Abstract: This invention relates to methods and apparatus for magnetic resonance (MR) imaging of moving parts of a patient in which flip angles for the excitation of nuclear magnetization are adaptively selected during image data acquisition in order to minimize artifacts. In particular, the flip angles are selected so that a smooth distribution of signal-strengths in k-space results even though the order of phase-encoding gradients is also adaptively selected in dependence of the measured instantaneous state of motion of the moving part. The invention also includes MR apparatus for practicing the described methods and software for controlling an MR apparatus to practice the methods.
Type:
Grant
Filed:
March 28, 2000
Date of Patent:
May 8, 2001
Assignee:
Philips Electronics North America Corporation
Abstract: An MR system for interventional procedures, includes an MR imaging device and an interventional instrument, for example a catheter. The MR device is arranged to acquire images of a part of an object. The entire catheter can be imaged in an MR image by providing a conductor loop which comprises two non-magnetic conductors which are situated at some distance from one another underneath the surface of the catheter, and extend along substantially the entire length of the catheter. Furthermore, the catheter may be provided with a conductor loop and a coil in a location on the catheter. By separate adjustment of the current flowing through the conductor loop and the coil, it is possible to image the location on the catheter with a contrast which deviates from that of the remainder of the catheter.