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1.发明授权Apparatus and methods for magnetic resonance (MR) imaging of cavities using fluids polarized at low temperatures 失效使用在低温下极化的流体对空腔进行磁共振（MR）成像的装置和方法
公开(公告)号：US5617859A
公开(公告)日：1997-04-08
申请号：US537574
申请日：1995-10-02
IPC分类号： A61B5/055
CPC分类号： A61B5/055
摘要： A magnetic resonance (MR) active invasive device system employs a small, high-field polarizing magnet, and a large magnetic resonance (MR) imaging magnet for the purpose of generating MR images of selected body cavities. A subject is positioned in a large low-field MR imaging magnet. A substance, intended to be used as a contrast agent is first cooled, and then passed through the small high-field polarizing magnet where it becomes highly polarized. The substance is then heated to physiologic temperatures, vaporized, and introduced into the subject through a transfer conduit as a vapor. Radiofrequency (RF) pulses and magnetic field gradients are then applied to the patient as in conventional MR imaging. Since the vapor is highly polarized, it can be imaged even though it has a much lower density than the surrounding tissue.
摘要翻译： 磁共振（MR）有源侵入性装置系统采用小型高场极化磁体和大型磁共振（MR）成像磁体，用于产生选定体腔的MR图像。 受试者位于大型低场MR成像磁体中。 首先将要用作造影剂的物质冷却，然后通过小型高场极化磁体，在其中高度极化。 然后将物质加热至生理温度，蒸发，并通过作为蒸气的转移导管引入受试者。 然后将射频（RF）脉冲和磁场梯度应用于患者，如在常规MR成像中。 由于蒸气是高度极化的，所以即使其具有比周围组织低得多的密度，也可以成像。
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公开(公告)号：US5365927A
公开(公告)日：1994-11-22
申请号：US146345
申请日：1993-11-02
申请人： Peter B. Roemer , Samuel M. Blumenfeld , Kirby G. Vosburgh , Harvey E. Cline , William D. Barber , William E. Lorensen , Richard L. St. Peters , John F. Schenck , Charles L. Dumoulin , Robert D. Darrow , Christopher J. Hardy
发明人： Peter B. Roemer , Samuel M. Blumenfeld , Kirby G. Vosburgh , Harvey E. Cline , William D. Barber , William E. Lorensen , Richard L. St. Peters , John F. Schenck , Charles L. Dumoulin , Robert D. Darrow , Christopher J. Hardy
IPC分类号： G01R33/48 , A61B5/055 , G01R33/28 , G01R33/38 , G01R33/385 , G01R33/54 , G01R33/563
CPC分类号： G01R33/385 , G01R33/3806 , G01R33/285 , G01R33/4804 , G01R33/543 , G01R33/563
摘要： A magnetic resonance (MR) imaging system for use in a medical procedure employs an open main magnet allowing access to a portion of a patient within an imaging volume, for producing a main magnetic field over the imaging volume; a set of open gradient coils which provide magnetic fields gradients over the imaging volume without restricting access to the imaging volume; a radiofrequency coil set for transmitting RF energy into the imaging volume to nutate nuclear spins within the imaging volume and receive an MR response signal from the nuclear spins; and a pointing device for indicating the position and orientation of a plane in which an image is to be acquired; an image control means for operating power supplies for the gradient coils and the RF coils to acquire an MR signal from the desired imaging plane; and a computation unit for constructing an image of the desired imaging plane. The MR imaging system is intended to operate to provide images to a physician during medical procedures to guide the physician in his procedures.
摘要翻译： 用于医疗过程的磁共振（MR）成像系统采用打开的主磁体，其允许进入成像体积内的患者的一部分，用于在成像体积上产生主磁场; 一组开放的梯度线圈，其在成像体积上提供磁场梯度，而不限制对成像体积的访问; 射频线圈组，用于将RF能量传输到成像体积中，以在成像体积内盘旋核自旋，并从核自旋接收MR响应信号; 以及指示装置，用于指示要获取图像的平面的位置和方位; 图像控制装置，用于操作梯度线圈和RF线圈的电源，以从期望的成像平面获取MR信号; 以及用于构造所需成像平面的图像的计算单元。 MR成像系统旨在在医疗程序期间向医生提供图像以在他的程序中指导医师。
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3.发明授权
公开(公告)号：US5318025A
公开(公告)日：1994-06-07
申请号：US861690
申请日：1992-04-01
IPC分类号： A61B5/055 , A61B5/06 , A61B19/00 , G01R33/28 , G01R33/32 , G01R33/561 , G01R33/563
CPC分类号： A61B5/06 , A61B5/055 , G01R33/285 , G01R33/563 , A61B2090/3958 , G01R33/5617
摘要： A tracking system employs magnetic resonance signals to monitor the position and orientation of at least one device such as a catheter within a subject. The device has a plurality of receiver coils which are sensitive to magnetic resonance signals generated in the subject. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to sequentially applied mutually orthogonal magnetic gradients to determine the device's position and orientation in several dimensions. The position and orientation of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images. One or more devices can be simultaneously tracked.
