디스플레이 및 이미징 시스템으로의 응용을 위한 3D 프린팅 기반 맞춤형 광학 요소의 개발

학위논문 (박사) -- 서울대학교 대학원 : 공과대학 전기·정보공학부, 2021. 2. 홍용택.일반적으로 제조 공정은 절삭 방식과 적층 방식으로 구분된다. 이 중에서 적층 방식 공정은 저비용 및 단시간으로 복잡한 형태의 구조를 만들 수 있어서 이에 대한 연구와 개발이 꾸준히 진행되어왔다. 특히 3D 프린팅은 적층 방식 공정 중에서 가장 대표적인 방법으로, 기계 부품 및 생체 기관 제조 등의 분야에서는 이미 상용화가 진행되고 있다. 하지만 전자 소자 및 광학 요소 분야에서의 3D 프린팅의 활용은 여전히 연구 개발 또는 시제품 제작 단계에 머무르고 있다. 특히 마이크로 렌즈, 컬러 필터 등이 3D 프린팅으로 응용할 수 있는 가장 가능성 있는 광학 요소로서 디스플레이 및 이미징 시스템에 널리 사용될 것으로 예상되지만 여전히 상용화를 위한 연구가 진행 중이다. 또한 3D 프린팅을 이용한 광학 요소의 제작은 소재, 길이 스케일, 형상 및 응용 방안 등에서도 제한이 많은 상황이다. 따라서 이러한 문제를 극복하기 위해서는 디스플레이 및 이미징 시스템에서의 3D 프린팅 된 광학 요소의 유용성을 확장해야 하며, 다음과 같이 세 가지 측면에서 향상된 성능을 달성해야 한다. 첫째, 다양한 방식의 3D 프린팅 방법을 통해 마이크로미터에서 센티미터까지 광범위의 길이 스케일을 가지는 구조물의 제작이 가능해야 한다. 둘째, 임의의 곡면, 계층적 구조 등 복잡한 형상의 구조물을 쉽게 제작할 수 있어야 한다. 셋째, 단단한 소재 대신 탄성체와 같은 소프트 소재를 이용하여 광학적인 기능을 용이하게 조절할 수 있어야 한다. 이와 같은 동기를 바탕으로 본 학위 논문에서는 디스플레이 및 이미징 시스템으로의 응용을 위한 3D 프린팅 기반 맞춤형 광학 요소의 개발에 대한 내용을 보고한다. 3D 프린팅 기반 광학 요소를 매크로 스케일, 마이크로 스케일 그리고 매크로 및 마이크로 스케일이 혼합된 계층적 구조 등 세 가지 유형으로 분류하고 각각에 대한 응용 분야를 제시한다. 매크로 스케일의 광학 요소로는 가장 기본적인 요소인 렌즈와 거울을 선택한다. 렌즈는 공압식 디스펜싱 방법을 이용하여 실린드리컬 쌍 형태로 제작되었으며, 심리스 모듈러 평판식 디스플레이의 구현을 위해 적용된다. 또한 용융 적층 방식의 3D 프린팅으로 만들어진 몰드를 이용하여 거울을 제작하고, 이를 이용하여 심리스 모듈러 커브드 엣지 디스플레이를 구현한다. 이와 같이 모듈러 디스플레이의 이음새 부분에 3D 프린팅으로 제작된 렌즈 또는 거울을 부착하는 방식으로 화면을 심리스로 확장하는 기술을 제시하고, 다양한 형태의 디스플레이에 적용할 수 있는 가능성을 보여준다. 마이크로 스케일의 광학 요소로는 발광 다이오드에서 색 변환과 광 추출 기능을 동시에 나타내는 색 변환 마이크로 렌즈를 선택한다. 양자 점/광 경화성 고분자 복합체의 전기수력학적 프린팅을 통해 양자 점이 내장된 다양한 형태의 색 변환 마이크로 렌즈를 제작하며, 이를 청색 마이크로 발광 다이오드 어레이의 발광부 상에 적용하여 풀 컬러 마이크로 발광 다이오드 디스플레이로의 응용 가능성을 제시한다. 마지막으로 매크로 및 마이크로 스케일이 혼합된 계층적 구조의 광학 요소로서 디스펜싱 및 건식 러빙 과정의 조합으로 제작된 겹눈 형태를 모사한 렌즈 구조를 제시한다. 반구 형태의 매크로 렌즈를 디스펜싱으로 형성하고, 매크로 렌즈의 곡면 상에 단층의 마이크로 입자의 배열을 얻기 위해 건식 러빙 공정을 진행한다. 이러한 방식으로 형성된 계층적 구조가 소프트한 소재로 복제되어서 신축성을 가지는 겹눈 형태 모사 구조가 완성된다. 마이크로 렌즈 어레이는 매크로 렌즈의 표면을 따라 형성되고 리지드 아일랜드로 역할을 하여, 전체 계층적 구조에 기계적 변형이 가해져 매크로 렌즈의 모양이 변형되어도 마이크로 렌즈는 형상과 해상도, 초점 거리 등의 광학적 특성을 유지할 수 있다. 본 학위 논문은 3D 프린팅을 이용하여 다양한 형태와 스케일의 광학 요소를 제작하고 디스플레이 및 이미징 시스템으로의 여러 응용을 보여줌으로서 앞으로의 새로운 연구 및 개발 방향성을 제시하는 것을 주요 목적으로 한다. 3D 프린팅 설비의 단가가 낮아지고 정밀도 및 해상도가 높아지는 추세에 따라, 광학 요소를 쉽게 만들고 응용할 수 있는 맞춤형 광학 또는 스스로 구현하는 광학 분야가 변형 가능하고 멀티 스케일의 광학계로 점차 확대될 것으로 예상된다. 궁극적으로는 차세대 디스플레이 및 이미징 시스템에 필요한 광학 요소를 위한 기술의 저변을 넓히고, 이를 산업 전반에 응용할 수 있는 기반을 마련하고자 한다.Generally, the manufacturing process is divided into the subtractive (top-down) type and additive type (bottom-up). Among them, the additive manufacturing process has attracted a lot of attention because it can manufacture products with complex shapes in a low-cost and short-time process. In particular, three-dimensional (3D) printing is a representative method, which has already been commercialized in the field of mechanical components and biomedical organ. However, it remains in the research and development step in the field of electronic devices and optical components. Especially, although 3D printed optical components including microlens and color filter are expected to be widely used in display and imaging systems, it is still under investigation for commercialized products, and there are limitations in terms of materials, length scale, shape, and practical applications of components. Therefore, to overcome these issues, it is required for investigating and expanding the potential usefulness for 3D printed optical components in display and imaging systems to achieve better performance, productivity, and usability in three aspects. First, it should be possible to manufacture structures with a wide range of length scales from micrometer to centimeter through various 3D printing methods. Second, complex shapes such as free-from curved surfaces and hierarchical structures should be easily fabricated. Third, it is necessary to add functionality by manufacturing structures in which tunable functions are introduced using soft materials like an elastomer. Based on the above motivations, 3D printing-based customized optical components for display and imaging system applications are introduced in this dissertation. 