도플러 초음파 신호에서의 태아 심박 검출 개선

권자영(Ja Young Kwon),이유빈(Yu Bin Lee),조주현(Ju Hyun Cho),이유진(Yoo Jin Lee),최영득(Young Deuk Choi),남기창(Ki Chang Nam) 대한전자공학회 2012 전자공학회논문지 Vol.49 No.9

산전 및 분만 중 연속적인 태아감시는 임상의에게 태아의 안녕 평가하는데 필요하다. 또한 태아의 심장박동은 임신 중 태아의 건강을 평가하는 중요한 파라미터이다. 초음파 도플러는 태아 심박을 비관혈적으로 측정할 수 있는 방법으로 매우 유용하다. 그러나 현재 임상에서 널리 쓰이고 있음에도 불구하고, 태아 심박을 검출하는데 있어서 제한적인 정보만 제공할 뿐만 아니라 검출 오류에 대한 문제가 완전히 해결되지 못하고 있다. 본 연구의 목적은 태아의 초음파 도플러 신호로부터 태아 심박을 검출하는 알고리즘을 간단한 방법으로 개선하고자 한다. 신호 주기를 검출하는데 가장 널리 쓰이는 자기상관함수의 수정된 함수를 제안하고, 신호의 주기를 찾기 위해 설정하는 데이터 분석 구간의 크기와 이동 간격을 가변하도록 하였다. 제안된 방법은 실제 산모에게서 측정된 데이터에 적용하여 태아 심박의 beat-to-beat 검출이 가능함을 확인하였으며, 태아 심전도 신호와도 비교하였다. 제안하는 방법은 간단하면서도 효과가 있으므로 실제 장비에 적용될 수 있을 것으로 기대된다. Continuous fetal heart beat monitoring has assisted clinicians in assuring fetal well-being during antepartum and intrapartum. Fetal heart rate (FHR) is an important parameter of fetal health during pregnancy. The Doppler ultrasound is one of very useful methods that can non-invasively measure FHR. Although it has been commonly used in clinic, inaccurate heart rate reading has not been completely resolved.. The objective of this study is to improve detection algorithm of FHR from Doppler ultrasound signal with simple method. We modified autocorrelation function to enhance signal periodicity and adopted adaptive window size and shifted for data segment to be analysed. The proposed method was applied to real measured data, and it was verified that beat-to-beat FHR estimation result was comparable with the reference fetal ECG data. This simple and effective method is expected to be implemented in the embedded system.

의료기기 안전성 정보 원내 보고 시스템 설계

장혜정(Hye Jung Jang),최영득(Young Deuk Choi),김남현(Nam Hyun Kim) 대한전자공학회 2015 전자공학회논문지 Vol.52 No.1

본 연구는 의료기기법이 시행된 이래 의료기기 부작용등 안전성 정보관리를 위한 의료기기 안전성 정보 원내 보고 시스템 설계에 대한 연구이다. 본 연구는 현행 의료기기 부작용등 안전성정보 보고 관리에 대한 법적 규정 및 시스템에 대한 절차와 현황을 파악하고, MSF/CD(Microsoft Solution Framework/Component Design)설계방법론을 적용한 시스템 설계 방법을 적용하여 의료기기 안전성 정보 원내 보고 시스템 구축을 위한 설계를 하였다. 본 연구를 통해 우리나라의 부작용 등 안전성 정보보고에 대한 식품의약품안전처 고시 규정을 포함한 의료기기 관리 제도를 파악하고, 좀 더 환자의 안전과 의료기기의 위험관리를 효과적으로 할 수 있는 의료기기 안전성 정보 원내 보고 시스템을 설계 및 구축함으로써 의료기기 부작용 등 안전성 정보 보고의 활성화에 이바지 할 수 있기를 기대한다. In this study, medical devices safety information reporting system was designed to manage medical devices for the efficient management of in-hospital adverse events. The current management of medical device adverse event reporting regulations and the legal status of the system and procedures for identifying the system were reviewed. MSF/CD(Microsoft Solution Framework/Component Design) was applied to the system design. Through this study, we can understand medical devices management including the notice provisions of the Ministry of Food and Drug Safety for medical devices safety information reporting. We also expect this study will help to improve patient safety and the effective management of medical equipment, and contribute to activating medical devices safety information reporting.

