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1.发明授权Contrast enhanced MRA with highly constrained backprojection reconstruction using phase contrast composite image 有权使用相位对比合成图像对比增强MRA和高度受限的反投影重建公开(公告)号：US07991452B2
公开(公告)日：2011-08-02
申请号：US11966237
申请日：2007-12-28
IPC分类号： A61B5/055
CPC分类号： G01R33/561 , G01R33/4824 , G01R33/5601 , G01R33/56308 , G01R33/56316 , G01R33/5635 , G01R33/56509
摘要： Mask projection views are obtained prior to the arrival of a contrast agent during a dynamic contrast enhanced MRA study. After the arrival of the contrast agent, a set of undersampled contrast enhanced projection views are obtained for each of a plurality of time frames. Corresponding mask projection views are subtracted from the contrast enhanced projection views to provide sparse contrast enhanced projection view sets. A phase contrast scan of a region of interest is performed prior to or after the arrival of the contrast agent. The phase contrast image is used as a composite image in a HYPR reconstruction of the sparse projection view sets to produce first pass contrast enhanced images. Iterative HYPR reconstructions can also be performed to remove venous information from the reconstructed images.
摘要翻译： 在动态造影增强MRA研究期间，在造影剂到达之前获得掩模投影视图。 在造影剂到达之后，对于多个时间帧中的每一个获得一组欠采样的对比度增强的投影视图。 从对比度增强的投影视图中减去相应的掩模投影视图，以提供稀疏对比度增强的投影视图集。 感兴趣区域的相位扫描在造影剂到达之前或之后进行。 相位对比图像用作稀疏投影视图集的HYPR重建中的合成图像，以产生第一遍对比度增强图像。 还可以进行迭代HYPR重建以从重建的图像中去除静脉信息。
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2.发明授权Time-resolved digital subtraction magnetic resonance angiography using echo-planar imaging 失效时间分辨数字减影磁共振血管造影使用回波平面成像
公开(公告)号：US6044290A
公开(公告)日：2000-03-28
申请号：US55503
申请日：1998-04-06
IPC分类号： G01R33/54 , G01R33/561 , G01R33/563 , A61B5/055
CPC分类号： G01R33/5615 , G01R33/4822 , G01R33/5616 , G01R33/563
摘要： A dynamic MRA study of a subject is performed using a 3D echo-planar imaging pulse sequence. Four phase encoding views are acquired for each pulse repetition period (TR) and this enables higher resolution images to be acquired without a reduction of temporal frame rate or a loss of image CNR.
摘要翻译： 使用3D回波平面成像脉冲序列进行对象的动态MRA研究。 对于每个脉冲重复周期（TR）获取四个相位编码视图，这使得能够获取更高分辨率的图像，而不会降低时间帧速率或图像CNR的损失。
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3.发明授权RF coil assembly and method for practicing magnetization transfer on magnetic resonance imaging and spectroscopy systems 有权RF线圈组件和用于在磁共振成像和光谱系统上实施磁化转移的方法公开(公告)号：US07508212B2
公开(公告)日：2009-03-24
申请号：US11841201
申请日：2007-08-20
IPC分类号： G01V3/00
CPC分类号： G01R33/3635 , G01R33/345 , G01R33/3453 , G01R33/365 , G01R33/3678 , G01R33/3685 , G01R33/5601 , G01R33/5605 , G01R33/5659
摘要： An RF coil assembly for an MRI system includes a resonator formed by a cylindrical shield and pairs of opposing conductive legs disposed symmetrically around a central axis and extending the axial length of the shield. One set of conductive leg pairs is tuned to operate at the Larmor frequency of 13C and another set is tuned to operate at the Larmor frequency of 1H. Drive circuitry operates the RF coil assembly to produce 1H spin magnetization which is transferred to 13C magnetization by the nuclear overhauser effect and to acquire MR data from the 13C spins. Multinuclear measurements can be made simultaneously at different Larmor frequencies.
