REDUCING INTERFERENCE IN A COMBINED SYSTEM COMPRISING AN MRI SYSTEM AND A NON-MR IMAGING SYSTEM

摘要

The present invention relates to a method and a system for reducing interference between a non-MR imaging system (e.g. a PET imaging scanner) and an MR imaging system. The method comprises receiving at least a signal indicative of the MR RF signal detection period, and in response to the received signal, setting the state of at least a portion of the non-MR imaging system to an inactive state during at least a portion of the MR RF signal detection period.

主权项

1. A method for use in a combined imaging system comprising an MR imaging system with a bore and a PET imaging system;
the MR imaging system having an MR RF signal detection period during which the MR imaging system detects RF signals indicative of the spin of protons within the MR imaging region; and at least a portion of the PET imaging system having an active state and an inactive state; the method comprising the steps of: receiving a signal indicative of the MR RF signal detection period; and either; for the combined imaging system wherein the PET imaging system is fully integrated with the MR imaging system and response to the received signal, setting the state of at least a portion of the PET imaging system to the inactive state during at least a portion of the MR RF signal detection period by switching at least one of the following off: i) the transmission of PET imaging data from within the bore of the MR imaging system to beyond the bore of the MR imaging system; ii) a clock signal controlling a PET imaging data processor within the bore of the MR imaging system; iii) the processing of PET imaging data within the bore of the MR imaging system; iv) the transfer of PET imaging data to a memory within the bore of the MR imaging system; v) the transfer of power from beyond the bore of the MR imaging system to a portion of the PET imaging system within the bore; or, for the combined imaging system wherein the PET imaging system is located close to the MR imaging system and in response to the received signal, setting the state of at least a portion of the PET imaging system to the inactive state during at least a portion of the MR RF signal detection by switching least one of the following of: vi) the generation of timestamps corresponding to the time of detection of gamma photons; vii) the conversion of data from a gamma photon detector in the PET imaging system from analogue data to digital data; viii) the supply of power to at least a portion of the PET imaging system; wherein the signal indicative of the MR RF signal detection period is either: i) generated from a readout gradient field in the MR imaging system by sensing its field using a conductive coil located close to the MR bore; or ii) derived from a detune signal from an MRI RF coil in the MR imaging system.