公开(公告)号：US06317620B1

公开(公告)日：2001-11-13

申请号：US09565978

申请日：2000-05-04

申请人： Vincent B. Ho ,  Thomas K. F. Foo

发明人： Vincent B. Ho ,  Thomas K. F. Foo

IPC分类号： A61B5055

CPC分类号： G01R33/56308 ,  G01R33/56316

摘要： A method and apparatus is disclosed to rapidly assess the severity of a stenosis using MR technology. The invention includes identifying a suspected stenotic vessel and applying a phase contrast pulse sequence to the stenotic vessel in which the MR operator is allowed to control the amplitude and direction of the flow encoding gradient. Peak flow velocity is determined in the suspected stenotic vessel by correlating the flow encoding gradient with the onset of flow velocity aliasing. In a preferred embodiment, the invention utilizes a 2D fast gradient echo pulse sequence having flow sensitizing bipolar gradient waveforms. The resulting flow sensitizing gradients are substantially coincident in time, thereby allowing rotation of the resultant flow sensitizing gradient direction. The amplitude of the flow encoding gradient is increased until the observance of flow related aliasing. Once flow related aliasing is observed, the velocity encoding (VENC) value is recorded and used as the indicator of peak flow velocity in the suspected stenotic vessel. The process can be repeated along the suspected stenosis vessel to isolate and assess the severity of the stenosis by comparing the peak flow velocity VENC values obtained at various locations along the suspected stenosis.

摘要翻译： 公开了一种使用MR技术快速评估狭窄严重程度的方法和装置。 本发明包括识别怀疑的狭窄血管并将相位对比脉冲序列应用于允许MR操作者控制流动编码梯度的幅度和方向的狭窄血管。 通过将流动编码梯度与流速混叠的开始相关联，在疑似狭窄的血管中确定峰值流速。 在优选实施例中，本发明利用具有流敏增强双极梯度波形的2D快速梯度回波脉冲序列。 所得到的流动敏化梯度在时间上基本一致，从而允许所得到的流动增感梯度方向旋转。 流编码梯度的幅度增加，直到遵循流相关混叠。 一旦观察到流相关的混叠，记录速度编码（VENC）值，并将其用作疑似狭窄血管中峰值流速的指标。 可以沿着疑似狭窄血管重复该过程，以通过比较沿着可疑狭窄处在不同位置处获得的峰值流速VENC值来分离和评估狭窄的严重性。

公开(公告)号：US07738944B2

公开(公告)日：2010-06-15

申请号：US10907883

申请日：2005-04-19

申请人： Vincent B. Ho ,  Thomas K. F. Foo

发明人： Vincent B. Ho ,  Thomas K. F. Foo

IPC分类号： A61B5/05

CPC分类号： G01R33/56375 ,  A61B5/0555 ,  G06F19/00

摘要： The present invention includes a method and apparatus for high sensitivity whole body scanning using MR imaging. The invention includes acquiring MR data as the patient moves through the iso-center of the magnet while providing interactive control for the operator to change scan parameters and table motion and direction. The technique allows efficient whole body scanning for fast screening of abnormalities while allowing operator control during the screening process to interrupt table motion and redirect the speed and direction of the table while also allowing control over the acquisition plane, number of sections imaged, inter-section spacing, and the scan location.

摘要翻译： 本发明包括使用MR成像进行高灵敏度全身扫描的方法和装置。 本发明包括当患者移动通过磁体的等中心时获取MR数据，同时为操作者提供交互式控制以改变扫描参数和表格运动和方向。 该技术允许有效的全身扫描快速筛选异常，同时允许操作者在筛选过程中控制中断台面运动并重定向表的速度和方向，同时还允许控制采集平面，成像部分数量，间隔 间距和扫描位置。

公开(公告)号：US06580937B2

公开(公告)日：2003-06-17

申请号：US09681092

申请日：2000-12-30

申请人： Vincent B. Ho ,  Thomas K. F. Foo

发明人： Vincent B. Ho ,  Thomas K. F. Foo

IPC分类号： A61B505

CPC分类号： G01R33/56375 ,  G01R33/281 ,  G01R33/5619

摘要： A method and apparatus are disclosed for creating peripheral MR angiographic images and performing an MRA examination using an intravascular contrast agent in which MR data acquisition is optimized in the most distal stations in a multi-station acquisition. The technique includes administering a contrast agent into the blood stream of the patient, acquiring low spatial resolution MR images of the arterial vasculature, and tracking the passage of the contrast agent through the patient. The patient table is moved in response to the tracking. The technique continues to acquire low spatial resolution images at each of the proximal stations until the most distal station is reached where a high spatial resolution image data set is then acquired of preferentially arterial vascular structures. Higher spatial resolution images are then acquired in the proximal stations.

