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A novel method for evaluating and improving the 1H-MRSI glioma data quality

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Progress in Natural Science:Materials International 2005年第8期15卷 765-768页

作者： YUAN Kehong 1,2. LU Hongyu2. BAO Shanglian2., CHEN Qiansheng1, LI Shaowu3.and DUAN Chaijie2.1. key laboratory of Pure and Applied Mathematics, School of Mathematical Sciences,{2., China 2. the research center for tumor diagnosis and therapeutical physics & the beijing key laboratory of medical physics and engineering, peking university,{2., China 3. The Tian Tan Hospital, beijing 100050, China) key laboratory of Pure and Applied Mathematics School of Mathematical Sciences Beijing 100871 China. The research center for {2.{3. and therapeutical physics & the beijing key laboratory of medical physics and engineering Peking University Beijing 100871 China. The Tian Tan Hospital Beijing 100050 China

Metabolic information obtained by proton magnetic resonance spectroscopic imaging (1H-MRSI) has been approved to be a powerful tool to identify either benign or malignant glioma, as well as to confirm the tumor level. However, 1H-MRSI data are affected by various factors, such as the thermal noise, eddy currents, susceptibility artifacts, and rigid body motion. To get accurate quantitative metabolic information, the key problem is to assess the 1H-MRSI data quality. In this paper, we introduce a new evaluating system to filter the data, and a new method, called wavelet denoising method, to improve the data quality under the evaluating system. Experimental results on 1H-MRSI glioma data demonstrate that preprocessing is prerequisite and the proposed algorithm with evaluating system is effective.

关键词： 1H-MRSI evaluating system glioma data quality wavelet denoising

Parallel imaging methods for phased array MRI

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Progress in Natural Science:Materials International 2003年第4期 69-72页

作者： ZHANG Bida, WANG Weidong, SONG Xiaoyu, ZU Donglin, CHEN Guangfei and BAO Shanglian (1. Institute of Heavy Ion physics, the research {2. for{3. diagnosis and therapeutical physics, the beijing key laboratory of medical physics & {12.,{13., beijing 100871, China 2. General Hospital of PLA, beijing 100085, China) Institute of Heavy Ion physics，the research {2. for{3. diagnosis and therapeutical physics，the beijing key laboratory of medical physics & {12.，{13. university，beijing 100871，China Institute of Heavy Ion physics，the research {2. for{3. diagnosis and therapeutical physics，the beijing key laboratory of medical physics & {12.，{13. university，beijing 100871，China General Hospital of PLA，beijing 100085，China

Two parallel methods for magnetic resonance tmaging (MRI) using radio frequency (RF) phased array surface coiks, named spatial loca! Fourier encoding (SLFE) and spatial RF encoding (SRFE), are presented. The MR signals are acquired from separate channels across the coils, each of which covers a sub-FOV (field-of-view) in a parallel fashion, and the acquired data are combined to form an image of entire FOV. These two parallel encoding techniques can accelerate MR imaging greatly, yet associated artifact rnay appear, al-though the SLFE is an effective image reconstruction method which can reduce the localized artifact in some degrees. By the SRFE, RF coil array can be utilized for spatial encoding through a specialized coil design. The images are acquired in a snapshot with a high signal-to-noise ratio (SNR) without the costly gradient system, resulting in great saving of cost. Both mutual induction and aliasing effect of adja-cent coils are critical to the success of SRFE. The strategies of inverse sourc

关键词： MRI radiofrequency phased-array.

diagnosis of prostate cancer by quantitative analysis of 3.MRSI data: A new model

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Progress in Natural Science:Materials International 2005年第4期 33-37页

作者： QUAN Hong 1, WANG Xiaoying 2. BAO Shanglian 1*, WANG Huiliang 1, LI Feiyu 2.and HUANG Rong 2.1. The {3. center for {2. {3. and therapeutical physics and the beijing key laboratory of medical physics and engineering,{12., beijing 100871, China 2. Department of Radiology, The First Affiliated Hospital,{12., beijing 10003., China) The research center for {2.{3. and therapeutical physics and the beijing key laboratory of medical physics and engineering Peking University Beijing 100871 China Department of Radiology The First Affiliated Hospital Peking University Beijing 100034 China

Three dimensional magnetic resonance spectroscopic imaging (3.MRSI) is helpful to identify prostate cancer (PC) from benign prostate hyperplasia (BPH) and to show the distribution of tumor infiltration. Combined with the (Cho+Cre)/Cit ratio, the z score model can effectively discriminate prostate cancer from stromal benign prostate hyperplasia (sBPH) and detect small malignant lesions (SML).

关键词： three-dimensional magnetic resonance spectroscopic imaging (3.MRSI) prostate cancer z-score model.

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医学影像物理学科的现状和未来

物理 2004年第10期33卷 753-758页

作者：张仕刚谢耀钦包尚联北京大学肿瘤物理诊疗技术研究中心

医学影像物理学是医学物理学的重要分支 .该专业的主要目标是培养研发高精密医学影像设备的骨干和医疗机构内的医学物理师 ,以及发展该学科专业的科研和教学人才 .建立医学物理学科 ,发展医学影像物理专业是我国计划于 2.0 2.0年成为世... 详细信息

医学影像物理学是医学物理学的重要分支 .该专业的主要目标是培养研发高精密医学影像设备的骨干和医疗机构内的医学物理师 ,以及发展该学科专业的科研和教学人才 .建立医学物理学科 ,发展医学影像物理专业是我国计划于 2.0 2.0年成为世界制造业和软件业大国的重要内容之一 .中国目前还没有建立医学物理学科 ,在研发水平、教学和培训水平以及产业的规模上都还非常小 ,国家必须采取重大决策才能加速这个领域的发展 .为了赶上发达国家在这个领域的发展水平 ,进而成为世界医学影像设备的制造大国 ,最紧迫的问题之一是建立中国的医学物理学科和医学物理师制度 .文章在综述医学影像学科发展的同时 ,分析了该学科今后发展的社会需求和发展前景。

关键词：中国发展世界制造业制造大国软件业制度产业医学物理学医学影像物理学世界医学

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计算信号流图传递函数的改进算法及可视化

系统仿真学报 2003年第1期15卷 8-12页

作者：吕红宇吴重光包尚联北京大学重离子物理研究所肿瘤物理诊疗技术研究中心和北京市重点实验室:医学物理和工程北京100871 北京化工大学信息科学与技术学院北京100029

介绍了基于Shannon-Happ公式计算系统信号流图传递函数的改进算法。与Mason公式法比较,此方法简化了算法设计。首先对信号流图的一些特殊形式进行了分析,给出了一种使用回路添加技术建立互不接触回路组合的实现手段。采用分离变量的方... 详细信息

介绍了基于Shannon-Happ公式计算系统信号流图传递函数的改进算法。与Mason公式法比较,此方法简化了算法设计。首先对信号流图的一些特殊形式进行了分析,给出了一种使用回路添加技术建立互不接触回路组合的实现手段。采用分离变量的方法将符号变量引入到信号流图中, 使得求取的传递函数中可包含代表支路参数、非线性项或相对独立子系统的符号变量, 由此可直接处理系统中的非线性时间延迟项。随后探讨了将含符号变量的信号流图应用于非零状态MIMO系统的问题。简介了基于常参数网络拓扑算法的可视化和利用所得传递函数进行系统性能分析的方法, 及其仿真软件AVANT。最后文章给出了改进算法和可视化方法的检验结果。

关键词：计算信号流图传递函数可视化公式网络拓扑算法系统仿真 Shannon-Happ公式符号变量

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