-
1.发明授权Quantitative measurement of blood flow using cylindrically localized Fourier velocity encoding 失效使用圆柱体局部化的速度编码对血液流量的定量测量
公开(公告)号：US5133357A
公开(公告)日：1992-07-28
申请号：US651872
申请日：1991-02-07
CPC分类号： A61B5/7257 , A61B5/0263 , G01R33/563 , A61B5/7285 , G01R33/446
摘要： A method of imaging and quantitatively measuring blood velocity distribution within a selected vessel employs Nuclear Magnetic Resonance cylindrical excitation of the sample to be imaged, followed by Fourier velocity encoding excitation along a second axis for selectively encoding molecules based upon their flow velocities, then sensing the re-radiated signal data acquired in the presence of a readout gradient to provide resolution along the cylindrical axis, and reconstructing a velocity profile. Spatial localization is accomplished with an excitation pulse having a cylindrical rather than slab geometry. This method can be combined with cardiac synchronization to measure flow dynamics or it can be applied without synchronization to measure steady flow. The geometry of the measurement is flexible in that the directions of flow sensitivity and geometric resolution are independent.
-
2.发明授权
公开(公告)号：US5578924A
公开(公告)日：1996-11-26
申请号：US558296
申请日：1995-11-15
CPC分类号： G01R33/4835 , G01R33/4833
摘要： A multi-planar imaging method employs magnetic resonance to detect image data from multiple planes within a subject. Data from each plane are detected in response to the same readout gradient and are simultaneously detected. The image planes can be arbitrarily oriented with respect to each other and with respect to the readout and phase-encoding image formation magnetic field gradient pulses if desired. Overlap of image data from each of the excited image planes in the acquired image is prevented by employing a thick refocusing slab oriented orthogonal to the readout and phase-encoding directions, or by choosing planes which intersect outside the subject's anatomy.
摘要翻译： 多平面成像方法采用磁共振来检测受试者内的多个平面的图像数据。 根据相同的读出梯度检测来自每个平面的数据，并同时检测。 如果需要，图像平面可以相对于彼此和相对于读出和相位编码图像形成磁场梯度脉冲任意取向。 通过采用与读出和相位编码方向正交取向的厚度重聚焦板，或通过选择与被摄体的解剖结构外部相交的平面来防止获取的图像中的每个激发的图像平面上的图像数据的重叠。
-
3.发明授权
公开(公告)号：US5548216A
公开(公告)日：1996-08-20
申请号：US558298
申请日：1995-11-15
CPC分类号： G01R33/4835
摘要： A multi-planar imaging method employs magnetic resonance to detect image data from multiple planes within a subject. Data from each plane are detected in response to the same readout gradient and are simultaneously detected. The image planes can be arbitrarily oriented with respect to each other and with respect to the readout and phase-encoding image formation magnetic field gradient pulses if desired. Overlap of image data from each of the excited image planes in the acquired image is prevented by modulating the phase of each RF excitation pulse in concert with the amplitude of the phase-encoding gradient pulse to cause the image data from each excitation plane to be displaced by a unique amount in the phase-encoding direction.
摘要翻译： 多平面成像方法采用磁共振来检测受试者内的多个平面的图像数据。 根据相同的读出梯度检测来自每个平面的数据，并同时检测。 如果需要，图像平面可以相对于彼此和相对于读出和相位编码图像形成磁场梯度脉冲任意取向。 通过与相位编码梯度脉冲的振幅一致地调制每个RF激励脉冲的相位来防止来自获取的图像中的每个激发的图像平面的图像数据的重叠，从而使来自每个激励平面的图像数据移位 通过相位编码方向的独特量。
-
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。
-
5.发明授权Polarization transfer by selective homonuclear technique for suppression of uncoupled spins in NMR spectroscopy 失效通过选择性同核技术在NMR光谱学中抑制非偶联自旋的极化转移
公开(公告)号：US4701708A
公开(公告)日：1987-10-20
申请号：US891823
申请日：1986-08-01
CPC分类号： G01R33/4608
摘要： A method of suppressing at least one undesired resonance response signal while facilitating reception of at least one other desired NMR response signal from a coupled spin resonance in NMR spectroscopy, utilizes a pair of alternating sequences of RF signal pulses, with each sequence having an initial .pi./2 RF pulse, followed by a .pi. RF signal pulse having a temporal midpoint at a time interval T after the temporal midpoint of the initial pulse (where T=n/4J, with n being an odd integer and J being the spin coupling constant of the hydrogen nuclei) and a final .pi. RF signal pulse with a temporal midpoint at twice the time interval T after the temporal midpoint of the first .pi. RF signal pulse in that sequence. Only one of the pair of sequences is provided with a polarization transfer narrowband .pi. RF signal pulse symmetrically disposed about a temporal midpoint located at substantially a time interval T after the first .pi. RF signal pulse of that sequence and substantially at a frequency removed from the resonance frequency of at least one undesired uncoupled spin resonance. Response signals are acquired within a gating period including a temporal point thereof occurring at a time interval T after the temporal midpoint of the final .pi. RF signal pulse. The pair of recovered sets of data are substracted from one another to obtain a final data set in which noncoupled spin resonance data is substantially cancelled but desired coupled spin resonance data is preserved.
