sensitivity, positive predictive value (PPV) and false-positive rate (FPR). We estimated the training effect using the score differences between trainee and non-trainee groups. We analyzed the factors affecting performance between training-effective and non-effective groups. Results: Trainees were superior to non-trainees regarding interpretation score (43.1 vs. 37.1), recall rate (11.0 vs. 15.5%), sensitivity (83.6 vs. 72.0%), PPV (53.0 vs. 32.4%) and FPR (13.5 vs. 25.5). The longer the training period, the better were the interpretation score, recall rate, sensitivity, PPV and FPR (rho = 0.486, -0.375, 0.343, 0.504, -0.446, respectively). The training affected an increase by an average of 6 points; however, 31.6% of institutions showed no effect. A difference was noted in the volume of mammography interpretation during a month (594.0 vs. 476.9) and dedication of breast staff (61.5 vs. 0%) between training-effective and non-effective groups. Conclusion: Trainees showed better performance in mammography interpretation compared to non-trainees. Moreover, performance was correlated with the training period. The factors affecting performance were the volume of mammography interpretation and the dedication of the breast staff. 목적: 영상의학과 전공의들의 선별유방촬영 판독 성취도를 평가하고 수련효과 관련인자를 분석하였다. 대상과 방법: 21개 영상의학과 수련기관의 전공의 203명을 대상으로 선별유방촬영 판독평가와 설문조사를 시행하였다. 수련군과 비수련군에서 판독점수, 소환율, 민감도, 양성예측도, 위양성률 등 판독 성취도를 비교하였고, 각 기관의 수련군 전공의들과 비수련군 전공의들 간의 평균 판독점수 차로 수련효과를 측정하였다. 수련기관을 수련 효과군과 비효과군으로 나누어 판독 성취도 관련인자를 분석하였다. 결과: 수련군이 비수련군보다 판독점수(43.1 vs. 37.1), 소환율(11.0 vs. 15.5%), 민감도(83.6 vs. 72.0%), 양성예측도(53.0 vs. 32.4%), 위양성률(13.5 vs. 25.5)이 높았다. 수련기간이 길수록 판독점수, 민감도, 양성예측도는 올라가고(rho = 0.486, 0.343, 0.504), 소환율과 위양성률은 감소하였다(rho = -0.375, -0.446). 수련효과는 평균 6점이었으나 31.6%의 기관은 수련효과가 없었다. 수련기관 중 수련 효과군과 비효과군은 전공의의 한 달 간 유방촬영 판독량(594.0 vs. 476.9)과 유방영상 담당교수의 전임여부(61.5 vs. 0%)에 차이가 있었다. 결론: 수련군이 비수련군보다 선별유방촬영 판독 성취도가 높았으며, 수련기간에 비례하여 판독 성취도가 향상되었다. 수련효과 관련인자는 유방촬영 판독량과 유방영상 담당교수의 전임여부였다.

높이가 제한된 의사결정나무의 성능 향상을 위한 유전프로그래밍 기반 특징 추출 방법론

최성근,백채연,류슬기,전성범 대한산업공학회 2023 대한산업공학회 추계학술대회논문집 Vol.2023 No.11

Usefulness of Ultrasound and Ultrasound-guided Fine-Needle Aspiration Biopsy for Axillary Staging in Breast Cancer: Analysis of 327 patients at a single institution

장미정,김선미,류채연,문우경,조나리야,강은영,김성원,박소연,김지현,김유정 대한초음파의학회 2010 ULTRASONOGRAPHY Vol.29 No.4