3D printed optical components are classified into three types and their applications are showed to verify the scalability of 3D printing: macro-scale, microscale, and hierarchical macro/micro-scale. As macro-scale printed optical components, lens and mirror which are the most basic optical components are selected. The lens is fabricated by a pneumatic-type dispensing method with the form of a cylindrical pair and adopted for demonstration of seamless modular flat panel display. Besides, a seamless modular curved-edge display is also demonstrated with a mirror, which is fabricated from fused deposition modeling (FDM)-type 3D printed mold. By simply attaching a printed lens or mirror onto the seam of the modular display, it is possible to secure seamless screen expansion technology with the various form factor of the display panel. In the case of micro-scale printed optical components, the color-convertible microlens is chosen, which act as a color converter and light extractor simultaneously in a light-emitting diode (LED). By electrohydrodynamic (EHD) printing of quantum dot (QD)/photocurable polymer composite, QD-embedded hemispherical lens shape structures with various sizes are fabricated by adjusting printing conditions. Furthermore, it is applied to a blue micro-LED array for full-color micro-LED display applications. Finally, a tunable bio-inspired compound (BIC) eyes structure with a combination of dispensing and a dry-phase rubbing process is suggested as a hierarchical macro/micro-scale printed optical components. A hemispherical macrolens is formed by the dispensing method, followed by a dry-phase rubbing process for arranging micro particles in monolayer onto the curved surface of the macrolens. This hierarchical structure is replicated in soft materials, which have intrinsic stretchability. Microlens array is formed on the surface of the macrolens and acts as a rigid island, thereby maintaining lens shape, resolution, and focal length even though the mechanical strain is applied to overall hierarchical structures and the shape of the macrolens is changed. The primary purposes of this dissertation are to introduce new concepts of the enabling technologies for 3D printed optical components and to shed new light on them. Optical components can be easily made as 3D printing equipment becomes cheaper and more precise, so the field of Consumer optics or Do it yourself (DIY) optics will be gradually expanded on deformable and multi-scale optics. It is expected that this dissertation can contribute to providing a guideline for utilizing and customizing 3D printed optical components in next-generation display and imaging system applications.Chapter 1. Introduction 1 1.1. Manufacturing Process 1 1.2. Additive Manufacturing 4 1.3. Printed Optical Components 8 1.4. Motivation and Organization of Dissertation 11 Chapter 2. Macro-scale Printed Optical Components 15 2.1. Introduction 15 2.2. Seamless Modular Flat Display with Printed Lens 20 2.2.1. Main Concept 20 2.2.2. Experimental Section 23 2.2.3. Results and Discussion 26 2.3. Seamless Modular Curved-edge Display with Printed Mirror 32 2.3.1. Main Concept 32 2.3.2. Experimental Section 33 2.3.3. Results and Discussion 36 2.4. Conclusion 46 Chapter 3. Micro-scale Printed Optical Components 47 3.1. Introduction 47 3.2. Full-color Micro-LED Array with Printed Color-convertible Microlens 52 3.2.1. Main Concept 52 3.2.2. Experimental Section 54 3.2.3. Results and Discussion 57 3.3. Conclusion 65 Chapter 4. Hierarchical Macro/Micro-scale Printed Optical Components 66 4.1. Introduction 66 4.2. Tunable Bio-inspired Compound Eye with Printing and Dry-phase Rubbing Process 69 4.2.1. Main Concept 69 4.2.2. Experimental Section 71 4.2.3. Results and Discussion 73 4.3. Conclusion 79 Chapter 5. Conclusion 80 5.1. Summary 80 5.2. Limitations and Suggestions for Future Researches 83 References 88 Abstract in Korean (국문 초록) 107Docto

