| 摘要 |
A system and method for using magnetic resonance to track a medical device which attenuates interfering MR signals. The system comprises an MR tracking device comprising one or more radiofrequency (RF) tracking coils adapted to receive a magnetic resonance MR response signal from nuclei excited by an RF pulse. Ideally, the RF tracking coil only receives an MR response signal from nuclei in matter in the close vicinity of the tracking device. The tracking device is attached to medical device. The interfering signal tends to emanate from large objects or large volumes that are outside the close vicinity of the tracking device but which are still weakly coupled to the tracking device. A dephasing gradient is applied perpendicular to the readout gradient before the RF response signal is received thereby dephasing the interfering signal emanating from remote nuclei, which strongly attenuates the interfering signal while the MR response signal is substantially unaffected. The system can also detect errors in tracking location by checking the amplitude of the signal from each coil and the detected distance between each coil, and correcting for such errors by ignoring data from coils having low amplitude or location deviating from known location relative to the other coils.
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