말기신부전증으로 투석요법을 받는 환자의 신세포암

유호송 ( Ho Song Yu ),최영득 ( Young Deuk Choi ) 대한신장학회 2011 Kidney Research and Clinical Practice Vol.30 No.3

가중치 자가상관함수를 적용한 도플러 초음파 신호에서 태아 심박 검출

남기창(Ki Chang Nam),권자영(Ja Young Kwon),임종순(Joung Soon Lim),최영득(Young Deuk Choi) 대한전기학회 2012 정보 및 제어 심포지엄 논문집 Vol.2012 No.10

독립요소분석을 이용한 태아심전도 추출을 위한 시변 칼만 평활기의 개발

이충근(Chung Keun Lee),김봉수(Bong Soo Kim),권자영(Ja Young Kwon),최영득(Young Deuk Choi),송광섭(Kwang Soup Song),남기창(Ki Chang Nam) 대한전자공학회 2012 전자공학회논문지 Vol.49 No.10

태아심박의 모니터링은 태아의 안녕을 평가하기 위해 중요한 정보이다. 비관혈적인 태아심전도는 산모의 복부 신호로부터 추출될 수 있다. 따라서 산모 복부의 혼합 신호로부터 태아심전도를 추출하기 위해 많은 유망한 신호처리 방법들이 개발되어 왔다. 그러나 비관혈적인 태아심전도는 안정적인 신호 측정법이 부족하고 신호처리 방법의 어려움으로 여전히 임상에서 널리 적용되지 못하고 있다. 태아심전도를 추출하는 신호처리 결과는 가우시안 백색잡음에 의해 신호대잡음비가 낮아질 수 있다. 본 논문에서는 태아심전도에서 시간에 따라 변하는 백색잡음 신호를 제거하여 신호대잡음비를 높이기 위한 방법으로 시변 칼만 평활기를 제안하였고 그 가능성을 확인하였다. Wiener 과정을 시스템 모델로 설정하고 백색잡음 크기에 따라 공분산 행렬을 수정하였으며, 이를 통해 칼만 이득을 변화시켜 평활화 정도를 가변시킬 수 있도록 설계하였다. 5채널 태아심전도 모델을 이용하여 백색잡음의 크기에 따른 최적 공분산 행렬 값을 구하였고, 모의실험을 통해 제안된 방법의 가능성을 확인할 수 있었다. Fetal heart rate monitoring is important information to assess fetal well-being. Non-invasive fetal ECG (electrocardiography) can be derived from maternal abdominal signal. And various promising signal processing methods have been introduced to extract fetal ECG from mother’s composite abdominal signal. However, non-invasive fetal ECG monitoring still has not been widely used in clinical practice due to insufficient reliable measurement and difficulty of signal processing. In application of signal processing method to extract fetal ECG, it might be lower signal to noise ratio due to time varying white Gaussian noise. In this paper, time varying Kalman smoother is proposed to remove white noise in fetal ECG and its feasibility is confirmed. Wiener process was set as Kalman system model and covariance matrix was modified according to white Gaussian noise level. Modified error covariance matrix changed Kalman gain and degree of smoothness. Optimal covariance matrix according to various amplitude in Gaussian white noise was extracted by 5 channel fetal ECG model, and feasibility of proposed method could be confirmed.

전립선 적출술 후 요실금이 전립선암 환자의 건강 관련 삶의 질에 미치는 영향

김정현(Kim, Jeong Hyun),장연수(Jang, Yeon Soo),최영득(Choi, Young Deuk),오의금(Oh, Eui Geum) 한국성인간호학회 2019 성인간호학회지 Vol.31 No.3

Subcutaneous Interleukin-2 Monotherapy for Metastatic Renal Cell Carcinoma in Korean Patients

Jeong Ho Kim(김정호),Ki Soo Lee(이기수),Choung-Soo Kim(김청수),Young Deuk Choi(최영득),Tae Hyo Kim(김태효) 대한비뇨기종양학회 2021 대한비뇨기종양학회지 Vol.19 No.4

Purpose: This study was a prospective single-arm clinical trial aimed at assessing the efficacy and toxicity of subcutaneous interleukin (IL)-2 monotherapy in patients with metastatic renal cell carcinoma (RCC). Materials and Methods: We enrolled 26 patients with metastatic RCC in this multicenter controlled trial. The patients received subcutaneous injections of recombinant IL-2 (BMI-rh-IL2, an aldesleukin biosimilar, BMIKOREA Co., Ltd.) in 5-week cycles. In the first week, the patients received a subcutaneous IL-2 loading dose of 18×10<SUP>6</SUP> IU once on treatment days 1–5, followed by 2 days of rest. In the following 3 weeks, they received a dose of 18×10<SUP>6</SUP> IU via subcutaneous injection once on treatment days 1 and 2. Then, the patients received a dose of 9×10<SUP>6</SUP> IU via subcutaneous injection once on treatment days 3, 4, and 5, followed by 2 days of rest. The primary end point was the objective response rate; the secondary end points were progression-free survival (PFS) and safety. Results: Overall, 22 patients were included in the final per-protocol analysis. The objective response and the disease control rates were 13.64% (3 of 22), and 90.9% (20 of 22), respectively. The mean PFS was 5.55 months (95% confidence interval, 2.71–8.4). The proportion of patients who experienced a treatment-related grade 3 or 4 adverse event was 3.85% (1 of 26). There were no treatment-related deaths. Conclusions: In this study, the subcutaneous IL-2 monotherapy regimen demonstrated efficacy and safety comparable to those reported in previous studies of subcutaneous IL-2 monotherapy and was effective in Korean patients with metastatic RCC.