고신뢰 짧은 패킷 전송을 위한 깊은 신경망을 이용한 희소 벡터 복호에 관한 연구

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 전기·정보공학부, 2019. 2. 심병효.Ultra-reliable and low latency communication (URLLC) is one of the prospective service categories in 5G to be useful in the future hyper-connective industrial field. To support its requirements, 3rd Generation Partnership Project (3GPP) sets an aggressive standard that a packet should be delivered within 1 ms transmission period with an accuracy of 99.999%. Since the current 4G systems designed to maximize the coding gain by transmitting capacity achieving long codeblock resulting in an increase of the latency. A recently proposed approach for the short packet transmission is sparse vector coding (SVC). In SVC, encoding is done by simple sparse mapping and spreading to formulate the system model into an underdetermined system and replaces the decoding process with a simple sparse recovery algorithm. In this paper, we propose a deep neural network-based approach, referred to as deep sparse vector decoding (deep-SVD), to enhance the performance of SVC to better meet the URLLCs extreme requirements. To this end, we reformulate the SVC-decoding process as a multi-label classification and build the network to learn the highly correlated relationship within codebook. Numerical results demonstrate that the proposed deep-SVD outperforms the conventional SVC decoding in both reliability and latency.URLLC (Ultra Reliability and Low Latency Communication)는 미래의 초연결 산업 분야에서 주목받는 5G 서비스 카테고리 중 하나이다. 3GPP (Third Generation Partnership Project)는 URLLC을 실현하기 위한 요구조건으로 1ms 전송 시간 내에 99.999%의 정확도로 패킷을 전송해야 한다는 다소 까다로운 기준을 설정하였다. 현재의 4G 무선통신 시스템에서는 복잡하고 긴 코드 블록을 전송함으로써 코딩 이득을 최대화하도록 설계하여 정확성을 높이지만 그로 인하여 지연 시간이 길어진다는 단점이 있다. 최근 URLLC를 대상으로 짧은 패킷 전송을 위한 SVC (Sparse Vector Coding) 기법이 제안되었다. SVC에서의 인코딩은 단순한 희소 신호 매핑 및 확산을 하여 패킷을 전송하며 디코딩은 간단한 희소 벡터 복원 알고리즘으로 대체한다. 이 논문에서는 URLLC의 높은 요구조건을 만족하기 위해서 깊은 신경망 기반의 deep sparse vector decoding (Deep-SVC) 기법을 제안한다. 이를 위해서, 우리는 SVC의 디코딩 과정을 다중 레이블 분류 (multi-label classification)으로 재구성한다. 그리고 깊은 신경망을 구성하여 코드북 내의 높은 상관관계를 학습하여 SVC 디코딩 과정의 성능을 끌어올린다. 실험을 통하여 우리는 제안하는 Deep-SVD 기법이 기존의 SVC 디코딩 기법보다 더 좋은 정확성을 갖음을 보인다.1. Introduction 2. Short Packet Transmission Using Sparse Vector Coding 3. Sparse Vector Decoding via DNN 4. Simulation 5. ConclusionMaste

