• 대한전자공학회논문지SP
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• 제38권4호
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• pp.1-1
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• 2001

본 논문에서는 웨이블릿 변환을 멀티스케일 매치 필터의 관점에서 해석하고, 이를 위하여 마르코프 랜덤 필드에 묻혀있는 가우시안 형태의 작은 물체를 검출하는 이론적 근거를 제시하며, 이의 응용으로 맘모그램에 존재하는 마이크로캘시피케이션을 검출하는 알고리즘을 제안한다. 검출하고자 하는 물체가 가우시안 형태이고 그 스케일이 웨이블릿 변환에 의해 계산된 것과 일치하며, 그 주변의 잡영이 마르코프 프로세스이면, LoG(Laplacian of Gaussian) 웨이블릿은 멀티스케일 매치 필터로 작용하며, 적절한 디테일 이미지를 단순히 이진화함으로써 최적의 검출기를 구현할 수 있다. 그런데, 마이크로캘시피케이션은 정확한 가우시안 형태를 갖지 않고, 게다가 맘모그램의 배경이미지도 마르코프 프로세스라는 가정에서 벗어난다. 이러한 불일치를 해결하기 위하여, 본 논문에서는 멀티스케일 웨이블릿 계수에서 추출한 특징벡터를 Hotelling observer에 입력하여 처리함으로써 이를 보상하고자 하였다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 춘계학술대회
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• pp.142-145
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• 1995

스크린-필름 X선 유방조영술(Screen-film X-ray mammography)은 유방암 진단을 위한 기준이 되는 방법으로 독보적인 위치를 차지하고 있다. 그러나 현재 사용되는 스크린-필름 방식 유방조영술은 여러 가지 한계점들이 인식되어 왔으며, 만약 유방 X선 사진(mammogram)이 디지탈 형식으로 곧 바로 얻어진다면 영상의 질(image quality)과 방사선량의 감소 가능성 관점에서 향상될 수 있다는 증거가 있다. 본 논문에서는, 디지탈 유방조영술에 대한 논리적 근거가 제시되고, 스크린 대용으로 개발되고 있는 X-선 검출기들과 이들을 사용한 여러가지 디지탈 유방조영술 시스템들을 분석 전망한다. 디지털 유방조영술을 실용화하기 위해 해결되어야 할 문제점들이 논의된다.

• 한국컴퓨터정보학회논문지
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• 제21권1호
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• pp.9-16
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• 2016

In this paper, we present a performance evaluation agent based on fuzzy cluster analysis and validity measures. The proposed agent is consists of three modules, fuzzy cluster analyzer, performance evaluation measures, and feature ranking algorithm for feature selection step in CAD system. Feature selection is an important step commonly used to create more accurate system to help human experts. Through this agent, we get the feature ranking on the dataset of mass and calcification lesions extracted from the public real world mammogram database DDSM. Also we design a CAD system incorporating the agent and apply five different feature combinations to the system. Experimental results proposed approach has higher classification accuracy and shows the feasibility as a diagnosis supporting tool.

• Journal of the Optical Society of Korea
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• 제9권4호
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• pp.157-161
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• 2005

Medical infrared imaging is obtained by measuring the self-emitted infrared radiance from the human body. Infrared emission is related to surface temperature and temperature is one of the most important physiological parameters related to health. Though recent applications such as security identification and oriental medicine have provided new fields of biomedical applications, infrared thermography has had ups and downs in its usages in cancer detection. Some of the main difficulties include finding proper applications and efficient diagnostic algorithms. In this study, infrared thermal imaging was used to detect regional metastasis of breast cancer. Our measurements were done for 110 women. From 63 individuals of a Healthy Group and a Benign Breast Disease Group, we developed algorithms for differentiating malignant regional metastasis based on temperature difference and asymmetry of temperature distribution. Testing with 47 cancer patients, we achieved a positive predictive value of $87.5\%$ and a negative predictive value of $95.6\%$. The results were better than for mammogram examination. A proper analysis of infrared imaging proved to be a highly informative and sensitive method for differentiating regional cancer metastasis from normal regions.

