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公开(公告)号：US06788060B1
公开(公告)日：2004-09-07
申请号：US10250014
申请日：2003-05-28
IPC分类号： G01V300
CPC分类号： G01R33/3875 , G01R33/3873
摘要： An imaging system 10 is provided comprising an imaging magnet 16 having a magnet bore 18. A plurality of passive shims 26 is positioned within the magnet bore 18. A plurality of resistive shims 46 is also positioned within the magnet bore 18. A plurality of thermometers 28 is coupled thermally to a select number of the plurality of passive shims 26 and read a passive shim temperature 36. A controller 32 is in communication with the plurality of thermometers 28 and the plurality of resistive shims 46. The controller 32 includes logic adapted to adjust control currents 40 sent to each of the plurality of resistive shims 46 in response to the resistive shim temperatures 36 received from each of the thermometers 28 such that the strength of the magnetic field and its homogeneity is maintained.
摘要翻译： 提供了一种成像系统10，其包括具有磁体孔18的成像磁体16.多个被动垫片26定位在磁体孔18内。多个电阻垫片46也位于磁体孔18内。多个温度计 28被热耦合到多个被动垫片26的选定数量并读取被动垫片温度36.控制器32与多个温度计28和多个电阻垫片46连通。控制器32包括适于 调节响应于从每个温度计28接收的电阻垫片温度36而发送到多个电阻垫片46中的每一个的控制电流40，使得维持磁场的强度及其均匀性。
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2.发明授权Methods and apparatus for post-exposure determination of ionizing radiation dose 有权电离辐射剂量暴露后测定方法和装置公开(公告)号：US07084628B2
公开(公告)日：2006-08-01
申请号：US10731552
申请日：2003-12-08
IPC分类号： G01V3/00
摘要： The instant invention provides in-vivo methods and apparatus for radiation dosimetry assessment in individuals exposed to potentially harmful radiation, based on measurements in-situ of the teeth. The in vivo dosimetry assessment methods and apparatus utilize electron paramagnetic resonance (EPR) techniques; and employ an apparatus comprising an integrated EPR spectrometer system, an ergonomic magnet and a constructed resonator structure. In various aspects, the dosimetry assessment apparatus is configured to be easily portable and withstand potentially adverse mechanical effects of transportation and deployment in the field. The apparatus also is configured with a power supply that is compatible with both conventional AC line voltages and/or other sources of power suitable for field conditions; and may be easily operated by minimally trained technicians to quickly generate a readout of estimated radiation exposure dose.
摘要翻译： 本发明提供了基于在牙齿原位测量的暴露于潜在有害辐射的个体中的放射剂量测定评估的体内方法和装置。 体内剂量学评估方法和装置利用电子顺磁共振（EPR）技术; 并采用包括集成EPR光谱仪系统，符合人体工程学的磁体和构造的谐振器结构的装置。 在各个方面，剂量测定评估装置被配置为容易携带并且承受在现场的运输和部署的潜在不利的机械效应。 该装置还配置有与常规AC线路电压和/或适用于现场条件的其它电源兼容的电源; 并且可以由训练有素的技术人员容易地操作以快速产生估计的辐射照射剂量的读数。
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公开(公告)号：US08536870B2
公开(公告)日：2013-09-17
申请号：US13066075
申请日：2011-04-06
IPC分类号： G01V3/00
CPC分类号： G01R33/3875
摘要： The present invention is a portable in-bore shim coil insert suitable for correcting high-degree and high-order magnetic field inhomogeneities over a limited examination zone in a magnetic resonance assembly operating above 3 T magnetic field strengths, wherein the magnetic resonance assembly includes at least a MRI magnet having an internal bore of known configuration and volume, at least one set of gradient coils, and an arrangement of radio frequency coils. The in-bore shim coil insert and corresponding method of use is able to produce higher degree and order shimming effects on-demand (i.e., the correction of at least some 3rd to 6th degree field terms or inhomogeneities) and will markedly improve the quality of in-vivo magnetic resonance spectroscopy and/or imaging of any desired anatomic site, i.e., any or all of the various organs, tissues, and systems present in the body of a living subject.
摘要翻译： 本发明是一种便携式内孔衬垫线圈插件，其适用于在高于3T磁场强度的高于3T磁场强度的磁共振组件中的有限检查区域上校正高度和高次磁场不均匀性，其中磁共振组件包括 具有已知构造和体积的内部孔的至少一个MRI磁体，至少一组梯度线圈和射频线圈的布置。 孔内垫片线圈插入物和相应的使用方法能够根据需要产生更高程度和顺序的匀场效果（即，校正至少三到六度场项或不均匀性），并将显着提高质量 体内磁共振光谱学和/或任何所需解剖部位的成像，即存在于活体的身体中的各种器官，组织和系统的任何或全部。
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公开(公告)号：US06294972B1
公开(公告)日：2001-09-25
申请号：US09716779
申请日：2000-11-20
IPC分类号： G01V300
CPC分类号： G01R33/3875 , G01R33/3873
摘要： A local head coil for an MRI system includes a passive shim assembly having ferroshims placed to reduce B0 field inhomogeneities caused by susceptibility effects in the subject being imaged. A prescan is performed with the subject in place to measure B0 field inhomogeneities and the passive shim assembly is tailored to the subject by attaching ferroshim inserts based on these measurements.
摘要翻译： 用于MRI系统的局部头部线圈包括被放置的电子垫片的被动垫片组件，以减少由被成像的被摄体中的易感性影响引起的B0场不均匀性。 执行预扫描以使受试者到位以测量B0场不均匀性，并且基于这些测量，通过附加ferroshim插入物来对受试者定制被动垫片组件。
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公开(公告)号：US4733189A
公开(公告)日：1988-03-22
申请号：US870031
申请日：1986-06-03
IPC分类号： G01R33/3875 , G01R33/421 , G01R33/20
CPC分类号： G01R33/3875 , G01R33/4215
摘要： Novel apparatus and methods for magnetic resonance imaging are disclosed which improve imaging speed and resolution as well as increase efficiency, particularly in superconducting systems. In one aspect of the invention, it has been discovered that the eddy currents and harmonics which normally interfere with MRI operations can be suppressed by the construction of an active shield about the gradient-forming components of the system. The active shield, for example, can be implemented by another set of coils, placed between the gradient coils and the cryostat in a superconducting MRI system to zero particular harmonics and prevent eddy currents in the cryostat shells. By employing a set of active secondary coils the problems associated with eddy currents induced by the gradient producing coils are substantially controlled.
摘要翻译： 公开了用于磁共振成像的新型装置和方法，其提高成像速度和分辨率以及提高效率，特别是在超导系统中。 在本发明的一个方面，已经发现通过围绕系统的梯度形成部件的主动屏蔽的构造可以抑制通常干扰MRI操作的涡流和谐波。 例如，有源屏蔽可以由另一组线圈实现，放置在超导MRI系统中的梯度线圈和低温恒温器之间以消除特定谐波并防止低温恒温器壳中的涡流。 通过采用一组有源次级线圈，基本上控制了由梯度产生线圈引起的与涡流相关的问题。
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