摘要翻译： 公开了一种用于创建外周MR血管造影图像并使用血管内造影剂进行MRA检查的方法和装置，其中在多站采集中在多数远端站中优化MR数据采集。 该技术包括将造影剂施用到患者的血液流中，获取动脉脉管系统的低空间分辨率MR图像，以及跟踪造影剂通过患者的通过。 响应于跟踪，移动患者台。 该技术继续获得每个近端站处的低空间分辨率图像，直到达到最远端站点，然后获得优先动脉血管结构的高空间分辨率图像数据集。 然后在近端站获得较高的空间分辨率图像。

公开(公告)号：US06493569B2

公开(公告)日：2002-12-10

申请号：US09681090

申请日：2000-12-30

申请人： Thomas K. F. Foo ,  Vincent B. Ho

发明人： Thomas K. F. Foo ,  Vincent B. Ho

IPC分类号： A61B505

CPC分类号： G01R33/5601 ,  G01R33/5613

摘要： A system and method are disclosed that use the steady-state free precessing (SSFP) technique for MR imaging to allow the acquisition of MR angiography images in which the acquisition is not time dependent upon the first passage of a contrast agent. The technique includes applying a pulse sequence with refocusing S− signals from a train of RF pulses to a desired field-of-view (FOV) in a patient in which a contrast bolus has been injected. An SSFP image of the desired FOV is acquired, together with an S− SSFP mask image of the desired FOV. The S− SSFP mask image is subtracted from the SSFP image in order to reconstruct an image with improved visualization of the arterial and venous structures and reduce mis-registration artifacts.

摘要翻译： 公开了一种系统和方法，其使用用于MR成像的稳态自由进动（SSFP）技术来允许获取MR血管造影图像，其中采集不依赖于造影剂的第一次通过时间。 该技术包括在已经注射造影剂的患者中施加具有来自RF脉冲串的重聚合S-信号到脉冲期望视场（FOV）的脉冲序列。 获取所需FOV的SSFP图像以及所需FOV的S- SSFP掩模图像。 从SSFP图像中减去S- SSFP掩模图像，以便重建具有改善的动脉和静脉结构可视化的图像并减少误配对伪影。

公开(公告)号：US06192264B1

公开(公告)日：2001-02-20

申请号：US09221500

申请日：1998-12-28

申请人： Thomas K. F. Foo ,  Vincent B. Ho ,  Steven D. Wolff

发明人： Thomas K. F. Foo ,  Vincent B. Ho ,  Steven D. Wolff

IPC分类号： A61B5055

CPC分类号： A61B5/055 ,  A61B5/0037

摘要： A system and method for arterial and venous discrimination in MR venography is disclosed. By setting a noise level in the phase image (that is proportional to the velocity encoding value) at a threshold level between that of the arterial signals and the venous signals during the diastole portion of the cardiac cycle and acquiring a phase contrast MR image during the diastole portion, the arterial signals are effectively suppressed and a venous only image can be reconstructed. Post-processing steps are disclosed which can alternatively provide an arterial only image. By separately reconstructing a magnitude image and a phase image map to produce a magnitude image and a phase image, a masking module can create an output displaying venous only or arterial only images based on a user selection. The present invention allows for a complete noninvasive angiography exam to be completed within approximately 30 minutes.

摘要翻译： 公开了MR静脉造影中的动脉和静脉鉴别的系统和方法。 通过在心动周期的舒张期期间将相位图像中的噪声电平（与速度编码值成比例）设置在动脉信号与静脉信号之间的阈值水平，并在心脏周期的舒张期期间获取相位对比MR图像 舒张部分，有效地抑制动脉信号，并且可以重建仅静脉图像。 公开了后处理步骤，其可以替代地提供仅动脉图像。 通过分别重建幅度图像和相位图像映射以产生幅度图像和相位图像，掩蔽模块可以基于用户选择创建仅显示静脉或仅主动图像的输出。 本发明允许在大约30分钟内完成完整的非侵入性血管造影检查。

公开(公告)号：US6135954A

公开(公告)日：2000-10-24

申请号：US118411

申请日：1998-07-17

申请人： Thomas K. F. Foo ,  Vincent B. Ho ,  Matthew A. Bernstein

发明人： Thomas K. F. Foo ,  Vincent B. Ho ,  Matthew A. Bernstein

摘要： A method of peripheral MR angiography is provided for imaging an artery or other vessel, wherein the vessel is of such length that MR data must be acquired at each of a plurality of scan stations spaced along the vessel. In accordance with the method, a contrast agent is intravenously injected, in order to provide a bolus which successively flows to each of the scan stations. After acquiring an initial subset of the MR data associated with a given scan station, the bolus is tracked to determine whether it has arrived at the next-following scan station. If so, at least some of the MR data associated with the next scan station are then acquired. However, if it is found that the bolus has not yet arrived at the next scan station, acquisition of further data at the given scan station is continued.

