Patent ID: 7505808

Claim:
A method of determining one or both of position and orientation of a medical device in a patient's body, the method comprising the steps of: a) placing the medical device in a patient's body and placing the patient in a magnetic resonance imaging scanner, the magnetic resonance imaging scanner having means for producing magnetic resonance signals having a phase and magnitude and detection means for detecting magnetic resonance signals, and the medical device including at least one marker for perturbing the phase of the magnetic resonance signals; b) acquiring magnetic resonance signals with perturbed phase from the patient's body using the detection means; and c) reconstructing from the acquired magnetic resonance signals with perturbed phase at least one map of a spatial distribution of the phase of the received signals, and using selected characteristics of the spatial distribution of the phase to determine one or both of the device position and orientation of the medical device in the patient's body.