Purpose: To evaluate the accuracy of ultrasound (US) and US-guided fine needle aspiration biopsy (FNAB) for the diagnosis of metastasis in the axillary lymph node (LN) of patients with breast cancer. Materials and Methods: A retrospective review of the data was performed on 327breast cancer patients that underwent axillary US from Jun 2006 to July 2008. USguided FNAB was performed when a LN indicated suspicious findings. Results of FNAB were compared with those of subsequent surgery. Results: Of the 327 patients, 111 showed suspicious findings on US and underwent FNAB. Among the 111 cases, 73 (66%) were positive for cancer, while 38 (34%)were negative results. A Total of 254 patients who had normal findings on US (n=216) and negative results on FNAB (n=38) underwent SNB, of which 56 (22%)were proven to have metastasis. Sensitivity and specificity of US were 61.9% and 81.8%, respectively, with a positive predictive value (PPV) of 65.8% and negative predictive value (NPV) of 79.2%. Sensitivity and specificity of US-guided FNAB were 86.9% and 100%, respectively, with a PPV of 100% and a NPV of 71.7%. Conclusion: US and US-guided FNAB performed for axillary staging are useful methods with a high specificity and positive predictive value in invasive breast cancer patients.

JPEG2000을 이용한 유방촬영술 팬텀 영상의 압축 비율별 평가

정영주,양상규,김수완,류채연,이병희,김기환 대한영상의학회 2007 대한영상의학회지 Vol.56 No.6

Purpose: To determine the usefulness of compression standard JPEG2000 for compression of mammographic images. Materials and Methods: Image of a mammographic phantom was compressed using JPEG2000 at ratios of 10:1, 20:1, 30:1, 40:1, 50:1 and 60:1. The sizes of the images were compared, and scores were recorded by counting the numbers of fibers, groups of specks and masses seen in each phantom image. More than four fibers, three groups of specks and three masses and a total score of 10 were considered acceptable. Results: The size of a DICOM image was 17,042 KB, a TIFF image was 8,324 KB, the original JPEG image was 1,506 KB and the most compressed image (50:1) above an acceptable total score of 10 was 43 KB. In each category, the compression image of fiber was acceptable up to compression ratio of 50:1 (score of 5), groups of specks was acceptable up to 60:1 (score of 3) and mass was acceptable up to 50:1 (score of 3.5). The total score, which was acquired by adding up the individual scores of all three categories, for a compression ratio of 50:1 was 12 and was acceptable, but the total score for 60:1 was 8 and was not acceptable. Conclusion: The compression standard JPEG2000 is an efficient means for compressing mammographic images at high ratios without compromising diagnostic value. 목적: 유방촬영술 영상의 압축에서 JPEG2000의 유용성을 알아보고자 하였다. 대상과 방법: JPEG2000압축 기법을 사용하여 유방촬영술 팬텀 영상을 10:1, 20:1, 30:1, 40:1, 50:1, 60:1까지 압축하였다. 유방촬영술 팬텀의 DICOM, TIFF, JPEG 원본 영상과 압축 영상을 포함한 총 9개의 영상을 4명의 판독의가 합의로 평가하였다. 영상의 용량을 비교하였고 팬텀영상에서 보이는 섬유, 작은 알갱이 집단들, 종괴의 개수를 세어 점수를 기록하였다. 섬유 4개 이상, 작은 알갱이 집단들 3개 이상, 종괴 3개 이상(총점 10점 이상)을 합격으로 간주하였다. 결과: DICOM 영상의 용량은 17,042KB, TIFF 영상은 8,324KB, JPEG 원본 영상은 1,506KB이었고 합격점 이상에서 가장 높은 압축비인 50:1에서의 영상의 용량은 43KB이었다. 분야별 점수에서 섬유는 50:1의 압축비까지 5점으로 합격이었고, 작은 알갱이 집단들은 60:1의 압축비까지 3점으로 합격이었으며, 종괴는 50:1의 압축비까지 3.5점으로 합격이었다. 총점에서는 섬유, 작은 알갱이 집단들, 종괴 각각의 점수를 합치면 50:1의 압축비까지 12점으로 합격이었고 60:1의 압축비는 8점으로 불합격이었다. 결론: JPEG2000은 유방촬영술에서 비교적 영상의 손실 없이 높은 압축이 가능한 효율적인 압축 기법이다.