Association Between Prostate Cancer and 25-Hydroxyvitamin D2 Levels: National Health and Nutrition Examination Survey 2007-2008 Results

Jee Soo Park(박지수),Won Sik Jang(장원식),Sung Joon Hong(홍성준),Young Deuk Choi(최영득),Koon Ho Rha(나군호),Won Sik Ham(함원식) 대한비뇨기종양학회 2020 대한비뇨기종양학회지 Vol.18 No.1

Purpose: To report an association between prostate cancer and vitamin D levels among different races in a single population in the United States. Materials and Methods: We investigated whether there was an association between vitamin D level and prostate cancer in different races in the United States. We used data collected from 1,363 men during the National Health and Nutrition Examination Survey 2007–2008. Multivariate logistic regression analysis was used to evaluate the independent associations between vitamin D levels (not only 25-hydroxyvitamin D [25(OH)D], but also 25(OH)D2 and D3) and prostate cancer. Association between vitamin D levels and prostate specific antigen level was also analyzed in non-Hispanic white males without prostate cancer. Results: Older age was significantly associated with prostate cancer in all races (p<0.05), whereas vitamin D (p=0.024), especially 25(OH)D2 (p=0.027) was significantly higher only in non-Hispanic white males. There was no difference in vitamin D levels between non-Hispanic white males with a prostate specific antigen concentration >3 ng/mL and ≤3 ng/mL. Conclusions: This study revealed a positive association between vitamin D, especially 25(OH)D2, and prostate cancer only in non-Hispanic white males. And vitamin D was not associated with prostate specific antigen level causing detection bias.

높은 PSA수치 (>20ng/ml)를 보이는 국소전립선암의 치료

채윤병(Yunbyung Chae),정석현(Seok Hyun Chung),유호송(Ho Song Yu),최영득(Young Deuk Choi) 대한비뇨기종양학회 2010 대한비뇨기종양학회지 Vol.8 No.3

The definition of high risk prostate cancer is unclear. Generally preoperative PSA, Biopsy Gleason score and DRE characteristics are used to describe this group of patients. But until now, there is no consensus for these prostate cancers and manystudies report different methods of classification and different treatment options, ranging from hormonal therapy to prostatectomy. Thus, there is a need to clarify the definition and treatment of high risk prostate cancers, especially localized prostate cancer with high PSA. Herein we review the literatures on high risk prostate cancers and their oncologic outcomes.

전립선암으로 근치적 전립선적출술을 받은 한국인의 특징과 예후

김대성(Dae Sung Kim),변석수(Seok-Soo Byun),이상은(Sang Eun Lee),이은식(Eunsik Lee),최한용(Han Yong Choi),정병하(Byung Ha Chung),최영득(Young Deuk Choi),안한종(Hanjong Ahn),황태곤(Tae-Kon Hwang),이강현(Kang Hyun Lee),김원재(Wun-Jae Ki 대한비뇨기종양학회 2010 대한비뇨기종양학회지 Vol.8 No.1

Purpose: There is a great difference between the prostate cancer in Asian men compared to Western men. We evaluated the clinicopathologic features and prognosis of Korean men with prostate cancer who underwent radical prostatectomy. Materials and Methods: We reviewed retrospectively the clinicopathologic parameters including age, preoperative PSA, stage, Gleason score and so on in 2,783 men underwent radical prostatectomy in 14 institutions. Of 2,783 men, patients with prior radiotherapy, neoadjuvant treatment, suspicious lymph node invasion, distant metastasis and treatment failure were excluded. We evaluated recent change in clinical parameters. 2,081 men with localized prostate cancer were analyzed for the biochemical recurrence-free survival rates. Results: Proportion of patients with serum PSA of less than 10ng/ml were 38.9% in 1999. However the proportion were 68.6% in 2008. The 5-year overall biochemical recurrence-free survival rate (BCR-FS) was 48%. The 5-year BCR-FS according to the preoperative serum PSA, biopsy Gleason score, pathologic T stage, margin positivity had the lower level than Western series. Conclusions: The proportion of patients with serum PSA <10ng/ml were increased in Korean men with prostate cancer. However, the BCR-FS had the lower level than Western men. Therefore, we must consider that the prostate cancer in Korean men have a unfavorable prognosis compared with Western men.