Patent ID: 6404196
Filing Date: 2002-06-11
Classification: A61B,G01R

Abstract:
A magnetic resonance imaging system, comprising:means for generating a polarizing magnetic field within an examination region including a subject to be imaged; excitation means for generating an RF excitation magnetic field which produces transverse magnetization in nuclei subjected to the polarizing magnetic field; receiver means for sensing the magnetic resonance signal produced by the transverse magnetization; gradient means for generating a magnetic field gradient to impart a read component into the magnetic resonance signal which is indicative of a location of the transversely magnetized nuclei along a first projection axis, the gradient means generating subsequent magnetic field gradients to impart subsequent read components into the magnetic resonance signal which are indicative of subsequent locations of the transversely magnetized nuclei along subsequent projection axes; pulse control means coupled to the excitation means, the gradient means, and receiver means, said pulse control means being operable to conduct a scan in which a series of data points are acquired at read points along a radial axis to form a magnetic resonance data view, subsequent magnetic resonance data views defining a magnetic resonance data set; and processor means for storing the magnetic resonance data set and for reconstructing an image array for a display from the stored magnetic resonance data set by: a) reconstructing the magnetic resonance data set along the radial axis; b) producing a correction data array including correction values, each of the correction values being calculated as a function of the corresponding stored magnetic resonance datum and the stored magnetic resonance datum for the intersection of the first and subsequent projection axes; c) applying the data in the correction data array to the magnetic resonance data set to produce a final magnetic resonance data set, effects caused by NMR phase inconsistency, including motion of the subject and temporal variations in the polarizing magnetic field being reduced in the final magnetic resonance data set; and d) producing the image array from the final magnetic resonance data set.