公开(公告)号：US06246897B1

公开(公告)日：2001-06-12

申请号：US09210334

申请日：1998-12-11

申请人： Thomas K. F. Foo ,  Vincent B. Ho

发明人： Thomas K. F. Foo ,  Vincent B. Ho

IPC分类号： A61B500

CPC分类号： G01R33/5635 ,  G01R33/56316

摘要： A system and method for the acquisition of preferential arterial and venous images is disclosed. The invention includes setting a noise level in the phase image, that is proportional to the velocity encoding value, at a threshold level above the venous signal but below the arterial signal during a systolic portion of the cardiac cycle and acquiring a phase contrast MR image during the systolic portion that effectively acquires the arterial signal and suppresses the venous signal. During the diastolic portion of the same R—R interval, the velocity encoding value is then set to establish a noise threshold level in the phase image lower to a value below the venous signal but above the arterial signal to acquire the venous signal and suppress the arterial signal. In this manner, either an arterial only image or a venous only image can be displayed. Alternatively, the images can be combined to create a higher SNR arterial and venous image.

摘要翻译： 公开了一种用于获取优先动脉和静脉图像的系统和方法。 本发明包括在心脏周期的收缩期内在静脉信号以上的阈值水平处设定与速度编码值成比例的相位图像中的噪声水平，并且在心动周期的收缩期部分中获取相位对比度MR图像 收缩部分有效获取动脉信号并抑制静脉信号。 在相同RR间期的舒张部分期间，速度编码值被设置为在相位图像中建立低于静脉信号但低于动脉信号的值的噪声阈值电平，以获取静脉信号并抑制动脉信号 。 以这种方式，可以显示仅动脉图像或仅静脉图像。 或者，可以组合图像以产生更高SNR的动脉和静脉图像。

公开(公告)号：US08165377B2

公开(公告)日：2012-04-24

申请号：US12323594

申请日：2008-11-26

申请人： Vivek Vaidya ,  Rakesh Mullick ,  Shekhar Dwivedi ,  Thomas K. F. Foo ,  Christopher Judson Hardy ,  Daniel James Blezek ,  Umesha Perdoor Srinivas Adiga

发明人： Vivek Vaidya ,  Rakesh Mullick ,  Shekhar Dwivedi ,  Thomas K. F. Foo ,  Christopher Judson Hardy ,  Daniel James Blezek ,  Umesha Perdoor Srinivas Adiga

IPC分类号： G06K9/00 ,  A61B5/05

CPC分类号： A61B5/055 ,  A61B5/0037 ,  A61B6/032 ,  A61B6/503 ,  A61B8/14 ,  G06T7/75 ,  G06T2207/10088 ,  G06T2207/30048

摘要： An apparatus, system and method to determine a coordinate system of a heart includes an imager and a computer. The computer is programmed to acquire a first set of initialization imaging data from an anatomical region of a free-breathing subject. A portion of the first set of initialization imaging data includes organ data, which includes cardiac data. The computer is further programmed to determine a location of a central region of a left ventricle of a heart, where the location is based on the organ data and a priori information. The computer is also programmed to determine a short axis of the left ventricle based on the determined location, acquire a first set of post-initialization imaging data from the free-breathing subject from an imaging plane orientation based on the determination of the short axis, and reconstruct at least one image from the first set of post-initialization imaging data.

摘要翻译： 用于确定心脏坐标系的装置，系统和方法包括成像器和计算机。 计算机被编程为从自由呼吸对象的解剖区域获取第一组初始化成像数据。 第一组初始化成像数据的一部分包括包括心脏数据的器官数据。 计算机还被编程为确定心脏左心室的中心区域的位置，其中位置基于器官数据和先验信息。 计算机还被编程为基于确定的位置来确定左心室的短轴，基于短轴的确定，从成像平面取向获取来自自由呼吸对象的第一组初始初始化后成像数据， 并且从所述第一组初始化后成像数据重建至少一个图像。

