• 제목/요약/키워드: medical imaging

검색결과 4,137건 처리시간 0.032초

Multiparametric Functional Magnetic Resonance Imaging for Evaluating Renal Allograft Injury

  • Yuan Meng Yu;Qian Qian Ni;Zhen Jane Wang;Meng Lin Chen;Long Jiang Zhang
    • Korean Journal of Radiology
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    • 제20권6호
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    • pp.894-908
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    • 2019
  • Kidney transplantation is the treatment of choice for patients with end-stage renal disease, as it extends survival and increases quality of life in these patients. However, chronic allograft injury continues to be a major problem, and leads to eventual graft loss. Early detection of allograft injury is essential for guiding appropriate intervention to delay or prevent irreversible damage. Several advanced MRI techniques can offer some important information regarding functional changes such as perfusion, diffusion, structural complexity, as well as oxygenation and fibrosis. This review highlights the potential of multiparametric MRI for noninvasive and comprehensive assessment of renal allograft injury.

Tube Voltage, DNA Double-Strand Breaks, and Image Quality in Coronary CT Angiography

  • Zhu Xiao Lin;Fan Zhou;U. Joseph Schoepf;Balakrishnan Pillai;Chang Sheng Zhou;Wei Quan;Xue Qin Bao;Guang Ming Lu;Long Jiang Zhang
    • Korean Journal of Radiology
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    • 제21권8호
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    • pp.967-977
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    • 2020
  • Objective: To evaluate the effects of tube voltage on image quality in coronary CT angiography (CCTA), the estimated radiation dose, and DNA double-strand breaks (DSBs) in peripheral blood lymphocytes to optimize the use of CCTA in the era of low radiation doses. Materials and Methods: This study included 240 patients who were divided into 2 groups according to the DNA DSB analysis methods, i.e., immunofluorescence microscopy and flow cytometry. Each group was subdivided into 4 subgroups: those receiving CCTA only with different tube voltages of 120, 100, 80, or 70 kVp. Objective and subjective image quality was evaluated by analysis of variance. Radiation dosages were also recorded and compared. Results: There was no significant difference in demographic characteristics between the 2 groups and 4 subgroups in each group (all p > 0.05). As tube voltage decreased, both image quality and radiation dose decreased gradually and significantly. After CCTA, γ-H2AX foci and mean fluorescence intensity in the 120-, 100-, 80-, and 70-kVp groups increased by 0.14, 0.09, 0.07, and 0.06 foci per cell and 21.26, 9.13, 8.10, and 7.13 (all p < 0.05), respectively. The increase in the DNA DSB level in the 120-kVp group was higher than those in the other 3 groups (all p < 0.05), while there was no significant difference in the DSBs levels among these latter groups (all p > 0.05). Conclusion: The 100-kVp tube voltage may be optimal for CCTA when weighing DNA DSBs against the estimated radiation dose and image quality, with further reductions in tube voltage being unnecessary for CCTA.

Terahertz (THz) imaging technology for therapeutic and diagnostic applications of cancer incorporating with radiopharmaceutical fields

  • Min, Sun-Hong;Cho, Ilsung;Park, Chawon;Jung, Wongyun;Hwang, Won Taek;Kim, Minho;Lee, Kyo Chul;Lee, Yong Jin;Lim, Sang Moo;Hong, Bong Hwan
    • 대한방사성의약품학회지
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    • 제5권2호
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    • pp.120-128
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    • 2019
  • Radiopharmaceuticals include therapeutic radiopharmaceuticals and diagnostic radiopharmaceuticals. Therapeutic radiopharmaceuticals are administered to the body and ingested at specific organs to detect radiation emitted from the site and to construct an image to diagnose the disease. Diagnostic radiopharmaceuticals are used to treat diseases by killing cells with radiation emitted from radiopharmaceuticals, such as cancer cells, vascular endothelial cells, arthritis, and Alzheimer's disease. The application possibilities of terahertz imaging technology for the combination of radiopharmaceuticals and molecular imaging medicine are discussed and experimental methods are presented. Terahertz imaging is expected to be a powerful technique because of the effective piercing feasibility, which enables to perform safe and high resolutive imaging. To investigate the response of cell to the terahertz wave, both the pulsed and CW THz wave systems are employed. THz imaging of a rat's paraffin-embedded epithelial cell with tumor is studied in advance.

