Patent classifications
G01R33/3614
Single layer magnetic resonance imaging (MRI) transmit/receive (Tx/Rx) radio frequency (RF) coil with induced current failsafe protection
A single-layer magnetic resonance imaging (MRI) radio frequency (RF) coil element configured to operate in a transmit (Tx) mode and a receive (Rx) mode, the coil element comprising: an LC coil and a failsafe circuit electrically connected with the LC coil, where the LC coil, upon resonating with a primary coil of an MRI system, generates a local amplified Tx field based on an induced current generated in the LC coil by inductive coupling between the LC coil and the primary coil, where the failsafe circuit provides, upon injection of a forward DC bias current into the failsafe circuit, a first impedance, and upon the absence of the forward DC bias current, a second, higher impedance; where the failsafe circuit, upon the single-layer MRI RF coil array element being disconnected from an MRI system, provides the second, higher impedance, and reduces the magnitude of the induced current.
Single-stage amplifier with active feedback compensation
A single-stage radio frequency amplifier is provided with a signal amplification stage for a magnetic resonance tomography scanner, for example as a low-noise preamplifier in a local coil. The radio frequency amplifier includes a signal input, a signal amplifier, a signal output of the signal amplifier and a phase shifter. The phase shifter is in signal connection with the signal output and the signal input of the signal amplifier and is configured to couple a predetermined portion of an output signal of the signal amplifier with a predetermined phase shift into the signal input of the signal amplifier.
A METHOD FOR CONFIGURING A RF TRANSMIT ASSEMBLY
The present disclosure relates to a method for configuring a radio frequency, RF, transmit assembly (200) for a magnetic resonance imaging system (300) for acquiring magnetic resonance imaging data from a subject within an imaging zone using an RF pulse sequence, the RF transmit assembly (200) comprising an RF amplifier (215) and a transmit coil (213), wherein the RF transmit assembly (200) is configurable with a set of configuration parameters. The method comprises: providing (3001) operating conditions of the RF transmit assembly, the operating conditions being indicative of at least: a property of the RF pulse sequence and a measurable parameter that influences the RF pulse sequence property when operating the RF transmit assembly using the RF pulse sequence; using (3003) a predefined machine learning model for determining, for the operating conditions, at least part of the set of configuration parameters and associated values; configuring (3005) the RF transmit assembly (200) in accordance with the determined configuration parameters and associated values.
RADIO FREQUENCY POWER AMPLIFIER AND METHOD OF ASSEMBLY THEREOF
Radio frequency amplifier (200) assembly with effective prevention of RF interference. The radio frequency amplifier comprises an electrically conductive housing (301) that defines an enclosed interior of the radio frequency amplifier assembly, an electrically conductive cooling plate (415) disposed inside the electrically conductive housing and having a first side and an opposite second side, the electrically conductive cooling plate being configured to divide the enclosed interior into a first enclosed region (501) and a second enclosed region (503), and a radio frequency signal processing circuit board (223) equipped with a radio frequency signal processing circuit, the radio frequency signal processing circuit board being positioned in the first enclosed region and disposed on the first side of the electrically conductive cooling plate, and a power supply module and a controller module positioned in the second enclosed region and disposed on the opposite second side of the electrically conductive cooling plate.
Moveable MRI system
Apparatus for imaging during surgical procedures includes an operating room for the surgical procedure and an MRI for obtaining images periodically through the surgical procedure by moving the magnet up to the table. The magnet wire is formed of a superconducting material such as magnesium di-boride or Niobium-Titanium which is cooled by a vacuum cryocooling system to superconductivity without use of liquid helium. The magnet weighs less than 1 to 2 tonne and has a floor area in the range 15 to 35 sq feet so that it can be carried on the floor by a support system having an air cushion covering the base area of the magnet having side skirts so as to spread the weight over the entire base area. The magnet remains in the room during surgery and is powered off to turn off the magnetic field when in the second position remote from the table.
Multi-channel RF transmit system
A multi-channel RF transmit system (1) especially for use in a magnetic resonance examination system comprising, a plurality of RF channels (18, 19) wherein each of the RF channels (18, 19) has an RF amplifier. The multi-channel RF transmit system (1) further comprises a power supply device (2) configured to supply power to the amplifiers (4, 5), a first capacitor bank (6), wherein the first capacitor bank (6) is connected to the power supply device (2) and connected to a first RF amplifier (4), a second capacitor bank (7), wherein the second capacitor bank (7) is connected to the power supply device (2) and connected to a second RF amplifier (5) and a third capacitor bank (8) also connected to the power supply device (2). The third capacitor bank (8) is connected to a DC switch (9), wherein the DC switch (9) is configured to switch the power supplied by the third capacitor bank (8) to the first amplifier (4) or the second amplifier (5). Therefore, a multi-channel RF transmit system (1) is disclosed where parts of the total available capabilities of discrete stored energy can be directed to one or the other RF amplifier channel (18, 19) leading to a more effective and cost saving design of the DC power supply chain.
MR SYSTEM WITH IMPROVED PROTECTION AGAINST CARDIAC STIMULATION
A method for operating an MR system with a gradient power amplifier having at least one output stage that is connectable to a gradient coil, and having four switching elements connected to one another as an H-bridge includes, to operate the gradient coil, in alternation: switching the switching elements attached to a common first pole of a voltage supply to conductive and switching the switching elements attached to a common second pole of a voltage supply to blocking by inverting power drivers; and switching the switching elements attached to a common first pole of a voltage supply to blocking and switching the switching elements attached to a common second pole of a voltage supply to conductive by inverting power drivers. The switching elements attached to the first pole are switched by non-inverting power drivers, and the switching elements attached to the second pole are switched by inverting power drivers.
MAGNETIC RESONANCE APPARATUS WITH A PATIENT VENTILATOR AND A METHOD FOR CONTROLLING A PATIENT VENTILATOR
A magnetic resonance (MR) apparatus may include a patient ventilator, a cooler, and at least one electronic component. The patient ventilator may include at least one airflow generator configured to generate an airflow and at least one ventilation duct. The cooler may be configured to cool the at least one electronic component. The cooler may include at least one cooling element coupled to the patient ventilator.
Mononuclear MRI upgrade system and method
A dual frequency coil package system for use in transmitting and receiving at least two frequencies in an MRI system, including a frequency converter coupled to the MRI system to receive a first frequency through the local transmit coil port and convert the first frequency to a second frequency, a second frequency transmit coil to receive the second frequency from the frequency converter and to transmit the second frequency, a dual tuned receiver coil to receive and to output the at least two frequencies, and a switchable receiver to receive the at least two frequencies output from the dual tuned receiver coil and to transmit the first frequency received from the dual tuned receiver coil directly to the MRI system, and to convert the second frequency received from the dual tuned receiver coil to the first frequency before transmission to the MRI system.
Magnetic resonance imaging apparatus, RF coil, and magnetic resonance imaging method
An MRI apparatus according to an embodiment includes a whole body RF coil accommodated in a gantry. The whole body RF coil includes a first element unit used for transmission of a radio frequency magnetic field; and a second element unit used for reception of a magnetic resonance signal produced from a subject having been applied with the radio frequency magnetic field. The first element unit is a birdcage-type RF coil having two end rings and a plurality of rungs spaced apart from each other along the circumferential direction of the end rings. The second element unit is a microstrip antenna.