摘要翻译： 用于MRI系统的RF线圈组件包括由圆柱形屏蔽件形成的谐振器和成对的相对的导电腿，所述相对导电腿对称地设置在中心轴线周围并延伸屏蔽件的轴向长度。 一组导电支线对被调谐为以13C的拉莫尔频率工作，另一组被调谐以在1H的拉莫尔频率下操作。 驱动电路操作RF线圈组件以产生1H自旋磁化，其通过核超越效应转移到13C磁化并从13C旋转获取MR数据。 多核测量可以在不同的拉莫尔频率下同时进行。
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公开(公告)号：US5830143A
公开(公告)日：1998-11-03
申请号：US787181
申请日：1997-01-21
IPC分类号： G01R33/28 , A61B5/055 , G01R33/48 , G01R33/561 , G01R33/563 , G01R33/567 , H61B5/055
CPC分类号： G01R33/561 , G01R33/281 , G01R33/563 , G01R33/56308 , G01R33/567
摘要： A dynamic MRA study of a subject is performed using a 3D fast gradient-recalled echo pulse sequence that employs a non-selective RF excitation pulse. The frame rate of the resulting series of reconstructed images is increased by sampling a central region of k-space at a higher rate than the peripheral regions of k-space. The acquisition is gated using a cardiac trigger signal and the central region of k-space is acquired during diastole and the peripheral regions of k-space are acquired during systole. Image frames are reconstructed at each sampling of the central k-space region using the temporally nearest samples from the peripheral k-space regions. Two of the image frames are subtracted to form an MR angiogram.
摘要翻译： 使用采用非选择性RF激励脉冲的3D快速梯度回波脉冲序列来执行对象的动态MRA研究。 通过以比k空间的外围区域更高的速率对k空间的中心区域进行采样来增加所得到的一系列重构图像的帧速率。 使用心脏触发信号门控获取，并且在舒张期期间获取k空间的中心区域，并且在收缩期间获取k空间的周边区域。 使用来自外围k空间区域的时间上最近的采样，在中心k空间区域的每个采样处重构图像帧。 减去两个图像帧以形成MR血管造影图。
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5.发明授权Method for producing a time-resolved series of 3D magnetic resonance angiograms during the first passage of contrast agent 失效在造影剂第一次通过期间产生时间分辨系列的3D磁共振血管造影的方法
公开(公告)号：US5713358A
公开(公告)日：1998-02-03
申请号：US622718
申请日：1996-03-26
IPC分类号： G01R33/28 , A61B5/055 , G01R33/48 , G01R33/54 , G01R33/561 , G01R33/563
CPC分类号： G01R33/5619 , G01R33/5635 , G01R33/56325
摘要： A dynamic MRA study of a subject is performed using a 3D fast gradient-recalled echo pulse sequence. The frame rate of the resulting series of reconstructed images is increased by sampling a central region of k-space at a higher rate than the peripheral regions of k-space. Image frames are reconstructed at each sampling of the central k-space region using the temporally nearest samples from the peripheral k-space regions.
摘要翻译： 使用3D快速梯度回波脉冲序列进行受试者的动态MRA研究。 通过以比k空间的外围区域更高的速率对k空间的中心区域进行采样来增加所得到的一系列重构图像的帧速率。 使用来自外围k空间区域的时间上最近的采样，在中心k空间区域的每个采样处重构图像帧。
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6.发明授权公开(公告)号：US07714581B2
公开(公告)日：2010-05-11
申请号：US11726643
申请日：2007-03-22
IPC分类号： G01V3/00
CPC分类号： G01R33/345 , G01R33/3453 , G01R33/3635 , G01R33/365 , G01R33/3678 , G01R33/3685 , G01R33/422 , G01R33/5659
摘要： An RF coil assembly for an MRI system includes a resonator formed by a cylindrical shield and pairs of opposing conductive legs disposed symmetrically around a central axis and extending the axial length of the shield. Drive circuitry for each pair of opposing conductive legs includes a current balun that maintains substantially equal and opposite currents in the two conductive legs. Terminal susceptance elements are used to maintain maximum currents and minimum voltage at the midpoints of the conductive legs. Multinuclear measurements can be made simultaneously at different Larmor frequencies.
摘要翻译： 用于MRI系统的RF线圈组件包括由圆柱形屏蔽件形成的谐振器和成对的相对的导电腿，所述相对导电腿对称地设置在中心轴线周围并延伸屏蔽件的轴向长度。 每对相对导电支腿的驱动电路包括一个电流平衡 - 不平衡变换器，它们在两个导电支路中保持基本上相等和相反的电流。 终端电纳元件用于在导电腿的中点处保持最大电流和最小电压。 多核测量可以在不同的拉莫尔频率下同时进行。
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7.发明授权公开(公告)号：US07146282B1
公开(公告)日：2006-12-05
申请号：US11124599
申请日：2005-05-06
CPC分类号： G01R33/5604 , G01R31/2829 , G01R33/323
摘要： Localized magnetic fields are measured at frequencies into the microwave (GHz) regime using a conductive loop that is integrated on a vibratable member, such as a cantilever. Driving an alternating current at a first high frequency through the loop produces a high frequency alternating magnetic dipole at the same frequency as the current, with the alternating magnetic dipole normal to and centered within the loop. The alternating magnetic dipole at the center of the loop mixes with a sampled alternating magnetic field at a second high frequency at the center of the loop, resulting in application of a mechanical force to the loop and vibratable member. The vibratable member vibrates when the difference between the frequency of the loop current and the frequency of the sampled alternating magnetic field equals the resonant frequency of the vibratable member.
