搜索结果: 1-15 共查到“生物医学工程 MRI”相关记录33条 . 查询时间(0.156 秒)
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中国科学院苏州生物医学工程技术研究所杨晓冬课题组在乳腺磁共振成像(MRI)的病灶良恶性诊断技术中取得重要进展
中国科学院苏州生物医学工程技术研究所 杨晓冬 乳腺磁共振成像 MRI 病灶良恶性诊断技术
2020/9/3
乳腺癌是女性癌症中发病率和死亡率都稳居首位的恶性肿瘤。早期诊断和及时治疗有利于改善患者的预后。在常用的影像学筛查手段中,磁共振成像(MRI)具有无创无辐射、多病灶敏感、信息丰富及不受乳腺密度影响等优点。不同序列的MRI能从不同的角度提供多维度的丰富信息,进而让医生能更准确地诊断。通常在不同序列中,对应参数图的强度数值和病灶的发生、发展以及转移均息息相关。如动态增强序列(DCE-MRI)中,其参数图...
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北京大学工学院生物医学工程系段小洁课题组及合作者在MRI兼容神经电极及DBS-fMRI联用揭示DBS对大脑调制效应方面取得重要进展(图)
北京大学工学院 生物医学工程 段小洁 MRI兼容神经电极 DBS-fMRI DBS 大脑调制效应
2020/4/16
近日,北京大学工学院生物医学工程系段小洁研究员课题组与中国科学院神经科学研究所、脑科学与智能技术卓越创新中心梁智锋课题组合作,研制了一种基于石墨烯纤维的高度兼容MRI的DBS刺激电极,在帕金森症大鼠模型上,实现了DBS下整脑范围内完整fMRI脑激活图谱的扫描,发现了DBS治疗帕金森症效果与不同脑区激活的关联关系。该石墨烯纤维DBS电极具有高于同尺寸铂铱(PtIr,临床DBS所用的材料)电极70倍的...
Metal-free MRI contrast agent could be safer for some patients
Metal-free MRI contrast agent safer for some patients
2017/7/24
To enhance the visibility of organs as they are scanned with magnetic resonance imaging (MRI), patients are usually injected with a compound known as a contrast agent before going into the scanner. Th...
研制用于鼻咽癌放射治疗定位的CT/MRI图像配准辅助装置,并且通过组织勾画差异分析使用该装置后所得配准融合图像在临床中的应用意义。方法 在普通的磁共振头颈线圈中设计特定形状的头枕,保持患者在扫描时与CT定位扫描时相同的体位。采用配对t检验分析CT图像与融合图像中腮腺、下颌骨的勾画差异。结果 患者的头颈部CT、MRI图像的配准精度较未使用该装置的图像具有明显的提高,使用该配准图像得到的融合图像、组织...
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二型糖尿病是一种常见的以高血糖为特征的代谢疾病,其对大脑的影响主要表现在神经反应速度的减慢和思维灵活度的减弱。研究表明,由于胰岛素耐受性和患者血糖水平等因素会引起脑部的认知损伤,糖尿病不仅会加速认知功能的退化同时也会增加患者得阿兹海默病(老年痴呆)的风险。脑部胰岛素受体表达的减弱会阻碍胰岛素信号的传递,同时,脑脊液中的胰岛素水平也会对认知功能产生影响。临床研究发现,患有糖尿病的患者更容易患阿兹海默...
乳腺DCE-MRI增强场时间序列和组织形变场的联合估计
乳腺肿瘤 动态增强磁共振 图像配准 马尔科夫随机场
2017/1/12
乳腺DCE-MRI扫描过程中,病人运动等会使图像序列产生运动伪影,需要对DCE-MRI时间序列图像进行运动补偿,消除运动伪影的影响.为充分利用数据信息和增强在空间和时间上的先验信息,本文提出了联合估计增强场时间序列和组织形变场的贝叶斯框架.采用离散马尔科夫随机场模型分别对增强场时间序列和组织形变场进行建模和添加平滑约束,并通过分步迭代方式进行估计.利用估计的增强场对DCE-MRI时间序列图像进行“...
一种基于分段迭代的MRI成像涡流补偿方法
梯度电流 涡流补偿 累积误差 分段迭代计算
2014/10/17
在核磁共振成像中,涡流的存在会影响系统的成像质量。梯度电流预增强方法是一种被广泛采用的有效的涡流补偿方法。梯度电流预增强在一个周期内要进行上千次e指数计算,需采用快速的计算方法。迭代计算是普遍采用的涡流补偿快速计算方法,但是存在累积误差放大的问题。针对这种问题,基于迭代计算原理,我们提出了一种改进的分段迭代的MRI成像涡流补偿计算方法。实验结果表明,在计算时间同量级的条件下有效地提高了梯度预增强量...
Comprehensive approach for motion and distortion correction in diffusion weighted MRI
Comprehensive approach motion and distortion correction diffusion weighted MRI
2009/12/23
Comprehensive approach for motion and distortion correction in diffusion weighted MRI.
Estimating intensity variance due to noise in registered images: applications to DT-MRI
intensity variance noise registered images DT-MRI
2009/12/23
Estimating intensity variance due to noise in registered images: applications to DT-MRI.
Brain Structure Segmentation from MRI by Geometric Surface Flow
Brain Structure Segmentation MRI
2009/9/8
We present a method for semiautomatic segmentation of brain structures such as thalamus from MRI images based on the concept of geometric surface flow. Given an MRI image, the user can interactively i...
Optimization of Spiral MRI Using a Perceptual Difference Model
MRI Perceptual Difference Model
2009/9/8
We systematically evaluated a variety of MR spiral imaging acquisition and reconstruction schemes using a computational perceptual difference model (PDM) that models the ability of humans to perceive ...
Reciprocal Benefits of Mass-Univariate and Multivariate Modeling in Brain Mapping: Applications to Event-Related Functional MRI, H215O-, and FDG-PET
MRI H215O FDG-PET
2009/9/8
In brain mapping studies of sensory, cognitive, and motor operations, specific waveforms of dynamic neural activity are predicted based on theoretical models of human information processing. For examp...
Improving Non-Cartesian MRI Reconstruction through Discontinuity Subtraction
Non-Cartesian MRI Discontinuity Subtraction
2009/9/8
Non-Cartesian sampling is widely used for fast magnetic resonance imaging (MRI). Accurate and fast image reconstruction from non-Cartesian k-space data becomes a challenge and gains a lot of attention...
A Note on the Iterative MRI Reconstruction from Nonuniform k-Space Data
the Iterative MRI Nonuniform k-Space Data
2009/9/7
In magnetic resonance imaging (MRI), methods that use a non-Cartesian grid in k-space are becoming increasingly important. In this paper, we use a recently proposed implicit discretisation scheme whic...
Registration of Brain MRI/PET Images Based on Adaptive Combination of Intensity and Gradient Field Mutual Information
MRI/PET Images Intensity
2009/9/7
Traditional mutual information (MI) function aligns two multimodality images with intensity information, lacking spatial information, so that it usually presents many local maxima that can lead to ina...