Abstract: A computer-implemented method for operating a magnetic resonance facility is provided. For thermal monitoring of an imaging component that is arranged close to a patient during an examination procedure, a monitoring value of a parameter that influences a temperature of the imaging component is ascertained in a monitoring monitor over a predefined period and is compared with a threshold value. At least one course of action is triggered when the threshold value is overshot. A plurality of monitoring monitors with different threshold values, respectively, is used for different periods.

Abstract: A method performed by an MRI system includes: receiving at least one object parameter value of an object to be examined in accordance with a predefined MRI protocol; determining a frequency distribution of deposition values of examined objects, each having the at least one object parameter value, from available MRI examination datasets; determining, by a control unit of the MRI system, a reference deposition value of the examined objects, each having the at least one object parameter value, from the frequency distribution of the deposition values of the examined objects, each having the at least one object parameter value, for a predefined reference proportion in accordance with a predefined reference determining procedure; and determining, as a function of the reference deposition value, at least one MRI protocol parameter of the predefined MRI protocol for examining the object to be examined, in accordance with a predefined MRI protocol optimization procedure.

Abstract: A method for control of a radio-frequency amplifier of a magnetic resonance system is provided. The method includes determining a radio-frequency power to be output by the radio-frequency amplifier during an examination of a patient in the magnetic resonance system. Using a Lambert W function, a maximum temperature in tissue of the patient is determined as a function of the radio-frequency power. The radio-frequency amplifier is set as a function of the maximum temperature.

Abstract: The present disclosure relates to a method for a magnetic resonance system to protect a patient from being damaged by irradiated radio frequency power. In the method, amount information about maximum energy is determined as a function of a damage model for a patient to be examined with the magnetic resonance system. The maximum energy indicates the maximum radio frequency energy that may be radiated into the patient during the examination of the patient. Furthermore, an amount of energy emitted by a radio frequency amplifier of the magnetic resonance system during the examination of the patient in the magnetic resonance system is determined, and the radio frequency amplifier is adjusted as a function of a comparison of the amount information with the amount of energy emitted by the radio frequency amplifier.

Abstract: The disclosure relates to a method for monitoring an absorption rate when using a primary coil of a magnetic resonance device and a secondary coil inductively coupled to the primary coil and to a monitoring unit, a magnetic resonance device and a computer program product. According to the method a maximum admissible absorption rate is provided, using which a maximum admissible B1 field strength of the secondary coil is determined. Furthermore, an actual B1 field strength of the secondary coil is determined. The absorption rate is monitored using the actual B1 field strength of the secondary coil and the maximum admissible B1 field strength of the secondary coil.

Abstract: A method for verifying at least one default value for a magnetic resonance examination, a verifying unit, a magnetic resonance device and a computer program product are provided. According to the method, at least one default value for an electromagnetic property and a sequence segment are sent to a verifying unit. The verifying unit uses the sequence segment to determine at least one electromagnetic property. The at least one default value is verified by the verifying unit with respect to the at least one electromagnetic property.

Abstract: The disclosure relates to simulating an electrical stimulation during an examination of an examination object, in which the examination object is examined in a MR system to create a MR image using an imaging sequence, where a time characteristic of at least one magnetic field gradient used during the imaging sequence is determined, a time derivative of the time characteristic of the at least one magnetic field gradient is determined, and change time points at which the value of the time derivative changes are determined. The simulation of the electrical stimulation for the imaging sequence is performed, wherein the simulation is restricted to the determined change time points.

Abstract: A method for control of a radio-frequency amplifier of a magnetic resonance system is provided. The method includes determining a radio-frequency power to be output by the radio-frequency amplifier during an examination of a patient in the magnetic resonance system. Using a Lambert W function, a maximum temperature in tissue of the patient is determined as a function of the radio-frequency power. The radio-frequency amplifier is set as a function of the maximum temperature.

Abstract: A method for determining a position of a mobile device relative to a B0 field magnet along a z-coordinate axis, and a device and a magnetic resonance tomography unit for performing the method are provided. The device includes a magnetic field strength sensor arranged in a fixed relative position. A characteristic magnetic field strength Bref of the B0 field magnet that emerges for a plurality of x-y coordinate pairs with a same reference z-coordinate zref is ascertained. The device is moved along the z-coordinate axis until the magnetic field strength sensor measures the characteristic magnetic field strength Bref.

Abstract: A method for operating a temperature control apparatus for a medical examination device, in particular a magnetic resonance apparatus, wherein the medical examination device causes a heat input into the body of a patient to be examined during an examination procedure, and wherein the temperature control apparatus has at least one temperature modifier designed for controlling the temperature of the patient, at least one item of heat information that describes the heat balance of the patient is determined, in order to determine a control parameter for controlling at least one ambient parameter that describes the at least one temperature modifier by taking into account at least one ambient condition on the body of the patient, and at least one examination parameter that describes the examination procedure as the input variables of a heat balance model.

