Self-Correcting Proton Chemical Shift Imaging With Imperfect Gradients
Original Publication Date: 1986-Feb-01
Included in the Prior Art Database: 2005-Mar-08
Self-correcting proton chemical shift imaging is a method that removes artifacts caused by magnetic field inhomogeneities. The prior-art methods only work when the gradients are perfectly linear. This article describes how to incorporate a priori field mappings of the gradient imperfections into the self-correcting method. The following is an outline for the algorithm. Step 1: Obtain the FIDs (Function Identifications) induced by the pulse-gradient sequence illustrated in Fig. 1. These are to be repeated for r1, r2 chosen that r2 w2 = f, where w2 is the chemical shift of the lipid proton from that of the water proton, and for a one-parameter (discrete) set of values of Gx . The obtained FIDs will be labeled V(r,Gx,t). Step 2: Obtain the FIDs induced by the pulse-gradient sequences illustrated in Fig.