摘要翻译： 跟踪系统采用磁共振信号来监测至少一个装置（例如对象内的导管）的位置和取向。 该装置具有对受试者中产生的磁共振信号敏感的多个接收线圈。 在存在磁场梯度的情况下检测这些信号，因此具有与沿施加的梯度方向的线圈位置基本成比例的频率。 响应于顺序施加的相互正交的磁梯度来检测信号，以在几个维度中确定装置的位置和取向。 由跟踪系统确定的设备的位置和方向被叠加在独立获取的医学诊断图像上。 可以同时跟踪一个或多个设备。
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4.发明授权Apparatus and methods for magnetic resonance (MR) angiography using fluids polarized at low temperatures 失效使用在低温下极化的流体进行磁共振（MR）血管造影术的装置和方法
公开(公告)号：US5626137A
公开(公告)日：1997-05-06
申请号：US537572
申请日：1995-10-02
IPC分类号： A61B5/055
CPC分类号： A61B5/055
摘要： A magnetic resonance (MR) active invasive device system employs a small, high-field polarizing magnet, and a large, possibly low-field magnetic resonance (MR) imaging magnet for the purpose of generating MR angiograms of selected blood vessels. A subject is positioned in a large MR imaging magnet. A catheter is inserted into the patient at or near the root of a vessel tree to be imaged. A fluid, intended to be used as a contrast agent is first cooled and frozen, and then passed through the small high-field polarizing magnet where it becomes highly polarized. The frozen fluid is then heated and melted to physiologic temperatures and introduced into the subject through the catheter. Radiofrequency (RF) pulses and magnetic field gradients are then applied to the patient as in conventional MR imaging. Since the fluid has a larger longitudinal magnetization than tissue which has not passed through the polarizing magnet, the fluid produces a much larger MR response signal than other tissue, resulting in vessel tree images with excellent contrast.
摘要翻译： 磁共振（MR）主动侵入性装置系统采用小型，高场极化磁体和大型可能的低场磁共振（MR）成像磁体，用于产生选定血管的MR血管造影。 受试者位于大型MR成像磁体中。 在要成像的血管树的根部处或附近将导管插入患者体内。 首先将要用作造影剂的流体冷却并冷冻，然后通过小型高场极化磁体，在其中高度极化。 然后将冷冻的流体加热并熔化成生理温度并通过导管引入受试者。 然后将射频（RF）脉冲和磁场梯度应用于患者，如在常规MR成像中。 由于流体具有比没有通过偏振磁体的组织更大的纵向磁化强度，所以流体产生比其他组织大得多的MR响应信号，导致具有优异对比度的容器树图像。
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公开(公告)号：US5577502A
公开(公告)日：1996-11-26
申请号：US415409
申请日：1995-04-03
CPC分类号： A61B5/721 , A61B34/20 , A61B5/06 , A61B5/1135 , A61B8/0833 , A61B8/5276 , A61B2017/00694 , A61B5/7289
摘要： A tracking system monitors the position of a device within a subject and superimposes a graphic symbol on a diagnostic image of the subject. Registration of the tracked location with the diagnostic image is maintained in the presence of subject motion by monitoring subject motion and adjusting the display to compensate for subject motion. Motion monitoring can be performed with ultrasonic, optical or mechanical methods. The display can be adjusted by modifying the displayed location of the device or it can be adjusted by translating, rotating or distorting the diagnostic image.