摘要翻译： 使用集成在可振动构件（例如悬臂）上的导电回路，将频率测量到微波（GHz）状态下的局部磁场。 通过环路以第一高频驱动交流电流产生与电流相同频率的高频交变磁偶极子，其中交变磁偶极子垂直于环路并居中。 环路中心处的交变磁偶极子与循环中心处的第二高频处的采样交变磁场混合，从而对环路和可振动构件施加机械力。 当环路电流的频率和采样的交变磁场的频率之间的差值等于可振动部件的共振频率时，可振动部件振动。
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公开(公告)号：US06794867B1
公开(公告)日：2004-09-21
申请号：US10461227
申请日：2003-06-13
申请人： Walter F. Block , Thomas M. Grist , Aiming Lu
发明人： Walter F. Block , Thomas M. Grist , Aiming Lu
IPC分类号： G01V300
CPC分类号： G01R33/4828 , G01R33/5613
摘要： Two images are acquired using a three-dimensional projection reconstruction, SSFP pulse sequence. Different RF phase cycling patterns are used to acquire each image and a fat suppressed water image is produced by combining the two images. Data acquisition efficiency is increased by aquiring k-space data during substantially the entire readout gradient waveform produced during the SSFP pulse sequence.
摘要翻译： 使用三维投影重建，SSFP脉冲序列获取两个图像。 使用不同的RF相位循环模式来获取每个图像，并且通过组合两个图像来产生脂肪抑制水图像。 通过在基本上在SSFP脉冲序列期间产生的整个读出梯度波形期间获取k空间数据来增加数据采集效率。
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公开(公告)号：US06381486B1
公开(公告)日：2002-04-30
申请号：US09314227
申请日：1999-05-18
IPC分类号： A61B505
CPC分类号： G01R33/5635 , G01R33/5619
摘要： A magnetic resonance angiogram (MRA) is acquired using a contrast enhancement method in which a series of low resolution NMR images are rapidly acquired during a time resolved phase of the examination in which the contrast bolus makes a first pass through the arteries and veins. Additional, high resolution NMR image data is acquired in a subsequent steady-state phase of the examination from which a high resolution NMR image is reconstructed. Segmentation of arteries, veins and background in the high resolution image is performed using information in the low resolution NMR images.
摘要翻译： 使用对比度增强方法获得磁共振血管造影（MRA），其中在检查的时间分辨阶段期间快速获取一系列低分辨NMR图像，其中对比剂推注首先通过动脉和静脉。 另外，高分辨率NMR图像数据在随后的重建的高分辨率NMR图像的检查的稳态阶段获得。 使用低分辨率NMR图像中的信息来执行高分辨率图像中的动脉，静脉和背景的分割。
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公开(公告)号：US08112145B2
公开(公告)日：2012-02-07
申请号：US10860210
申请日：2004-06-03
申请人： Thomas M. Grist , Orhan Unal
发明人： Thomas M. Grist , Orhan Unal
IPC分类号： A61B5/05
CPC分类号： G01R33/5673 , G01R33/281
摘要： An assessment of myocardial viability in a subject is performed by acquiring an MR image which distinguishes infarcted myocardium from normal myocardium. A contrast agent is used and after a waiting period, a cardiac-gated segmented inversion recovery gradient-recalled radial sampling technique is employed to acquire NMR data over a substantial portion of the cardiac cycle. By interleaving the radial sampling patterns, images can be reconstructed over a range of possible TI intervals enabling the optimal TI for maximum contrast to be retrospectively selected.
摘要翻译： 通过获取将梗塞的心肌与正常心肌区分开的MR图像来进行受试者心肌存活力的评估。 使用造影剂，并且在等待期之后，使用心脏门控分段反转恢复梯度回收的径向采样技术在心脏周期的大部分时间上获取NMR数据。 通过交织径向采样图案，可以在可能的TI间隔的范围内重建图像，使得能够追溯地选择用于最大对比度的最佳TI。
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