Mr imaging with temperature mapping

A magnetic resonance (MR) device comprising at least one main magnet coil for generating a uniform, steady magnetic field within an examination volume, a number of gradient coils for generating switched magnetic field gradients in different spatial directions within the examination volume, at least one RF coil for generating RF pulses within the examination volume and/or for receiving MR signals from an object positioned in the examination volume, a control unit for controlling the temporal succession of RF pulses and switched magnetic field gradients, and a reconstruction unit for reconstructing MR images from the received MR signals, wherein the MR device (1) is arranged to perform the following steps:

• subjecting the object to an imaging sequence of RF pulses and switched magnetic field gradients, which imaging sequence is a stimulated echo sequence including:
• a) at least two preparation RF pulses radiated toward the object during a preparation period, and
• b) one or more reading RF pulses radiated toward the object during an acquisition period temporally subsequent to the preparation period;
• acquiring at least two MR signals during the acquisition period, wherein the two MR signals are either (i) a free induction delay (FID) signal and a conjugate stimulated echo signal or (ii) a stimulated echo signal and a conjugate stimulated echo signal;
• and
• deriving a temperature map indicating the spatial distribution of the temperature within the object from the at least two acquired MR signals.

A computer program to be run on a magnetic resonance (MR) device, which computer program comprises instructions for:

• generating an imaging sequence of RF pulses and switched magnetic field gradients, which imaging sequence is a stimulated echo sequence including:
• a) at least two preparation RF pulses 44 radiated during a preparation period, and
• b) one or more reading RF pulses radiated during an acquisition period temporally subsequent to the preparation period;
• acquiring at least two MR signals during the acquisition period, wherein the two MR signals are either (i) a free induction delay (FID) signal and a conjugate stimulated echo signal or (ii) a stimulated echo signal and a conjugate stimulated echo signal;
• and
• deriving a temperature map indicating the spatial distribution of temperature within an object from the at least two acquired MR signals.