• 제목/요약/키워드: tomography.

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Primary Diffuse Large B-Cell Lymphoma of the Seminal Vesicle: a Case Report

  • Kwag, Kyung Su;Jang, Suk Ki;Yeon, Jae Woo;Kwon, Kye-Won;Son, Jeong Hwan;Kim, Hyuk Jung
    • Investigative Magnetic Resonance Imaging
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    • 제20권4호
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    • pp.259-263
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    • 2016
  • Primary diffuse large B-cell lymphoma of the seminal vesicle is an extremely rare disorder, with only two cases reported in the English literature. Here, we present imaging findings of a case of primary diffuse large B-cell lymphoma of the seminal vesicle. On transrectal ultrasonography, the mass presented as a 3.0-cm-sized heterogeneous, hypoechoic lesion in the right seminal vesicle. Computed tomography (CT) revealed a mass with rim-like enhancement in the right seminal vesicle. On magnetic resonance imaging (MRI), the tumor showed iso-signal intensity on T1-weighted images and heterogeneously intermediate-high signal intensity on T2-weighted images. The tumor showed rim-like and progressive enhancement with non-enhancing portion on dynamic scanning. Diffusion restriction was observed in the mass. On fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) imaging, a high standardized uptake value (maxSUV, 23.5) by the tumor was noted exclusively in the right seminal vesicle.

Air-coupled ultrasonic tomography of solids: 1 Fundamental development

  • Hall, Kerry S.;Popovics, John S.
    • Smart Structures and Systems
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    • 제17권1호
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    • pp.17-29
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    • 2016
  • Ultrasonic tomography is a powerful tool for identifying defects within an object or structure. But practical application of ultrasonic tomography to solids is often limited by time consuming transducer coupling. Air-coupled ultrasonic measurements may eliminate the coupling problem and allow for more rapid data collection and tomographic image construction. This research aims to integrate recent developments in air-coupled ultrasonic measurements with current tomography reconstruction routines to improve testing capability. The goal is to identify low velocity inclusions (air-filled voids and notches) within solids using constructed velocity images. Finite element analysis is used to simulate the experiment in order to determine efficient data collection schemes. Comparable air-coupled ultrasonic signals are then collected through homogeneous and isotropic solid (PVC polymer) samples. Volumetric (void) and planar (notch) inclusions within the samples are identified in the constructed velocity tomograms for a variety of transducer configurations. Although there is some distortion of the inclusions, the experimentally obtained tomograms accurately indicate their size and location. Reconstruction error values, defined as misidentification of the inclusion size and position, were in the range of 1.5-1.7%. Part 2 of this paper set will describe the application of this imaging technique to concrete that contains inclusions.

Computed Tomography에 의한 절편영상의 추정 (Estimate for Sliced Images by Computed Tomography)

  • 박미경;이의택
    • 전자통신동향분석
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    • 제12권6호통권48호
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    • pp.50-57
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    • 1997
  • CT스캔(Computed Tomography)은 다양한 분야에서 효과적으로 응용되고 있고, 특히 의학 영상에서 비침범 진단, 수술 계획 등에 커다란 영향을 끼쳤다. 이 글에서는 여러 가지 CT스캔의 종류, 그 수학적인 원리와 기본적인 평행 광선(parallel beam)을 이용한 영상의 재구축 알고리즘, 데이터의 추정과 문제점 그리고 그 개선 방향에 대해 논한다

SS-OCT 방식을 이용한 생체의 표피단면 영상 획득 (Acquirement of in vivo epidermal cross-sectional image by using swept source optical coherence tomography)

  • 김훈섭;임해진;엄진섭
    • 산업기술연구
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    • 제28권A호
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    • pp.163-166
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    • 2008
  • In this paper, the swept source optical coherence tomography system has realized using a free-space interferometer based on a beam splitter. Personal computer has completed the control for tunable wavelength laser digitally and the B-scan motor as well. From each experiment for an onion and a salmon egg, we confirmed that the in vivo epidermal cross-sectional images for them can be obtained appropriately.

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Tomographic Reconstruction of Two-Phase Flows

  • Ko, Han-Seo;Kim, Yong-Jae
    • Journal of Mechanical Science and Technology
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    • 제17권4호
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    • pp.571-580
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    • 2003
  • Tomography has been investigated to observe bubble behaviors in two-phase flows. A bubbly flow and an annular flow have been reconstructed by tomography methods such as an algebraic reconstruction technique (ART) and a multiplicative algebraic reconstruction technique (MART) . Computer synthesized phantom fields have been used to calculate asymmetric density distributions for limited cases of 3, 5, and 7 projection angles. As a result of comparison of two tomography methods, the MART method has shown a significant improvement in the reconstruction accuracy for analysis of the two-phase flows.

2극 수직자계를 이용한 Magnetic Tomograpy의 설계와 제작 (Design and Development of the Magnetic Tomography System Using Two Poles Perpendicular Magnetic Field)

  • 박은식;박관수
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제52권2호
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    • pp.61-67
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    • 2003
  • This paper describes a development of magnetic tomography system using two poles perpendicular magnetic field. In the system, the relative permeabilities of the object are detected by Hall sensors located along with tube circumference. The signals according to the size and position of the object could be separated in case the relative permeability of the object are over 10. Moreover, the size and location of the object could be determined in real time.

외과학과 근관치료학 영역에서 콘빔형전산화단층영상 활용 (Using cone-beam computed tomography in oral surgery and endodontics)

  • 김규태
    • 대한치과의사협회지
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    • 제48권10호
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    • pp.729-737
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    • 2010
  • The use of cone-beam computed tomography(CBCT) image has been increased. Usually, the dentists use this images for the implant or orthodontic treatment. In this article, CBCT examples for oral surgery and endodontics are presented. CBCT is very useful when dentists extract teeth or provide endodontic treatment. The disadvantage of the CBCT image is also discussed simply. Clinicians could provide higher quality of medical care with CBCT.

폐암에서 PET의 역할 (The Role of PET in Lung Cancer)

  • 김병태
    • 대한핵의학회지
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    • 제36권1호
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    • pp.28-33
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    • 2002
  • Lung cancer has become a loading cause of cancer death in Korea. Positron emission tomography was introduced in clinical nuclear medicine in the early 1990s and many studios using this functional imaging technology were performed for evaluation of its clinical utility. I review the current role of positron emission tomography in the diagnosis, staging, and therapy monitoring of lung cancer.

Refraction traveltime tomography using damped monochromatic wavefield

  • Pyun, Suk-Joon;Shin, Chang-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.441-448
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    • 2003
  • Refraction tomography requires an algorithm for efficiently computing the traveltimes and their $Fr\'{e}chet$ derivatives. We have attempted to solve the damped wave field using the frequency domain finite element model ing and then invoked the reciprocity theorem to calculate the $Fr\'{e}chet$ derivative of the traveltime with respect to the subsurface parameter. Then, we used a damped least square method to invert the traveltimes of the Marmousi 2 model. Numerical tests demonstrate that the refraction tomography with large aperture data can be used to estimate the smooth velocity model for the prestack depth migration.

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