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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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2.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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3.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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5.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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6.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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7.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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8.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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9.发明授权Apparatus and methods for magnetic resonance (MR) angiography using hydrogen polarized at low temperatures 失效在低温下使用极化极化的磁共振（MR）血管造影术的装置和方法
公开(公告)号：US5611340A
公开(公告)日：1997-03-18
申请号：US537571
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 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 low-field MR imaging magnet. A catheter is inserted into the patient at or near the root of a vessel tree desired to be imaged. A hydrogen gas is first cooled and condensed into a liquid state, and then passed through the small high-field polarizing magnet where it becomes highly polarized. A contrast fluid is then made by chemically combining the polarized hydrogen with oxygen to obtain highly polarized water. The water is then heated to physiologic temperatures and, if desired, made more physiologically compatible with the addition of substances such as salts. The physiologically conditioned polarized fluid is then 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 the vessel tree being imaged 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低场磁共振（MR）成像磁体，以产生选定血管的MR血管造影。 受试者位于大型低场MR成像磁体中。 在期望成像的血管树的根部处或附近将导管插入患者体内。 首先将氢气冷却并冷凝成液态，然后通过小型高场极化磁铁，在其中高度极化。 然后通过将偏振氢与氧化学组合来获得高极化水来制造造影剂。 然后将水加热至生理温度，并且如果需要，与物质例如盐的添加相比更具生理学相容性。 然后通过导管将生理调节的极化流体引入受试者。 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，所以流体产生比其它组织大得多的MR响应信号，导致血管树以优异的对比度成像。
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公开(公告)号：US5419325A
公开(公告)日：1995-05-30
申请号：US264282
申请日：1994-06-23
IPC分类号： A61B5/055 , G01R33/28 , G01R33/422 , G01R33/561 , G01R33/563 , G06T1/00
CPC分类号： G01R33/285 , G01R33/563 , G01R33/422 , G01R33/5617
摘要： A magnetic resonance (MR) angiography system employs a Faraday catheter for generating MR angiograms of selected blood vessels. A subject is first placed in a polarizing magnetic field. The Faraday catheter is then inserted into a selected blood vessel of the subject at or near the root of a vessel tree desired to be imaged. An MR imaging pulse sequence is then applied to the subject to obtain image information from the region containing the desired vessel tree. Fluid inside the Faraday catheter is shielded from the RF pulses of the MR imaging sequence allowing the fluid to be in a relaxed state, while tissue outside the Faraday catheter is on a steady-state. As the fluid exits the catheter, and before it reaches steady-state, it produces an increased MR response signal causing the desired vessel tree to be imaged.
摘要翻译： 磁共振（MR）血管造影系统采用法拉第导管来产生选定血管的MR血管造影。 首先将被摄体置于极化磁场中。 然后将法拉第导管插入受试者的选定血管中，该血管中希望成像的血管树根部处或附近。 然后将MR成像脉冲序列应用于受试者以从包含所需血管树的区域获得图像信息。 法拉第导管内的流体与MR成像序列的RF脉冲屏蔽，允许流体处于松弛状态，而法拉第导管外的组织处于稳态。 当流体离开导管并且在其达到稳定状态之前，其产生增加的MR响应信号，从而使所需的血管树成像。
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