Patent ID: 9345437
Filing Date: 2016-05-24
CPC Classification: A61B,G01R

Claim Text:
1. A method for magnetic resonance (MR) imaging, comprising: using a control computer to operate an MR image data scanner to obtain MR raw data from a subject situated in the MR image data scanner; using said control computer to operate said MR image data scanner, during the acquisition of said MR raw data, to detect respiratory movement of the subject by obtaining a plurality of navigator spirals that comprise MR navigator data representing a series of measurements of respiratory position and phase, including measurement of a current respiratory position, in a respiratory cycle of the subject, with a temporal spacing between successive measurements in said series being small in relation to said respiratory cycle; using said control computer to process said MR navigator data representing said measurements of said respiratory position in said series to assign a status value, among multiple status values respectively designating said phases, to each respiratory position that precedes said current respiratory position; using said control computer to retrieve a momentary status value for the phase for a respiratory position in said series that precedes said current respiratory position; when said series comprises more than two measurements, using said control computer to determine, as of a last change to said momentary status value, a momentarily valid maximum respiratory position or a momentarily valid minimum respiratory position in said series; also when said series comprises more than two measurements, using said control computer to make a comparison, dependent on the momentary status value of the phase of the current respiratory position, with said maximum respiratory position or with said minimum respiratory position, to obtain a comparison result; also when said series comprises more than two measurements, using said control computer to assign a current status value to the respiratory phase of said current respiratory position as occurring during inhalation or exhalation, dependent on said comparison result; when said series comprises two or fewer measurements, using said control computer to assign a current status value of “unknown” to said current respiratory position; using said control computer to apply a prospective gating algorithm to said MR raw data, with an acceptance window in said prospective gating algorithm being determined from said current status value of said current respiratory position; and using said control computer to reconstruct MR image data from said raw data after applying said prospective gating algorithm thereto, and making the MR image data available in electronic form as a data file from said control computer.