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Method for rapid MRI needle tracking
Author(s) -
Kochavi Eyal,
Goldsher Dorith,
Azhari Haim
Publication year - 2004
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.20065
Subject(s) - computer science , orientation (vector space) , tracking (education) , computer vision , computation , set (abstract data type) , artificial intelligence , frame (networking) , frame rate , sample (material) , reference frame , mathematics , algorithm , physics , psychology , telecommunications , pedagogy , geometry , thermodynamics , programming language
A new method for MRI needle tracking within a given two‐dimensional (2D) image slice is presented. The method is based on k ‐space investigation of the difference image between the current dynamic frame and a reference frame. Using only a few central k ‐lines of the difference image and a nonlinear optimization procedure, one can resolve the parameters that define the 2D sinc function that best characterizes the needle in k ‐space. The spatial location and orientation of the needle are determined from these parameters. Rapid needle tracking is obtained by repeated acquisitions of the same set of several central k ‐lines (as in a “keyhole” protocol) and repeated computation of these parameters. The calculated needle tip is depicted on the reference image by means of a graphic overlay. The procedure was tested in computer simulations and in actual MRI scans (the computations were done offline). It was demonstrated that six k ‐lines out of 128 usually suffice to locate the needle. The refresh rate of the needle location depends on the time required to sample the subset of k ‐lines, calculate the current needle location, and refresh the reference image. Magn Reson Med 51:1083–1087, 2004. © 2004 Wiley‐Liss, Inc.