• 대한핵의학회지
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• 제33권5호
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• pp.452-460
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• 1999

목적: Tc-99m tetrofosmin을 이용한 유방 신티그라피의 진단적 유용성을 알아보고자 하였다. 대상 및 방법: 유방종괴를 주소로 내원하여 단순 유방조영술, 초음파 및 Tc-99m tetrofosmin 유방 신티그라피를 시행한 61명의 환자를 대상으로 하였다. Tc-99m tetrofosmin 주사 5분 후에 측면상 및 전면상을 얻었고 1시간 후에 측면상을 다시 얻었다. 영상판독은 양성, 양성가능, 음성가능, 음성으로 나누었다. 종양/배후방사능비를 조기 및 지연 측면영상에서 각각 측정하여 비교하였다. 단순 유방조청상의 판독은 5 category로 나누었다. 확진은 수술(58/61) 또는 세침흡인(3/61)으로 이루어졌다. 61명 중 44명이 유방암, 17명이 양성 유방 질환으로 확진되었다. 유방암 종괴 44예의 크기는 $1{\sim}8cm$(평균 $2.51{\pm}1.30cm$)였고 양성 종괴 17예 중 16예의 크기는 $0.96{\sim}6 cm$(평균 $2.50{\pm}1.35 cm$)으로서 차이가 없었다. 결과: 단순 유방조영술의 민감도는 88.6%, 특이도는 58.8%, 양성 예측률은 84.7%, 음성 예측률은 66.7%였다. Tc-99m tetrofosmin 유방 신티그라피의 민감도는 90.9%, 특이도는 88.2%, 양성 예측률은 94.9%, 음성 예측률은 78.9%였다. 단순 유방조영상에서 악성도 미정으로 판독된 25명의 환자 중 23명은 유방 신티그라피에 의해 정확하게 진단할 수 있었다. 종양/배후방사능비는 5분 및 1시간 영상에서 각각 $3.78{\pm}2.21$, $3.25{\pm}1.80$이었고 통계적으로 유의하게 감소하였다(p<0.001). 결론: Tc-99m tetrofosmin 유방신티그라피는 유방암 진단에 유용한 검사이고 특히 단순 유방조영상에서 악성도 미정으로 판독된 환자에서 특히 유용할 것으로 사료된다.

• 대한영상의학회지
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• 제83권5호
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• pp.1090-1103
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• 2022

목적 본 연구는 미세석회화가 의심되는 유방에서 정위적 조직검사에 앞서서 시행하는 디지털 유방단층영상합성법(digital breast tomosynthesis with the two-dimensional synthesized mammogram; 이하 DBT with 2DSM)과 전면디지털유방촬영술(full-field digital mammography; 이하 FFDM)의 진단능을 비교 평가하고 영상의 진단적 명확도를 평가하기 위해서 시행하였다 대상과 방법 2015년 1월에서 2020년 1월까지 후향적 연구로서 189명의 환자 중 정위적 조직검사를 통한 조직병리검사상 미세석회화 병변이 확인된 환자를 중 DBT with 2DSM나 FFDM을 시행한 환자군에서 시행되었다. 두 명의 영상의학과 의사가 눈가림 상태로, Breast Imaging Reporting and Data System (BI-RADS) 분류에 따른 미세석회화의 평가 및 본 연구에서 별도로 1-5점 척도를 통해 정의한 진단적 명확도에 대한 평가를 시행하였다. 결과 전반적인 검사자간 일치도는 우수한 것으로 확인되었다. 맥네머 검정에서 악성가능성이 높은 미세석회화(4B, 4C, or 5)의 검출에 있어서는 두 진단방법 간에 통계적 유의성은 보이지 않았으나, 양성가능성이 높은 미세석회화(4A)의 진단에 있어서는 통계적 유의성을 보였다. DBT with 2DSM는 FFDM보다 더 높은 가시성을 보임이 확인되었고, 치밀유방에서도 FFDM보다 진단에 있어서 더 우수하였다. 결론 DBT with 2DSM는 FFDM과 비교하여 미세석회화 병변에 대해서 더 높은 전반적 진단적 정확도와 진단적 명확성을 제공하였다. DBT with 2DSM는 FFDM보다 양성 미세석회화 병변에서와 치밀유방에서 우수성을 보였다. 본 연구에서는 치밀 유방에서 미세석회화 병변에 대해서 정위적 생검을 시행할 때 유용한 진단 기구로서의 DBT with 2DSM의 역할을 확인할 수 있었다.