Association between the neutrophil-to-lymphocyte ratio and intravesical prostatic protrusion in men with benign prostatic hyperplasia

OBJECTIVE: To analyze the association between neutrophil-to-lymphocyte ratio (NLR) and intravesical prostatic protrusion (IPP) in men with benign prostatic hyperplasia. METHODS: Two hundred and fifty men aged >50 years who presented with lower urinary tract symptoms at our institution between 2014 and 2018 were analyzed. Pearson's method was used for analysis of the correlation between NLR and IPP. Multivariate logistic regression analysis was used to identify predictors of IPP. Further analysis according to total prostate volume (TPV) was performed. RESULTS: The NLR correlated positively with IPP (Pearson's r = 0.459, P < 0.001) and was an independent predictor of IPP ≥10 mm (odds ratio, 2.95; 95% confidence interval, 1.59-5.47; P = 0.0006). Among the 142 men with prostates <40 cm3 , mean NLR was 2.50 ± 0.71 in those with IPP ≥10 mm and 1.71 ± 0.57 in those with IPP < 10 mm (P < 0.001). The NLR differed significantly between those with a prostate <40 cm3 and IPP ≥10 mm and those with a larger prostate and IPP < 10 mm (2.50 ± 0.71 vs 2.07 ± 0.77, respectively; P = 0.020). CONCLUSIONS: NLR can be used as a surrogate marker for presence of IPP. Its clinical value would be especially important in men with a small prostate gland but high IPP. The NLR seemed to be more strongly correlated with IPP than with TPV.ope

DC Motor Velocity Control using Fuzzy PID Controller based on Kalman Filter with Nonlinear Friction Estimator

