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1.发明授权Three dimensional digital subtraction magnetic resonance angiography with limited k-space mask 失效具有有限k空间掩模的三维数字减影磁共振血管造影
公开(公告)号：US5873825A
公开(公告)日：1999-02-23
申请号：US55501
申请日：1998-04-06
IPC分类号： A61B5/055 , G01R33/54 , G01R33/563
CPC分类号： A61B5/055 , G01R33/563 , G01R33/4822
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. A difference image is produced by subtracting a mask formed by central region k-space sampling from a selected image frame formed by central region and peripheral regions k-space sampling.
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。 通过从由中央区域和外围区域k空间采样形成的所选图像帧中减去由中心区域k空间采样形成的掩模来产生差异图像。
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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
公开(公告)号：US5285158A
公开(公告)日：1994-02-08
申请号：US926658
申请日：1992-08-06
IPC分类号： A61B5/055 , G01R33/48 , G01R33/563 , G01R33/70
CPC分类号： G01R33/563
摘要： An angiogram is produced using NMR fast pulse sequences in which the views are acquired in shots preceded by a preparatory pulse sequence. Each shot is acquired twice with differing preparatory pulse sequences and the resulting NMR data is subtracted to null the stationary tissues in the reconstructed image.
摘要翻译： 使用NMR快速脉冲序列产生血管造影图像，其中在预备脉冲序列之前的拍摄中获取视图。 每个镜头用不同的准备脉冲序列获得两次，并且所得到的NMR数据被减去以使重建图像中的静止组织无效。
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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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公开(公告)号：US5204627A
公开(公告)日：1993-04-20
申请号：US669143
申请日：1991-03-14
IPC分类号： G01R33/56 , G01R33/563
CPC分类号： G01R33/563 , G01R33/56
摘要： A magnetic resonance angiogram is produced by projecting a 3D array of motion sensitized NMR data. A mask which locates the vessels in the 3D array is produced by thresholding the NMR data, and this mask is combined with the 3D NMR data set to exclude signals produced by surrounding stationary tissues. An integration projection technique is used to produce the angiogram from the masked data set.
摘要翻译： 通过投影运动敏化NMR数据的3D阵列产生磁共振血管造影。 通过对NMR数据进行阈值产生定位3D阵列中的血管的掩模，并将该掩模与3D NMR数据组合以排除由周围的静止组织产生的信号。 使用积分投影技术从掩蔽的数据集中产生血管造影。
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公开(公告)号：US5031624A
公开(公告)日：1991-07-16
申请号：US568938
申请日：1990-08-17
IPC分类号： A61B5/055 , G01R33/48 , G01R33/563 , G01R33/567
CPC分类号： G01R33/56316 , G01R33/5673
摘要： An NMR angiogram is produced using a line scan data acquisition. Each line of NMR data is acquired twice, once with a velocity sensitizing gradient having a positive first moment and once with a velocity sensitizing gradient having a negative first moment. The two signals from the acquisition are subtracted to cancel signals from stationary spins while enhancing signals from flowing spins. The magnitude of the velocity sensitizing gradient moment is changed during the cardiac cycle so that aliasing does not occur at high blood velocities and the signal strength does not drop too low at low blood velocities. An angiogram is produced by reconstructing an image from line scan data acquired from a series of slices.
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