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公开(公告)号：EP1658510A1
公开(公告)日：2006-05-24
申请号：EP04744595.2
申请日：2004-07-16
IPC分类号： G01R33/28 , G01R33/341 , G01R33/3415
CPC分类号： G01R33/28 , G01R33/341 , G01R33/3415
摘要： A novel magnetic resonance imaging method is described, which is provided for planning a small Field-of-View for a surface coil (3, 5) at the region of interest of a patient lying on a support movable through the bore of a main magnet. A magnetic resonance signal is generated in an examination zone by means of an RF pulse (7). This magnetic resonance signal is subsequently detected by means of the surface coil and under the influence of magnetic field gradients. A non-selective RF-pulse (7) and a first gradient pulse (8) having a linearly independent spatial direction are generated in temporal succession, so that the position of the surface coil (3, 5) in said spatial direction with respect to the isocenter of the main magnet can be determined by the center of gravity of the Fourier transformed response signals detected by the surface coil.
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公开(公告)号：EP1642151A1
公开(公告)日：2006-04-05
申请号：EP04743843.7
申请日：2004-06-30
IPC分类号： G01R33/58
CPC分类号： G01R33/28 , A61B5/055 , G01R33/288 , G01R33/583
摘要： An MRI apparatus is provided. The apparatus includes a main magnet for generating a main magnetic field in an examination region, a plurality of gradient coils for generating gradient fields within the main field, an RF transmit coil for transmitting RF signals into the examination region and exciting magnetic resonance in a subject disposed therein in accordance with a plurality of imaging parameters, the transmitted RF signals having a SAR associated therewith, and a SAR processor for maintaining the transmitted RF signals below a prescribed SAR level.
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公开(公告)号：EP1642149A1
公开(公告)日：2006-04-05
申请号：EP04731084.2
申请日：2004-05-04
发明人： FUDERER, Miha
IPC分类号： G01R33/561
CPC分类号： G01R33/5611 , G01R33/56308
摘要： A novel magnetic resonance imaging method is described for forming a sequence of images from a plurality of signals acquired by at least one receiver antenna. Each receiver antenna has a spatial sensitivity profile. An activity map is calculated as a standard deviation over a series of images acquired by a reference scan. Thereupon, the object is sampled in an actual scan in an interleaved manner in k-space with a reduction factor. The resulting data is Fourier transformed to the spatial domain to form a sequence of folded preliminary images, and the fold-over artefacts or the ambiguity in the preliminary images resulting from the undersampled data in k-space is resolved in forming the actual images on the basis of the activity map.
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104.发明公开
公开(公告)号：EP1639384A1
公开(公告)日：2006-03-29
申请号：EP04735630.8
申请日：2004-06-01
IPC分类号： G01R33/561
CPC分类号： G01R33/5611
摘要： A magnetic resonance imaging system acquires a final image of a selected field of view with a selected spatial resolution. A magnetic resonance imaging scanner (10) encodes and receives magnetic resonance samples in phase encode and readout directions using a plurality of receive coils (14). The encoding and receiving undersamples in the readout direction. A reconstruction processor (30) reconstructs magnetic resonance samples acquired by each of the plurality of receive coils (14) into a corresponding plurality of intermediate reconstructed images. Each intermediate reconstructed image has aliasing and in some aspects degraded high spatial frequency characteristics due to the reduced sampling in the readout direction. A combining processor (40) combines the plurality of intermediate reconstructed images based on coil sensitivity factors (42) to produce the final reconstructed image with the selected field of view and the selected spatial resolution in the readout direction.
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105.发明公开
公开(公告)号：EP1639381A2
公开(公告)日：2006-03-29
申请号：EP04737090.3
申请日：2004-06-21
IPC分类号： G01R33/341
CPC分类号： G01R33/3642 , G01R33/341
摘要： The invention relates to a radio-frequent (RF) coil system (17, 17’) for use in a magnetic resonance imaging (MRI) system. The RF coil system comprises at least one main coil (35) for transmitting an RF magnetic field (B1) into and/or receiving an RF magnetic field (B1’) from an examination volume (3) of the MRI system. The main coil has a main coil axis (37), which is or is to be oriented parallel to a main magnetic field (B0) in the examination volume, and at least one electrical conductor (39, 41) which extends mainly parallel to the main coil axis. According to the invention, the RF coil system comprises at least two electrical auxiliary coils (51, 53, 55, 57) which are assigned to said conductor of the main coil. The auxiliary coils are arranged on opposite sides of said conductor of the main coil. Each auxiliary coil has a coil axis (59, 61, 63, 65) which extends substantially parallel to the main coil axis at a distance from the conductor of the main coil to which the respective auxiliary coil is assigned, said distance being small relative to a main dimension (L) of the main coil. The auxiliary coils constitute passive electrical coils in which electrical currents are generated under the influence of an RF magnetic field (B11, B11’) present at the location of the auxiliary coils. The RF magnetic field (B12, B34) generated by the auxiliary coils as a result of said currents in the auxiliary coils suppresses said RF magnetic field present at the location of the auxiliary coils. Thus, the auxiliary coils provide a sensitivity reducing effect of the RF coil system in local regions (47, 49) which are at relatively small distances from the conductor of the main coil. For regions at a distance from the conductor of the main coil comparable to the main dimension of the main coil, said sensitivity reducing effect is negligible.
