The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1987
Filed:
Aug. 09, 1985
E Mark Haacke, University Hts., OH (US);
Picker International, Inc., Highland Hts., OH (US);
Abstract
The resonance signals from a magnetic resonance imaging apparatus are discretely sampled. The sampled data are non-uniform in data space due to motion, eddy currents in the magnetic field, inaccurate timing in the application of the gradient magnetic fields, non-uniform sampling of the data, or the like. The discretely sampled data, s(k.sub.x, k.sub.y), is mapped from data space to image space by a generalized transform. The generalized transform, unlike a Fourier transform, concurrently corrects for the non-uniformity as it transforms the non-uniform data space data into image space data with a preselected distribution, e.g. uniform. For a given y position of non-uniformly sampled data s(k,y), the estimated spin density .rho.(x,y) is related to the actual spin density .rho.(x,y) by the equation: ##EQU1## where the matrix A describes the non-uniformity and can be calculated or determined experimentally. When the matrix B=A.sup.-1, the estimated and actual data match. In one embodiment, the generalized transform algorithm is determined by inverting the matrix A and operating on a data matrix therewith.