Clinical Application of MRI in an Animal Bone Graft Model

  • Liu, Xiaochen;Jia, Wenxiao;Jin, Gele;Wang, Hong;Ma, Jingxu;Wang, Yunling;Yang, Yi;Deng, Wei
    • Journal of Magnetics
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    • 제18권2호
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    • pp.142-149
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    • 2013
  • We aim to monitor vascularization of early bone perfusion following rabbit lumbar intertransverse bone graft fusion surgery using magnetic resonance imaging assessment. Correlation with graft survival status was evaluated by histological method. Experimental animals were randomly divided into three groups and the model was established by operating bilateral lumbar intertransverse bone graft with different types of bone graft substitute material. The lumbar intertransverse area of three groups of rabbits was scanned via MRI. In addition, histological examinations were performed at the $6^{th}$ week after surgery and the quantitative analysis of the osteogenesis in different grafted area was carried out by an image analysis system. The MRI technique can be used for early postoperative evaluation of vascularized bone graft perfusion after transplantation of different bone materials, whereas histological examination allows direct visualization of the osteogenesis process.

Hyperpolarized Carbon-13 Magnetic Resonance Imaging: Technical Considerations and Clinical Applications

  • Ying-Chieh Lai;Ching-Yi Hsieh;Yu-Hsiang Juan;Kuan-Ying Lu;Hsien-Ju Lee;Shu-Hang Ng;Yung-Liang Wan;Gigin Lin
    • Korean Journal of Radiology
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    • 제25권5호
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    • pp.459-472
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    • 2024
  • Hyperpolarized (HP) carbon-13 (13C) MRI represents an innovative approach for noninvasive, real-time assessment of dynamic metabolic flux, with potential integration into routine clinical MRI. The use of [1-13C]pyruvate as a probe and its conversion to [1-13C]lactate constitute an extensively explored metabolic pathway. This review comprehensively outlines the establishment of HP 13C-MRI, covering multidisciplinary team collaboration, hardware prerequisites, probe preparation, hyperpolarization techniques, imaging acquisition, and data analysis. This article discusses the clinical applications of HP 13C-MRI across various anatomical domains, including the brain, heart, skeletal muscle, breast, liver, kidney, pancreas, and prostate. Each section highlights the specific applications and findings pertinent to these regions, emphasizing the potential versatility of HP 13C-MRI in diverse clinical contexts. This review serves as a comprehensive update, bridging technical aspects with clinical applications and offering insights into the ongoing advancements in HP 13C-MRI.

Current Status of Magnetic Resonance Imaging in Patients with Malignant Uterine Neoplasms: A Review

  • Yu-Ting Huang;Yen-Ling Huang;Koon-Kwan Ng;Gigin Lin
    • Korean Journal of Radiology
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    • 제20권1호
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    • pp.18-33
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    • 2019
  • In this study, we summarize the clinical role of magnetic resonance imaging (MRI) in the diagnosis of patients with malignant uterine neoplasms, including leiomyosarcoma, endometrial stromal sarcoma, adenosarcoma, uterine carcinosarcoma, and endometrial cancer, with emphasis on the challenges and disadvantages. MRI plays an essential role in patients with uterine malignancy, for the purpose of tumor detection, primary staging, and treatment planning. MRI has advanced in scope beyond the visualization of the many aspects of anatomical structures, including diffusion-weighted imaging, dynamic contrast enhancement-MRI, and magnetic resonance spectroscopy. Emerging technologies coupled with the use of artificial intelligence in MRI are expected to lead to progressive improvement in case management of malignant uterine neoplasms.