• 대한간호학회지
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• 제30권5호
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• pp.1265-1278
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• 2000

This study was carried out to assess the perception of decisional balance of Korean subjects about 4 health behaviors and to identify the influencing factor of decisional balance for exercise acquisition, smoking cessation, mammography screening and Kegel's exercise acquisition. All are representative health behaviors nurses can intervene in Korea based on the Transtheoretical model. Convenient samples of 2,484 subjects (191; exercise, 169; smoking cessation, 1903; mammography screening and 221; Kegel's exercise) were selected from cities and counties over 9 provinces throughout Korea, and the data was collected from January 1, 1999 to February 29, 2000. The research instrument were the Decisional Balance Measure for Exercise (Marcus & Owen., 1992), Smoking Cessation (Velicer et al., 1985), Mammography Screening (Rakowski et al.,1992) and Kegel Exercise (Lim, 1999) and Stage of Change Measure for Exercise (Marcus et al, 1992), Smoking Cessation (DiClemente et al., 1991), Mammography Screening (Rakowski et al.,1992) and Kegel's Exercise (Lim, 1999). The data was analyzed by the SAS Program. The results are as follows; 1. According to the stage of change measure, 2,484 subjects were distributed in each stage of change for four health behaviors: 1,233 subjects (49.8%), 745 subjects (30.2%), 113 subjects (4.7%), 156 subjects (6.5%), and 216 (8.7%) belonged to the pre- contemplation stage, contemplation stage, preparation stage, action stage and maintenance stage. They were all series of stages of change in their efforts to do health behavior. 2. Factor analysis identified 3 factors (1 of Pros, 2 of Cons) for the exercise, 4 factors for smoking cessation (2 of Pros, 2 of Cons), 2 factors (1 of Pros, 1 of Cons) for the mammogram screening and 2 factors (1 of Pros, 1 of Cons) for Kegel's exercise of decisional balance. 3. The analysis of variance and multiple comparison analysis showed that for all 4 samples, the Cons of changing the problem behaviors outweighed the Pros for subjects who were in the pre- contemplation stage, The opposite was true for subjects in action and maintenance stage. 4. Through the discriminant analysis, it was found that one factor of Pros for exercise, one factor of Cons for smoking cessation, 1 factor of Cons for mammogram screening and one factor of Cons for Kegel's exercise were the more influencing factors, than others in discriminating the stages of change. Results are consistent with the applications of the Transtheoretical model, which have been used to understand how people change health behaviors. This results provide some evidence that subject's report of his/her health behavior corresponds to beliefs about usefulness of related health behaviors. The results of this study have implications for patients' health education and health intervention strategies. The findings of this study give useful information for nursing educators for 4 health behaviors, especially the factors relating to decision making in the different stages of change.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1929-1934
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• 2015