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公开(公告)号：EP1639344A1
公开(公告)日：2006-03-29
申请号：EP04744392.4
申请日：2004-06-23
发明人： MAZNEV, Alexei
CPC分类号： G01N29/4427 , G01N21/636 , G01N29/07 , G01N29/2418 , G01N29/30 , G01N2291/0237 , G01N2291/0423
摘要： The present invention uses ISTS to measure trenches with near- or sub-micron width. The trenches can be etched in a thin film on in a silicon substrate. One step of the method is exciting the structure by irradiating it with a spatially periodic laser intensity pattern in order to generate surface acoustic waves. Other steps are diffracting a probe laser beam off the thermal grating to form a signal beam; detecting the signal beam as a function of time to generate a signal waveform; determining surface acoustic wave phase velocity from the waveform; and determining at least one property of the trench structures based on the dependence of surface acoustic wave phase velocity on the parameters of the structure.
摘要翻译： 本发明使用ISTS来测量具有接近或亚微米宽度的沟槽。 沟槽可以蚀刻在硅衬底上的薄膜上。 该方法的一个步骤是通过用空间周期性激光强度图案照射该结构来激发该结构以便产生表面声波。 其他步骤是将探测激光束衍射离开热光栅以形成信号光束; 检测作为时间函数的信号光束以产生信号波形; 从波形中确定表面声波相位速度; 以及基于表面声波相速度对结构参数的依赖性来确定沟槽结构的至少一个性质。
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公开(公告)号：EP1633245A1
公开(公告)日：2006-03-15
申请号：EP04733885.0
申请日：2004-05-19
发明人： VAN ES, Arthur, R.
CPC分类号： A61B6/04 , A61B5/0555 , Y10S5/943
摘要： The invention relates to a device for the examination of persons, said device comprising a medical examination device (11) having an examination volume (12), a support (1) for a person to be examined, and displacing means (3) for displacing the support in a displacement direction in such a manner, that a person to be examined present on the support is displaced into and out of the examination volume. Said displacing means comprise a gearwheel (7), which is driven by driving means (5, 8) and is co-operating with a toothed rack (4) mounted to the support for displacing the toothed rack relative to the gear-wheel in the driven state of the gear-wheel. The displacing means comprise sub-displacing means (6, 9) for displacing the gear-wheel in its driven state in the displacement direction with a speed which is lower than the speed of support.
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公开(公告)号：EP1629293A1
公开(公告)日：2006-03-01
申请号：EP04733413.1
申请日：2004-05-17
IPC分类号： G01R33/385
CPC分类号： G01R33/3854
摘要： The invention provides a magnetic resonance imaging (MRI) device (21), comprising a diagnostic space (25), a main magnetic system (22) for generating a main magnetic field in said diagnostic space, a gradient magnetic coil system (23) comprising a gradient coil for generating at least one gradient of the main magnetic field, and noise reducing means (29, 32) for reducing noise that is generated as a result of vibrations of the gradient coil. The noise reducing means comprise a sound-absorbing panel (29) disposed between the gradient coil and the diagnostic space. The sound-absorbing panel (29) comprises channels having an open end and a closed end.
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公开(公告)号：EP1620747A1
公开(公告)日：2006-02-01
申请号：EP04728879.0
申请日：2004-04-22
发明人： HOOGENRAAD, Frank, G., C. , VAN MUISWINKEL, Arianne, M., C. , HOLTHUIZEN, Ronaldus, F., J. , VAN DEN BRINK, Johan, S.
IPC分类号： G01R33/563
CPC分类号： G01R33/56341 , G01R33/4806
摘要： A method of deriving a directional structure from an object dataset is proposed. The object dataset assigns local directions to positions in a multidimensional geometrical space. For example the local directions concern local flow directions in a diffusion tensor magnetic resonance image at least one `region of interest' is selected on the basis of spatial functional information, such as an fMRI image, time correlation of an fMRI image series with a functional paradigm or an anatomical image. These `region of interest' are employed to initialize a fibre tracking to derive the directional structure that represents the nervous fibre system.
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公开(公告)号：EP1616199A1
公开(公告)日：2006-01-18
申请号：EP04725778.7
申请日：2004-04-05
IPC分类号： G01R33/563
CPC分类号： G01R33/56341 , G01R33/5608
摘要： The invention relates to a system for displaying fibre tracts of a human or animal, comprising memory means holding diffusion images of a region of interest of said human or animal, processing means connected to the memory means for deriving fibre tract data from the diffusion images, and display means for displaying the fibre tracts derived by the processing means wherein the processing means include a discriminator to select the fibre tract data to be displayed on the display means.
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