摘要翻译： 跟踪系统监视对象内的设备的位置并将图形符号叠加在被摄体的诊断图像上。 通过监视对象运动并调整显示以补偿被摄体运动，通过诊断图像对被跟踪位置的注册保持在受试者运动的存在下。 运动监测可以用超声波，光学或机械方法进行。 可以通过修改显示的设备位置来调整显示，也可以通过翻译，旋转或扭曲诊断图像进行调整。
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6.发明授权Tracking system to monitor the position and orientation of a device using magnetic resonance detection of a sample contained within the device 失效跟踪系统用于使用包含在该装置内的样本的磁共振检测来监测装置的位置和方位
公开(公告)号：US5271400A
公开(公告)日：1993-12-21
申请号：US861662
申请日：1992-04-01
IPC分类号： A61B5/055 , A61B5/06 , A61B5/07 , G01R33/28 , G01R33/561 , G01R33/563
CPC分类号： G01R33/563 , A61B5/055 , A61B5/06 , G01R33/285 , G01R33/5617
摘要： A tracking system employs magnetic resonance signals to monitor the position and orientation of a device, such as a catheter, within a subject. The device has an MR active sample and a receiver coil which is sensitive to magnetic resonance signals generated by the MR active sample. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to sequentially applied mutually orthogonal magnetic gradients to determine the device's position in several dimensions. The position of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images. One or more devices can be simultaneously tracked.
摘要翻译： 跟踪系统采用磁共振信号来监测被检体内的装置（例如导管）的位置和方位。 该器件具有对MR活性样品产生的磁共振信号敏感的MR活性样品和接收器线圈。 在存在磁场梯度的情况下检测这些信号，因此具有与沿施加的梯度方向的线圈位置基本成比例的频率。 响应于顺序施加的相互正交的磁梯度来检测信号以确定器件在几个维度中的位置。 由跟踪系统确定的设备的位置叠加在独立获取的医学诊断图像上。 可以同时跟踪一个或多个设备。
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7.发明授权Tracking system to monitor the position of a device using multiplexed magnetic resonance detection 失效跟踪系统监视使用复用磁共振检测的设备的位置
公开(公告)号：US5353795A
公开(公告)日：1994-10-11
申请号：US989283
申请日：1992-12-10
IPC分类号： A61B5/06 , G01R33/28 , G01R33/561 , G01R33/563 , A61B5/055
CPC分类号： G01R33/285 , A61B5/06 , G01R33/563 , G01R33/5617
摘要： A tracking system employs magnetic resonance signals to monitor the position of a device such as a catheter within a subject. The device has a receiver coil which is sensitive to magnetic resonance signals generated in the subject. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to applied magnetic gradients to determine the position of the device in several dimensions. Sensitivity of the measured position to resonance offset conditions such as transmitter frequency misadjustment, chemical shift and the like is minimized by repeating the process a plurality of times with selected amplitudes and polarities for the applied magnetic field gradient. Linear combinations of the data acquired responsive to the different applied magnetic field gradients are computed to determine the position of the device in three orthogonal dimensions. The position of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images.
摘要翻译： 跟踪系统采用磁共振信号来监测被检体内诸如导管之类的装置的位置。 该装置具有对受试者中产生的磁共振信号敏感的接收器线圈。 在存在磁场梯度的情况下检测这些信号，因此具有与沿施加的梯度方向的线圈位置基本成比例的频率。 响应于所施加的磁梯度检测信号以确定装置在几个维度中的位置。 通过用所施加的磁场梯度的选定幅度和极性重复该过程多次来最小化测量位置对谐振偏移条件（例如发射机频率误调整，化学位移等）的灵敏度。 计算响应于不同施加的磁场梯度采集的数据的线性组合，以确定装置在三个正交尺寸中的位置。 由跟踪系统确定的设备的位置叠加在独立获取的医学诊断图像上。
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8.发明授权Tracking system and pulse sequences to monitor the position of a device using magnetic resonance 失效跟踪系统和脉冲序列来监控使用磁共振的设备的位置
公开(公告)号：US5307808A
公开(公告)日：1994-05-03
申请号：US861718
申请日：1992-04-01
IPC分类号： A61B5/055 , A61B5/06 , G01R33/28 , G01R33/32 , G01R33/561 , G01R33/563
CPC分类号： G01R33/285 , G01R33/563 , G01R33/5617
摘要： A tracking system employs magnetic resonance signals to monitor the position of a device such as a catheter within a subject. The device has a receiver coil which is sensitive to magnetic resonance signals generated in the subject. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to sequentially applied mutually orthogonal magnetic gradients to determine the position of the device in several dimensions. The position of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images.