摘要翻译： 抑制至少一种不期望的共振响应信号的方法同时有利于从NMR光谱中从耦合的自旋共振接收至少一种其它期望的NMR响应信号，利用一对RF信号脉冲的交替序列，其中每个序列具有初始pI / 2 RF脉冲，其后是在初始脉冲的时间中点（其中T = n / 4J，其中n为奇整数，J为自旋耦合常数）的时间间隔T之后具有时间中点的pi RF信号脉冲 的氢核）和最终的pi RF信号脉冲，其具有在该序列中的第一pi RF信号脉冲的时间中点之后的时间间隔T的两倍的时间中点。 该对序列中只有一个被提供有偏振转移窄带pi RF信号脉冲，该偏振转移窄带pi RF信号脉冲对称地设置在该序列的第一pi RF信号脉冲之后的基本上位于时间间隔T的时间中点处，并且基本上以从谐振 至少一个不期望的非偶联自旋共振的频率。 响应信号在门控周期内获取，包括在最终的pi RF信号脉冲的时间中点之后的时间间隔T出现的时间点。 一对恢复的数据集彼此相减，以获得最终数据集，其中非耦合自旋共振数据被基本上取消，但保留了所需的耦合自旋谐振数据。
-
公开(公告)号：US20120253176A1
公开(公告)日：2012-10-04
申请号：US13509324
申请日：2010-11-04
申请人： Charles L. Dumoulin
发明人： Charles L. Dumoulin
CPC分类号： A61N7/02 , A61B8/565 , A61B2017/00084 , A61B2090/374 , A61N2007/0008 , A61N2007/0065 , A61N2007/0082
摘要： Systems and methods for debulking visceral fat within a subject, include: providing a focused ultrasound transducer configured to focus ultrasonic power at a focal spot; positioning the focused ultrasound transducer with respect to the subject so that the focused ultrasound transducer is enabled to transfer ultrasonic power into the subject; locating the focal spot of the focused ultrasound transducer with respect to at least one target region containing visceral fat within the subject; and debulking visceral fat within the target region by applying ultrasonic energy from the focused ultrasound transducer with sufficient power to cause the death of visceral fat tissue within the target region.
摘要翻译： 用于在受试者内减毒内脏脂肪的系统和方法包括：提供配置成在焦斑处聚焦超声波功率的聚焦超声波换能器; 将聚焦的超声换能器相对于对象定位，使得聚焦的超声换能器能够将超声功率传送到被摄体中; 相对于在受试者内含有内脏脂肪的至少一个目标区域定位聚焦超声换能器的焦点; 并通过从聚焦的超声换能器中施加超声波能量以足够的力量引起目标区域内脏脂肪组织的死亡，从而在目标区域内减压内脏脂肪。
-
7.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。
-
8.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。
-
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。
-
10.发明授权
公开(公告)号：US5285260A
公开(公告)日：1994-02-08
申请号：US909275
申请日：1992-07-06
申请人： Charles L. Dumoulin
发明人： Charles L. Dumoulin
CPC分类号： G01N21/1702 , G01B17/04 , G01N21/171 , A61B5/0066
摘要： An optical interferometer and an ultrasonic distance measuring subsystem are used to obtain spectra from the surface of a sample. The interferometer uses a broadband electromagnetic radiation source and modulates the radiation at a frequency which is inversely proportional to wavelength. The modulated radiation impinges on the surface of interest where it is absorbed. The absorption of radiation causes the surface of the sample to expand. This change in dimension is then detected by the ultrasonic distance measuring subsystem which employs a single frequency acoustic radiation source to measure the instantaneous distance between the sample surface and the ultrasonic distance measurement subsystem. The detected changes in distance relate to amplitude of absorption at a given wavelength, thereby allowing absorption spectra for surface point to be generated indicating the chemical composition of each point of the surface.
摘要翻译： 使用光学干涉仪和超声波距离测量子系统从样品的表面获得光谱。 干涉仪使用宽带电磁辐射源，并以与波长成反比的频率调制辐射。 调制的辐射照射在感兴趣的表面上，在其被吸收的地方。 辐射的吸收导致样品的表面膨胀。 然后，超声波距离测量子系统检测尺寸变化，该子系统采用单声频辐射源来测量样品表面和超声波距离测量子系统之间的瞬时距离。 检测到的距离变化与给定波长处的吸收幅度有关，从而允许产生指示表面各点的化学成分的表面点的吸收光谱。
-
-
-
-
-
-
-
-
-
搜索结果
69 条记录 (耗时 0.032 秒)