公开(公告)号：US06618605B1

公开(公告)日：2003-09-09

申请号：US09391965

申请日：1999-09-08

申请人： Steven D. Wolff ,  Glenn S. Slavin ,  Thomas K. F. Foo

发明人： Steven D. Wolff ,  Glenn S. Slavin ,  Thomas K. F. Foo

IPC分类号： A61B5055

CPC分类号： G01R33/56341 ,  G01R33/4838

摘要： A method and apparatus is disclosed for MR perfusion acquisition using a notched RF saturation pulse. In acquiring such MR data, a volume of slice locations is selected in which MR data is to be acquired. Each given slice is prepared with a notched RF saturation pulse which has a stop-band between a pair of pass-bands. The stop-band is designed to not affect the spins in the next slice in which MR data is to be acquired thereby effectively increasing the TI and increasing SNR and contrast simultaneously. Since the notched saturation pulse saturates all the spins outside of the notched stop-band, the blood in the ventricular chamber is effectively saturated so that the resulting perfusion images have blood pool suppression. Additionally, the use of a 90° presaturation RF pulse provides a high level of immunity to the effects of arrhythmias or other variations in the patient's heart rate. In order to keep the stop-band, or the notch, as wide as possible to overlap the boundaries of each slice location, it is preferable to interleave the acquisition of slice locations.

摘要翻译： 公开了一种使用缺口RF饱和脉冲进行MR灌注采集的方法和装置。 在获取这样的MR数据时，选择要获取MR数据的片段位置量。 每个给定的切片用具有一对通带之间的阻带的缺口RF饱和脉冲来制备。 阻带被设计成不影响将要获取MR数据的下一个切片中的自旋，从而有效地增加TI并同时增加SNR和对比度。 由于缺口饱和脉冲饱和了缺口挡带外的所有旋转，所以心室内的血液被有效地饱和，使得所得到的灌注图像具有血液池抑制。 另外，90°预饱和RF脉冲的使用可以提供高度的抗心律失常作用或其他变化对患者心率的影响。 为了使阻带或陷波尽可能地保持与每个切片位置的边界重叠，优选地切片切片位置的获取。

公开(公告)号：US06377831B1

公开(公告)日：2002-04-23

申请号：US09449432

申请日：1999-11-24

申请人： Viswanathan Seshan ,  J. Andrew Derbyshire ,  Thomas K. F. Foo

发明人： Viswanathan Seshan ,  J. Andrew Derbyshire ,  Thomas K. F. Foo

IPC分类号： A61B505

CPC分类号： G01R33/56308 ,  A61B5/055 ,  G01R33/56

摘要： A system and method for creating MR images using mask data that is copied forward for on-the-fly image subtraction for use within such techniques as MR angiography is disclosed. The invention includes acquiring an MR mask image comprised of a plurality of k-space lines, and then copying the k-space line data of the MR mask image into a number of different memory locations. The number of different memory locations corresponds to a preselected number of MR image acquisitions as set by an MR operator. The invention next includes acquiring the preselected number of MR images, each comprised of k-space line data. As the k-space line data is acquired, it is then immediately accumulated in one of the memory locations having the MR mask image k-space line data. By setting a polarity of the data stored, each acquired k-space line of an acquired MR image is subtracted from a corresponding k-space line of the MR mask image in real time. The image is then reconstructed using the subtracted k-space line data. After each additional MR image acquisition, the data is accumulated with the masked data, which result is used for reconstructing an MR image without the need to transfer the data to another workstation for separate processing or post-processing. In this manner, the acquired data is automatically subtracted on-the-fly, thereby yielding fluoroscopic images, for example, without the prior art penalties of excessive image reconstruction time and image post-processing time.

摘要翻译： 公开了一种用于使用向前复制的掩模数据创建MR图像的系统和方法，用于在例如MR血管造影术的诸如MR血管造影术的技术中使用的即时图像减法。 本发明包括获取由多个k空间线组成的MR掩模图像，然后将MR掩模图像的k空间线数据复制到多个不同的存储器位置。 不同存储器位置的数量对应于由MR操作器设置的预选数量的MR图像采集。 本发明接下来包括获取每个由k空间线数据组成的预选数量的MR图像。 当获取k空间线数据时，它立即被积累在具有MR掩模图像k空间线数据的存储器位置之一中。 通过设置存储的数据的极性，实时地从MR掩模图像的相应的k空间线中减去获取的MR图像的每个获取的k空间线。 然后使用减去的k空间线数据重建图像。 在每次额外的MR图像采集之后，数据用掩蔽的数据累加，这个结果用于重建MR图像，而不需要将数据传送到另一个工作站进行单独的处理或后处理。 以这种方式，所获取的数据被自动减去，从而产生荧光透视图像，例如，没有现有技术对过度图像重建时间和图像后处理时间的惩罚。