산업현장에서 많이 쓰이는 DC 모터는 부하가 연결됨에 따라 마찰 토크의 영향을 받게 된다. 마찰 토크는 크게 정지 마찰 토크, 점성 마찰 토크, 쿨롱 마찰 토크 세 가지로 구분되는데, 이중에서 쿨롱 마찰 토크는 비선형 마찰 토크로서 모터의 제어 성능을 저하시키는 주요한 원인으로 작용되고, 사용자가 원하는 모터의 각속도를 출력하지 못하도록 한다. 또한 모터시스템은 시스템 잡음과 측정 잡음의 영향으로 인하여 정상상태에서 채터링하는 현상을 가지며 이로 인해 정상상태 제어 성능이 저하되는 원인이 된다. DC 모터 속도 제어시스템에 있어서 잡음의 영향으로 인하여 정상상태에서 성능저하 현상을 해결하기 위하여 칼만 필터 기반의 퍼지 PID 제어시스템을 구성하였다. 구성된 제어시스템을 대상으로 시뮬레이션을 수행한 결과 잡음의 영향은 크게 감소하여 안정된 출력을 나타냈지만, 시스템에 작용하는 쿨롱 마찰 토크의 영향으로 인해서 각속도가 기준입력에 도달하지 못하고 정상상태오차를 나타내었다. 그 이유는 칼만 필터 알고리즘에 모터 시스템의 입력 전압과 같은 알려진 입력만 반영되고 비선형 마찰인 쿨롱 마찰 토크와 같은 미지의 입력은 반영되지 않았기 때문이다. 다시 말하면, 시스템의 실제 상태와 필터 추정치 사이의 추정 오차가 커지게 되고, 이러한 경우 이노베이션 프로세스의 값은 커지지만 칼만 이득은 작아서 필터의 보상이 제대로 이루어지지 않기 때문에 정상상태에서 추정 오차를 0으로 수렴시킬 수 없기 때문이다. 위와 같은 문제를 해결하기 위해 칼만 필터의 이노베이션 프로세스를 이용하여 쿨롱 마찰 토크를 추정하는 마찰 추정기 구성방법을 제안하였다. 마찰 추정기로부터 추정된 마찰 토크를 퍼지 PID 제어기의 제어입력에 피드백 시킴으로써 마찰 토크를 보상할 수 있는 새로운 제어입력을 생성하는데 사용하고 또한 칼만 필터의 정확한 상태 추정에 활용하도록 한다. 이와 같은 기능을 통합한 마찰 추정기를 가진 칼만 필터 기반의 퍼지 PID 제어시스템을 제안하였고 DC 모터의 속도 제어시스템 문제에 적용하였다. 비선형 쿨롱 마찰 토크가 인가되는 부하가 결합된 DC 모터의 속도 제어시스템을 대상으로 시뮬레이션을 수행하였으며, 그 결과를 바탕으로 제안된 제어시스템의 성능검증과 타당성을 입증하였다.|Most DC motors used in industrial field are affected by friction torque as mechanical loads are connected. There are three types of friction torques such as static friction torque, viscous friction torque, and Coulomb friction torque. Static friction torque is transformed into Coulomb friction torque as soon as DC motor starts. The magnitude of viscous friction torque is assumed to be proportional to the motor angular velocity and it is linearly modeled, so that its effect is eventually contained into mathematical model of DC motor velocity control system. By the way, the type of Coulomb friction torque is nonlinear step function depending on the direction of DC motor angular velocity. By this reason, Coulomb friction torque can not be linearly modeled and thus is not contained into mathematical model of DC motor velocity control system when mechanical load is connected to DC motor. Especially, in case that excessive Coulomb friction torque is exerted, the steady state output of DC motor velocity control system is not asymptotically converged to reference input and exhibits finite steady state error. In order to solve this phenomenon, in this paper, a fuzzy PID control system based on Kalman filter is composed for the DC motor velocity control system subjected to system noise and measurement noise. The simulation results for this control system address that the chattering phenomenon on output by noises is normally regulated, while steady state error is occurred due to the excessive Coulomb friction torque in spite of the PID control action. As a result, it is known that the unknown Coulomb friction torque must inevitably be estimated to improve the steady state response. At first, a method to comprise friction estimator is suggested, by using innovation process of Kalman filter. The idea to comprise friction estimator is as follows: When Kalman filter can not estimate of the state of the given control system, the stochastic average of the innovation process does not converge to zero. It means that the estimation error does not converge to zero. Therefore, it is possible to estimate unknown Coulomb friction torque based on innovation process of the Kalman filter. At second, the estimated Coulomb friction torque is fed back to compensate to predicted estimate of Kalman filter and also to generate a new control input by adding it to the output of the fuzzy PID controller. Therefore, a method to comprise control system, named fuzzy PID control system based on Kalman filter with friction estimator, was suggested for DC motor velocity control system. In order to verify the control performance of the suggested control system several simulations were accomplished. By analyzing the simulation results, the effectiveness of the suggested control system was assured.List of Figures ⅲ List of Tables ⅴ Abstract ⅵ 요약 ⅷ 제 1 장 서 론 1 1.1 연구배경 1 1.2 논문의 구성 3 제 2 장 DC 모터 속도 시스템의 모델링 4 2.1 부하가 결합된 DC 모터 속도 시스템 4 2.2 마찰 토크의 모델링 8 2.2.1 정지 마찰 8 2.2.2 쿨롱 마찰 9 2.2.3 점성 마찰 9 2.3 부하가 연결된 DC 모터 시스템 시뮬레이션 10 제 3 장 칼만 필터 기반의 퍼지 PID 제어 시스템 14 3.1 칼만 필터 알고리즘 15 3.2 칼만 필터 기반의 퍼지 PID 제어기 알고리즘 17 3.2.1 퍼지 PID 제어기 기본구조 18 3.2.2 퍼지화 알고리즘 19 3.2.3 퍼지 제어 규칙 22 3.2.4 비퍼지화 알고리즘 24 3.2.5 퍼지 PID 제어기 출력 25 3.3 칼만 필터 기반의 퍼지 PID 제어기를 사용한 DC 모터 속도 제어시스템 시뮬레이션 26 제 4 장 마찰 추정기를 가진 칼만 필터 기반의 퍼지 PID 제어 시스템 31 4.1 쿨롱 마찰 토크와 잡음이 인가되는 시스템 31 4.2 이노베이션 기반의 마찰 추정 알고리즘 33 4.2.1 퍼지 추정기의 기본 구조 33 4.2.2 퍼지 추정 퍼지화 알고리즘 35 4.2.3 퍼지 추정 규칙 38 4.2.4 비퍼지화 알고리즘 40 4.2.5 퍼지 마찰 추정기 출력 41 4.3 마찰 추정기를 가진 칼만 필터 기반의 퍼지 PID 제어 알고리즘 45 4.4 마찰 추정정기를 가진 칼만 필터 기반의 퍼지 PID 제어기를 사용한 DC 모터 시스템 시뮬레이션 47 제 5 장 결 론 52 참고문헌Maste

