摘要:
A dispenser (132), a magnetic resonance imaging system (100), and a method for using hyperpolarized contrast agent (304) during a magnetic resonance imaging examination. The dispenser comprises an attachment component (136) for a face piece (138). The face piece is adapted for receiving the surface of a subject (114) such that when the subject inhales hyperpolarized contrast agent enters the respiratory system of the subject. The dispenser further comprises a reservoir (300) adapted for receiving the hyperpolarized contrast agent. The dispenser further comprises a gas flow (406) tube connected to the attachment component and a vaporizer (406, 408, 412, 510, 602, 606) for vaporizing the hyperpolarized contrast agent in the gas flow tube into a hyperpolarized vapor. The dispenser further comprises a controller (402) for controlling when the vaporizer vaporizes the hyperpolarized contrast agent.
摘要:
The invention relates to a dynamic nuclear polarization apparatus (116) for continuous provision of hyperpolarized samples (114) comprising dynamically nuclear polarized nuclear spins, the apparatus (116) comprising a polarization region (106) for polarization of said nuclear spins resulting in said hyperpolarized samples, wherein the apparatus (116) further comprises: a cryostat (102) for cooling the samples (114) in the polarization region (106), a magnet (100) for providing a magnetic field to the cooled samples in the polarization region (106), a radiation source (112) for concurrently to the magnetic field provision providing a nuclear polarizing radiation to the polarization region (106) for receiving the hyperpolarized samples, a sample transport system (104) for continuously receiving unpolarized samples (114), transporting the unpolarized samples to the polarization region (106) for nuclear spin polarization and providing the resulting hyperpolarized samples (114).
摘要:
A magnet system, in particular for a magnetic resonance examination system, comprises a superconductive main magnet having a near group of coil windings and a remote group of coil windings. A gradient coil system forms a source of power dissipation into at least part of the coil windings. The near group of coil windings and the remote group of coil windings are near and remote from the source of power dissipation, respectively A cooling system has a high-temperature cooling station and a low-temperature cooling station. The high-temperature cooling station cools mainly the near group of coil windings. The low temperature cooling station cools mainly the remote group of coil windings. The near and remote group optionally are made of different superconductive materials. Thus, additional degrees of freedom are achieved which allow less expensive magnet design.
摘要:
An electromagnet comprises: a ferromagnetic core (50, 72); electrically conductive windings (34, 76) disposed around the ferromagnetic core such that current flowing in the windings magnetizes the ferromagnetic core; and a superconducting film (60, 80, 82) arranged to support eddy current cancelling supercurrent that suppresses eddy current formation in the ferromagnetic core when the windings magnetize the ferromagnetic core. A magnetic resonance scanner embodiment includes a main magnet (20) generating a static magnetic field and a magnetic field gradient system (30) with a plurality of said electromagnets (34, 50, 60) configured to superimpose selected magnetic field gradients on the static magnetic field.
摘要:
A transmission cable for use in an elongate medical device (420) such as a catheter, guide wire, etc., wherein the transmission cable is capable of being switched to an MR-safe mode only when necessary, while retaining its optimal electrical transmission properties otherwise, is disclosed herein. The transmission cable comprises a transmission line including at least two electrically conductive line segments (104a, 104b) separated by a non-conductive gap (106a), a bridging unit comprising at least one electrically conductive bridge segment (108a) capable of bridging the non-conductive gap, and a switching unit (112) arranged to move the bridging unit and/or the transmission line to electrically connect the two line segments by closing the non-conductive gap using the bridge segment or to electrically disconnect the two line segments by opening the non-conductive gap.
摘要:
The present invention relates to a catheter (6) comprising: a connector (65, 66) at a proximal side of the catheter for connecting the catheter to an external signal transmission/receiving unit (10) for transmitting and/or receiving signals, an electrode (63, 64) at a distal side of the catheter, and an electrical connection including an electrical wire (61, 62) for electrically connecting the electrode and the connector for the transmission of signals between the electrode and the connector, wherein the electrical connection has a high electrical resistance of at least 1 kΩ, in particular of at least 5 kΩ. Thus, the present invention provides a solution to prevent excessive heating during EP interventions under MR guidance by using by using highly resistive wires and or lumped resistors as connections within catheters.
摘要:
An electrically conductive transmission cable for supplying a DC signal safely to an electrical device in the presence of radio-frequency (RF) fields in a magnetic resonance (MR) is disclosed herein. The transmission cable comprises a transmission line (STL) comprising at least a first segment (S1) and a second segment (S2), wherein the first and second segments are electrically connected to each other by a reactive coupling unit (103), and a rectifier unit (101) connected to the transmission line and configured to extract the DC signal (203) from the modulated DC signal (201). The extracted DC signal may be supplied to an electrical device or used for cardiac pacing. The transmission cable finds application in auxiliary devices used in an MR environment, for example an interventional catheter with or without an active tracking circuit (301).
摘要:
An electrically conductive transmission line for transmitting RF signals, in particular for transmitting MR signals between a transmission and/or receiving coil and a transmitting and/or receiving unit, by which separate known matching networks can be avoided or reduced. A transmission line is proposed comprising a plurality of lead segments coupled by transformers having a transformer impedance ZL placed between two neighboring lead segments, wherein for power matching of the two transformers placed at opposite ends of a lead segment, the lead segment has a lead segment impedance Z0 or a dielectric constant ∈r and wherein the lead segment has a short length l. Thus, the lead segments themselves provide the matching of the transformers, and separate matching circuits are no longer needed.
摘要:
An electrically conductive transmission cable for supplying a DC signal safely to an electrical device in the presence of radio-frequency (RF) fields in a magnetic resonance (MR) is disclosed herein. The transmission cable comprises a transmission line (STL) comprising at least a first segment (S1) and a second segment (S2), wherein the first and second segments are electrically connected to each other by a reactive coupling unit (103), and a rectifier unit (101) connected to the transmission line and configured to extract the DC signal (203) from the modulated DC signal (201). The extracted DC signal may be supplied to an electrical device or used for cardiac pacing. The transmission cable finds application in auxiliary devices used in an MR environment, for example an interventional catheter with or without an active tracking circuit (301).
摘要:
The present invention relates to a device (100) and method for interfacing a signal transmission/reception device (200) and a catheter (300). A signal transmitted by the signal transmission/reception device (200) and supplied to the device (100) via a first interface (102, 104, 106, 108) can be sensed by a first sensor (114). The sensed signal may be adjusted by an adjustment unit (116). The adjusted signal can be output via a second interface (110, 112) and supplied to the catheter (300). In this way, a resistance loss caused by a conductor (302, 304) of the catheter (300) may be compensated for.