Patent ID: 9151810
Filing Date: 2015-10-06
Classification: A61B,G01R

Abstract:
1. A method for synchronizing a magnetic resonance unit with a cardiac rhythm of a patient, comprising: obtaining electrocardiogram signals of the patient by at least three electrodes respectively, wherein the at least three electrodes are arranged so that the electrocardiogram signals are perpendicular to each other; calculating a three-dimensional vector cardiogram from the electrocardiogram signals, wherein characteristics of the electrocardiogram signals comprise correspondences in loops in the three-dimensional vector cardiogram, generating three two-dimensional vector cardiograms by projecting the three-dimensional vector cardiogram onto three two-dimensional planes; selecting a characteristic of the electrocardiogram signals by selecting a specific loop in the three-dimensional vector cardiogram that is less sensitive to a magnetic field of the magnetic resonance unit than other loops; comparing the electrocardiogram signals obtained before introducing the patient into the magnetic resonance unit and after introducing the patient into the magnetic resonance unit in the three two-dimensional vector cardiograms; selecting a two-dimensional vector cardiogram from the three two-dimensional vector cardiograms having a smallest change based on the comparison, defining a region on the specific loop corresponding to the selected characteristic in the selected two-dimensional vector cardiogram; activating a trigger if a vector moving on the specific loop reaches the region in the selected two-dimensional vector cardiogram; determining a characteristic trigger time within the cardiac rhythm of the patient based on the activation of the trigger; and triggering the magnetic resonance unit based on the characteristic trigger time for synchronizing the magnetic resonance unit with the cardiac rhythm of the patient for a magnetic resonance recording to prevent motion artifacts in different phases within a period motion of heartbeat of the patient.