Systems and methods for avoiding MRI-originated interference with concurrently used systems
MRI interference with a concurrently operated system may be reduced or corrected by subtracting the MRI interference from signals measured using the concurrently operated system. Various approaches for performing MRI of an anatomic region in conjunction with a radio-frequency-sensitive (RF-sensitive) measurement of the region using a concurrently operated system include the steps of performing an MR scan sequence with the concurrently operated system idle; detecting intervals during the MR scan sequence when an RF level is sufficient to interfere with the RF-sensitive measurement storing data indicative of a temporal extent of the MR scan sequence and the detected intervals; and based at least in part on the stored data, simultaneously performing the scan sequence and operating the concurrently operated system but obtaining the RF-sensitive measurement only during times not corresponding to the recorded intervals.
1. A method of performing magnetic resonance (MR) imaging of an anatomic region in conjunction with radio-frequency-sensitive (RF-sensitive) measurements of the anatomic region using a concurrently operated system, the method comprising the steps of:
with the concurrently operated system idle such that the concurrently operated system is inactive or not performing at least one of its functions but is capable of detecting signals, performing an MR scan sequence including MR pulses;
learning gradient-active intervals of the MR scan sequence by detecting when an RF level during the MR scan sequence would interfere with the RF-sensitive measurements;
storing, in memory, data indicative of a temporal extent of the MR scan sequence and the learned gradient-active intervals; and
retrieving the stored data from the memory and, based at least in part on the retrieved data, simultaneously performing a subsequent MR scan sequence and operating the concurrently operated system without measuring the RF level of the subsequent MR scan sequence;
wherein the RF-sensitive measurements are obtained only during times not corresponding to the gradient-active intervals.
2. The method of claim 1 , wherein the detecting step is performed by the concurrently operated system.
3. The method of claim 1 , wherein the detecting step is performed by at least one dedicated sensor outside the concurrently operated system.
4. The method of claim 1 , further comprising performing the MR scan sequence periodically, wherein the RF-sensitive measurements are performed at least partially in synchronization with at least one of the periodically performed MR scan sequences.
5. A system for performing magnetic resonance (MR) imaging of an anatomic region in conjunction with radio-frequency-sensitive (RF-sensitive) measurements of the anatomic region, the system comprising:
an MR imaging apparatus for imaging the anatomic region;
a concurrently operated system for performing the RF-sensitive measurements; and
a controller in communication with the MR imaging apparatus and the concurrently operated system, the controller being configured to:
with the concurrently operated system idle such that the concurrently operated system is inactive or not performing at least one of its functions but is capable of detecting signals, perform an MR scan sequence including MR pulses;
learn gradient-active intervals of the MR scan sequence by determining when an RF level during the MR scan sequence would interfere with the RF-sensitive measurements;
store, in memory, data indicative of a temporal extent of the MR scan sequence and the learned gradient-active intervals;
retrieve the stored data from the memory and, based at least in part on the retrieved data, simultaneously perform a subsequent MR scan sequence and operate the concurrently operated system without measuring the RF level of the subsequent MR scan sequence;
wherein the RF-sensitive measurements are obtained only during times not corresponding to the gradient-active intervals.
6. The system of claim 5 , wherein the determination of the intervals is performed by the concurrently operated system.
7. The system of claim 5 , wherein the determination of the intervals is performed by at least one dedicated sensor outside the concurrently operated system.
8. The system of claim 5 , wherein the controller is further configured to:
(i) perform the MR scan sequence periodically; and
(ii) perform the RF-sensitive measurements at least partially in synchronization with at least one of the periodically performed MR scan sequences.
9. The system of claim 5 , wherein the concurrently operated system comprises at least one of a phased-array ultrasound transducer system, an ultrasound imaging probe, or a cavitation sensor.