摘要翻译： 跟踪系统采用磁共振信号来监测被检体内诸如导管之类的装置的位置。 该装置具有对受试者中产生的磁共振信号敏感的接收器线圈。 在存在磁场梯度的情况下检测这些信号，因此具有与沿施加的梯度方向的线圈位置基本成比例的频率。 响应于顺序施加的相互正交的磁梯度来检测信号，以确定器件在几个维度中的位置。 由跟踪系统确定的设备的位置叠加在独立获取的医学诊断图像上。
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9.发明授权Tracking system to follow the position and orientation of a device with radiofrequency field gradients 失效跟踪系统遵循具有射频场梯度的设备的位置和方向
公开(公告)号：US5211165A
公开(公告)日：1993-05-18
申请号：US753565
申请日：1991-09-03
CPC分类号： A61B5/06 , A61B6/12 , G01V3/104 , A61B2034/2051
摘要： A tracking system in which radiofrequency signals emitted by an invasive device such as a catheter are detected and used to measure the position and orientation of the invasive device within a subject. Detection of the radiofrequency signals is accomplished with coils having sensitivity profiles which vary approximately linearly with position. The invasive device has a transmit coil attached near its end and is driven by a low power RF source to produce a dipole electromagnetic field that can be detected by an array of receive coils distributed around a region of interest of the subject. The position and orientation of the device as determined by the tracking system are superimposed upon independently acquired Medical Diagnostic images, thereby minimizing the diagnostic exposure times. One or more invasive devices can be simultaneously tracked.
摘要翻译： 检测由诸如导管的侵入性装置发射的射频信号并用于测量受试者内的侵入性装置的位置和取向的跟踪系统。 射频信号的检测是用具有随位置近似线性变化的灵敏度分布的线圈来实现的。 侵入性装置具有靠近其端部附接的发射线圈，并且由低功率RF源驱动以产生可以通过分布在受试者的感兴趣区域周围的接收线圈阵列来检测的偶极电磁场。 由跟踪系统确定的设备的位置和方向叠加在独立获取的医学诊断图像上，从而最小化诊断曝光时间。 可以同时跟踪一个或多个入侵设备。
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10.发明授权Method for blood flow acceleration and velocity measurement using MR catheters 失效使用MR导管进行血流加速和速度测量的方法
公开(公告)号：US5445151A
公开(公告)日：1995-08-29
申请号：US264281
申请日：1994-06-23
CPC分类号： A61B5/0263 , G01F1/716 , G01P5/18 , G01R33/285 , G01R33/34084 , G01R33/56308
摘要： A method of magnetic resonance (MR) fluid flow measurement within a subject employs an invasive device with an RF transmit/receive coil and an RF transmit coil spaced a known distance apart. The subject is positioned in a static magnetic field. The invasive device is positioned in a vessel of a subject in which fluid flow is desired to be determined. A regular pattern of RF transmission pulses are radiated through the RF transmit/receive coil causing it to cause a steady-state MR response signal. Intermittently a second RF signal is transmitted from the RF coil positioned upstream which causes a change in the steady-state MR response signal sensed by the downstream transmit/receive coil. This is detected a short delay time later at the RF receive coil. The time delay and the distance between the RF coils leads directly to a fluid velocity. By exchanging the position of the RF transmit and transmit/receive coils, retrograde velocity may be measured. In another embodiment, more RF coils are employed. The changed MR response signal may be sensed at a number of locations at different times, leading to a measured change in velocity, or acceleration of the fluid.
摘要翻译： 在受试者内的磁共振（MR）流体流量测量的方法使用具有RF发射/接收线圈和间隔已知距离的RF发射线圈的侵入性装置。 被摄体位于静态磁场中。 将侵入性装置定位在需要确定流体流动的受试者的血管中。 通过RF发射/接收线圈辐射RF传输脉冲的规则图案，使其产生稳态MR响应信号。 间歇地从位于上游的RF线圈发送第二RF信号，引起下游发射/接收线圈感测到的稳态MR响应信号的变化。 在RF接收线圈之后检测到短时间延迟时间。 时间延迟和RF线圈之间的距离直接导致流体速度。 通过交换RF发射和发射/接收线圈的位置，可以测量逆行速度。 在另一个实施例中，采用更多的RF线圈。 可以在不同时间的多个位置处感测改变的MR响应信号，导致测量的流体变化或流体的加速度。
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