The Association of A Number of Predictive Factors for The Recurrence of Papillary Urothelial Neoplasm of Low Malignant Potential: Prognostic Analysis From Multiple Academic Centers.

PURPOSE: To identify clinically useful predictors for the recurrence of papillary urothelial neoplasm of low malignant potential (PUNLMP), we reviewed the clinical information of patients who were diagnosed and treated in multiple tertiary-care academic facilities. MATERIALS AND METHODS: Between February 2007 and April 2015, 95 patients diagnosed with PUNLMP after transurethral resection of bladder (TURB) were included in this study. Age, gender, body mass index, smoking history, the presence or absence of previous history of urothelial neoplasm, the presence or absence of gross hematuria, cytological results at the time of diagnosis, tumor diameter, and multiplicity of tumor were estimated as variablesfor analysis. Cox regression tests were used for identifying predictive factors for recurrence of PUNLMP. RESULTS: Sixty-nine cases of PUNLMP were de novo primary bladder PUNLMPs without known urothelial lesions in the urinary tract, and 26 PUNLMPs were identified on surveillance biopsies of patients with a previous history of urothelial neoplasm. During the follow-up period, recurrences developed in 13 patients (13.7%). Recurrence rates were 4.2% and 9.5% at 12 and 24 months, respectively. On univariate and multivariate Cox regression analyses, previous history of urothelial neoplasm [95% confidence interval (CI): 0.057-0.604, hazard ratio (HR) = 0.185, P = .005] and multiplicity of tumors [95% CI = 0.064-0.584, HR = 0.193, P = .004] were identified as independent predictors for recurrence-free survival of patients with PUNLMP. CONCLUSION: Tumor multiplicity and previous history of urothelial neoplasm are independent prognostic factors forprediction of recurrence of PUNLMP. More careful and closer follow-up should be recommended for PULNMPpatients with tumor multiplicity or a previous history of urothelial neoplasm.ope

Current role of treatment in men with lower urinary tract symptoms combined with overactive bladder

Lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH) are highly prevalent in older men. The storage subcategory of LUTS is synonymous with overactive bladder (OAB) syndrome, which is an empirical diagnosis. Traditionally, alpha-blockers are widely prescribed to manage the LUTS of BPH, although storage symptoms may persist in many men despite treatment. Therefore, because therapies that target the prostate often fail to alleviate storage symptoms, they may not be the appropriate therapy for OAB. In past years, most physicians appeared to give more weight in elderly men to voiding symptoms than to storage symptoms and to be more concerned with initial treatment with anticholinergics for males with storage symptoms. Considering the recent increase in data on the efficacy and safety of combination treatment with alpha receptor antagonists and antimuscarinic agents, the standard pharmacologic treatment of patients with LUTS combined with OAB should be an alpha receptor antagonist and an antimuscarinic agent. Beta-3 adrenoreceptor agonists may also potentially be useful for the treatment of male LUTS combined with OAB.ope

Management of Patients With Advanced Prostate Cancer: Establishment of Treatment Guidelines Through Prostate Cancer Summit (PCAS) 2016 Composed of Korean Prostate Cancer Experts