Abstract: The present disclosure relates to a method for a magnetic resonance system to protect a patient from being damaged by irradiated radio frequency power. In the method, amount information about maximum energy is determined as a function of a damage model for a patient to be examined with the magnetic resonance system. The maximum energy indicates the maximum radio frequency energy that may be radiated into the patient during the examination of the patient. Furthermore, an amount of energy emitted by a radio frequency amplifier of the magnetic resonance system during the examination of the patient in the magnetic resonance system is determined, and the radio frequency amplifier is adjusted as a function of a comparison of the amount information with the amount of energy emitted by the radio frequency amplifier.

Abstract: The disclosure relates to a method for monitoring an absorption rate when using a primary coil of a magnetic resonance device and a secondary coil inductively coupled to the primary coil and to a monitoring unit, a magnetic resonance device and a computer program product. According to the method a maximum admissible absorption rate is provided, using which a maximum admissible B1 field strength of the secondary coil is determined. Furthermore, an actual B1 field strength of the secondary coil is determined. The absorption rate is monitored using the actual B1 field strength of the secondary coil and the maximum admissible B1 field strength of the secondary coil.

Abstract: The disclosure relates to simulating an electrical stimulation during an examination of an examination object, in which the examination object is examined in a MR system to create a MR image using an imaging sequence, where a time characteristic of at least one magnetic field gradient used during the imaging sequence is determined, a time derivative of the time characteristic of the at least one magnetic field gradient is determined, and change time points at which the value of the time derivative changes are determined. The simulation of the electrical stimulation for the imaging sequence is performed, wherein the simulation is restricted to the determined change time points.

Abstract: A method for determining a position of a mobile device relative to a B0 field magnet along a z-coordinate axis, and a device and a magnetic resonance tomography unit for performing the method are provided. The device includes a magnetic field strength sensor arranged in a fixed relative position. A characteristic magnetic field strength Bref of the B0 field magnet that emerges for a plurality of x-y coordinate pairs with a same reference z-coordinate zref is ascertained. The device is moved along the z-coordinate axis until the magnetic field strength sensor measures the characteristic magnetic field strength Bref.

Abstract: A method for verifying at least one default value for a magnetic resonance examination, a verifying unit, a magnetic resonance device and a computer program product are provided. According to the method, at least one default value for an electromagnetic property and a sequence segment are sent to a verifying unit. The verifying unit uses the sequence segment to determine at least one electromagnetic property. The at least one default value is verified by the verifying unit with respect to the at least one electromagnetic property.

Abstract: A method for operating a temperature control apparatus for a medical examination device, in particular a magnetic resonance apparatus, wherein the medical examination device causes a heat input into the body of a patient to be examined during an examination procedure, and wherein the temperature control apparatus has at least one temperature modifier designed for controlling the temperature of the patient, at least one item of heat information that describes the heat balance of the patient is determined, in order to determine a control parameter for controlling at least one ambient parameter that describes the at least one temperature modifier by taking into account at least one ambient condition on the body of the patient, and at least one examination parameter that describes the examination procedure as the input variables of a heat balance model.

Abstract: A method for monitoring an exposure experienced by a patient during an examination with a magnetic resonance device having a transmitter device is provided. The method includes determining a coil power loss from measured amplitudes and phases of a first measuring device, and determining an overall transmitted power from voltage measurement values of the second measuring device. The method also includes determining a specific absorption rate (SAR) value describing a power entering a patient from the coil power loss and the overall transmitted power and comparing the SAR value with at least one limit value. A transmission operation of the transmitter device is terminated if the at least one limit value is exceeded.

Abstract: A method for monitoring a high-frequency transmit device of a magnetic resonance tomography system with a transmit antenna system having a plurality of transmit channels is provided. A reference transmit signal is output on different transmit channels of the transmit antenna system, respectively, at different time points, and a reference measurement signal induced by the reference transmit signal is measured on at least one of the other transmit channels using a measuring device assigned to the transmit channel. Based on the reference measurement signal, a phase deviation indicator value is determined. The phase deviation indicator value indicates a relative phase deviation between the measuring devices of the transmit channels in question.

Abstract: A method for monitoring a high-frequency transmit device of a magnetic resonance tomography system with a transmit antenna system having a plurality of transmit channels is provided. A reference transmit signal is output on different transmit channels of the transmit antenna system, respectively, at different time points, and a reference measurement signal induced by the reference transmit signal is measured on at least one of the other transmit channels using a measuring device assigned to the transmit channel. Based on the reference measurement signal, a phase deviation indicator value is determined. The phase deviation indicator value indicates a relative phase deviation between the measuring devices of the transmit channels in question.

Abstract: A method for monitoring an exposure experienced by a patient during an examination with a magnetic resonance device having a transmitter device is provided. The method includes determining a coil power loss from measured amplitudes and phases of a first measuring device, and determining an overall transmitted power from voltage measurement values of the second measuring device. The method also includes determining a specific absorption rate (SAR) value describing a power entering a patient from the coil power loss and the overall transmitted power and comparing the SAR value with at least one limit value. A transmission operation of the transmitter device is terminated if the at least one limit value is exceeded.