Purpose: To determine the diagnostic yield of primary circulating tumor cells in women with suspicion of breast cancer, detected as a result of an abnormal mammography. Materials and Methods: Consecutive women presenting for breast biopsy as a result of a mammogram BiRADs of 3 or more, had an 8ml blood sample taken for primary circulating tumor cell (CTC) detection. Mononuclear cells were obtained using differential gel centrifugation and CTCs identified using standard immunocytochemistry using anti-mammoglobin. A test was determined to be positive if 1 CTC was detected. Results: A total of 144 women with a mean age of $54.7{\pm}15.6$ years participated, 78/144 (53.0%) had breast cancer on biopsy, 65/140 (46.3%) benign pathologies and 1(0.7%) non-Hogkins lymphoma. Increasing BiRADs scores were associated with increased cancer detection (p=0.004, RR 1.00, 4.24, 8.50). CTC mammoglobin positive had a sensitivity of 81.1% and specificity of 90.9%, with positive and negative predictive values of 90.9% and 81.1% respectively. Mammoglobin positive CTCs detected 87% of invasive cancers, while poorly differentiated cancers were negative for mammoglobin. Only 50% of in situ cancers and none of the intraductal cancers had CTCs detected. Menopausal status did not affect the diagnostic yield of the CTC test, which was higher in women with BiRADS 4 mammograms. There was a significant trend (p<0.0001 Chi squared for trends) in CTC detection frequency from intraductal, in situ and invasive (OR 1.00, 8.00, 472.00). Conclusions: The use of primary CTC detection in women suspected of breast cancer has potential uses, especially with invasive cancer, but it failed to detect intra-ductal cancer and 50% of in situ cancer. There was no difference in the diagnostic yield between pre and post menopausal women. To confirm its use in reducing biopsies in women with BIRADs 4a mammagrams and in the detection of interval invasive breast cancer, larger studies are needed.

• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2549-2554
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• 2016

Background: Early detection remains the cornerstone of breast cancer control in terms of outcome and survival. Thus far the only breast cancer screening method proven effective is mammography. The awareness of female health care workers (HCW) about breast cancer prevention is of vital importance, as their beliefs and behavior may have a major impact on other women. This study was designed to assess mammography screening uptake among female healthcare workers at primary healthcare centers, and to identify the primary motivators and barriers that affect uptake results. Materials and Methods: A cross sectional study design was used to assess mammography screening by 299 female healthcare workers who completed a self-administered questionnaire that assessed demographics, screening uptake, motivators and barriers. Results: The mean age was 46 years (within age of risk). The majority (95.1%) demonstrated adequate knowledge about breast cancer and mammography screening and 50% of the participants reported having at least one mammogram; however only 21% of them had regularly scheduled mammograms. The most frequent reported motivator was the perceived benefit that early detection of breast cancer is important for its management (89.6%), followed by the belief that mammography can detect breast cancer before its symptoms appear (84.4%). On the other hand, the most frequent barrier reported was being busy (46.7%), followed by the lack of perceived susceptibility (41.5%). Conclusions: Mammography screening was found to be sub-optimal in a population of HCW's with 50 % stating that they received a mammogram at least once, and a minority reported regular screening. There is a pressing need for educational programs aimed at removing the barriers that limit compliance with recommendations for mammography screening, and to emphasize the importance of early detection in breast cancer treatment. Ensuring the availability and accessibility of screening services, particularly for healthcare workers within their work settings are other important factors that would improve the acceptance and compliance for mammography screening programs.

• Journal of Multimedia Information System
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• 제3권3호
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• pp.97-102
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• 2016

Deep learning enables machines to have perception and can potentially outperform humans in the medical field. It can save a lot of time and reduce human error by detecting certain patterns from medical images without being trained. The main goal of this paper is to build the optimal model for breast mass classification by applying various methods that influence the performance of Convolutional Neural Network (CNN). Google's newly developed software library Tensorflow was used to build CNN and the mammogram dataset used in this study was obtained from 340 breast cancer cases. The best classification performance we achieved was an accuracy of 0.887, sensitivity of 0.903, and specificity of 0.869 for normal tissue versus malignant mass classification with augmented data, more convolutional filters, and ADAM optimizer. A limitation of this method, however, was that it only considered malignant masses which are relatively easier to classify than benign masses. Therefore, further studies are required in order to properly classify any given data for medical uses.