Purpose: The Advanced Prostate Cancer Consensus Conference (APCCC) 2015 was based on topics with controversy in the field of advanced prostate cancer. To understand the Korean urologists perspective regarding the issues, we have conducted a questionnaire named Prostate Cancer Summit (PCAS) 2016, with 9 important subtopics Materials and Methods: Total 9 subtopics have been decided and questions were developed regarding each subtopic. The questions were based on that of APCCC 2015 and translated into Korean for better understanding. Total 51 panelists have voted online on 85 different questions. Results: The survey concluded that testosterone should be measured as a diagnostic criterion for castration resistance prostate cancer (CRPC) and that consensus was reached on issues such as the use of androgen receptor pathway inhibitors in the treatment of predocetaxel and postdocetaxel in CRPC patients. In addition, 76% of the participants agreed that imaging tests were needed before new treatment in CRPC patients, and a majority of participants agreed that periodic imaging tests are necessary regardless of symptoms during treatment for CRPC. However, some issues, such as the use of prostate-specific antigen-based triggers for remediation in CRPC patients, the endocrine manipulation in nonmetastatic CRPC patients, and the onset of treatment in asymptomatic metastatic CRPC patients, were not agreed. Conclusions: The results from PCAS 2016 has addressed some of the issues with controversy. Although the voting results are subjective, it will help guide treatment decisions in topics with less evidence.ope

Patient Safety in Spine Surgery: Regarding the Wrong-Site Surgery

Patient safety regarding wrong site surgery has been one of the priority issues in surgical fields including that of spine care. Since the wrong-side surgery in the DM foot patient was reported on a public mass media in 1996, the wrong-site surgery issue has attracted wide public interest as regarding patient safety. Despite the many wrong-site surgery prevention campaigns in spine care such as the operate through your initial program by the Canadian Orthopaedic Association, the sign your site program by the American Academy of Orthopedic Surgeon, the sign, mark and X-ray program by the North American Spine Society, and the Universal Protocol program by the Joint Commission, the incidence of wrong-site surgery has not decreased. To prevent wrong-site surgery in spine surgeries, the spine surgeons must put patient safety first, complying with the hospital policies regarding patient safety. In the operating rooms, the surgeons need to do their best to level the hierarchy, enabling all to speak up if any patient safety concerns are noted. Changing the operating room culture is the essential part of the patient safety concerning spine surgery.ope

Current status of active surveillance in prostate cancer.

Active surveillance (AS) is a management strategy involving close monitoring the course of disease with the expectation to intervene if the cancer progress, in a super-selected group of low-risk prostate cancer (PCa) patients. Determining AS candidates should be based on careful individualized weighing of numerous factors: life expectancy, general health condition, disease characteristics, potential side effects of treatment, and patient preference. Several protocols have been developed to determine insignificant PCa for choosing ideal AS candidates. Results regarding disease reclassification during AS have been also reported. In an effort to enhance accuracy during selection of AS candidate, there were several reports on using magnetic resonance imaging for prediction of insignificant PCa. Currently, there is an urgent need for further clinical studies regarding the criteria for recommending AS, the criteria for reclassification on AS, and the schedule for AS. Considering the racial differences in behavior of PCa between Western and Asian populations, more stringent AS protocols for Asian patients should be established from additional, well-designed, large clinical studies.ope

Clinical Efficacy and Safety of Naftopidil Treatment for Patients with Benign Prostatic Hyperplasia and Hypertension: A Prospective, Open-Label Study.

PURPOSE: To investigate the efficacy and safety of naftopidil for benign prostatic hyperplasia (BPH) patients, mainly focusing on changes in blood pressure (BP). MATERIALS AND METHODS: Of a total of 118 patients, 90 normotensive (NT) and 28 hypertensive (HT) patients were randomly assigned to be treated with naftopidil 50 mg or 75 mg for 12 weeks, once-daily. Safety and efficacy were assessed by analyzing changes from baseline in systolic/diastolic BP and total International Prostate Symptom Score (IPSS) at 4 and 12 weeks. Adverse events (AEs), obstructive/irritative subscores, quality of life (QoL) score, maximum urinary flow rate (Qmax), and benefit, satisfaction with treatment, and willingness to continue treatment (BSW) questionnaire were also analyzed. RESULTS: Naftopidil treatment decreased mean systolic BP by 18.7 mm Hg for the HT 50 mg group (p86% of all patients agreed to continue their current medications. CONCLUSION: Our results suggest that naftopidil treatment in BPH patients with hypertension allows for optimal management of BP within the normal range.ope