Surgery – Diagnostic testing – Detecting nuclear – electromagnetic – or ultrasonic radiation
Reexamination Certificate
2003-04-21
2010-11-16
Casler, Brian (Department: 3737)
Surgery
Diagnostic testing
Detecting nuclear, electromagnetic, or ultrasonic radiation
C600S407000, C600S410000, C324S307000, C324S309000
Reexamination Certificate
active
07835783
ABSTRACT:
Image contributions produced by an untagged specimen magnetization component in magnetic resonance imaging are controlled by applying one or more radiofrequency (RF) pulses that invert at least a portion of the untagged specimen magnetization. In an example, a specimen is tagged with a spatially modulated magnetization that is used to produce an image signal that includes a contribution associated with the tagged magnetization and an untagged magnetization. The untagged magnetization is substantially along an axial direction defined by an applied axial magnetic field. The untagged magnetization increases in magnitude because of so-called T1relaxation. A contribution to the image signal increases for a predetermined time or to a predetermined magnitude, and a 180-degree pulse is applied to invert at least a portion of the untagged magnetization. The untagged magnetization is then antiparallel with respect to the applied axial magnetic field. Additional inversion recovery causes the untagged magnetization to increase from a negative value to zero and then becomes positive. As a result, signal contributions associated with the untagged magnetization are reduced. Additional 180-degree pulses can be applied whenever the untagged magnetization becomes larger than a predetermined value so that image contrast can be maintained. When the tagged magnetization decreases to a predetermined level, an initial specimen magnetization is reestablished for subsequent imaging.
REFERENCES:
patent: 5054489 (1991-10-01), Axel et al.
patent: 5111820 (1992-05-01), Axel et al.
patent: 5217016 (1993-06-01), Axel et al.
patent: 5417214 (1995-05-01), Roberts et al.
patent: 6546274 (2003-04-01), Itagaki et al.
patent: 6721589 (2004-04-01), Zhu et al.
patent: 6892089 (2005-05-01), Prince et al.
patent: 2001/0031037 (2001-10-01), Prince et al.
patent: 0184840 (1989-05-01), None
patent: 0401908 (1996-05-01), None
patent: WO 98/56294 (1998-12-01), None
patent: WO 00/09010 (2000-02-01), None
patent: WO 00/64344 (2000-11-01), None
patent: WO 01/11380 (2001-02-01), None
patent: WO 01/58353 (2001-08-01), None
Aletras et al., “Mixed Echo Train Acquisition Displacement Encoding with Stimulated Echoes: An Optimized Dense Method for In Vivo Functional Imaging of the Human Heart,” Magn. Res. Med. 46:523-534 (2001).
Fischer et al., “Improved Myocardial Tagging Contrast,” Magn. Res. Med. 30:191-200 (1993).
Frangi et al., “Three-Dimensional Modeling for Functional Analysis of Cardiac Images: A Review,” IEEE Trans. Med. Imaging 20:2-25 (2001).
Heiland, “Bewegungsverfolgung des schlagenden Herzens an hyperfein-getaggten, schichtverfolgenden CSPAMM Aufnahmen,” accessed on the Internet Mar. 13, 2002 at mbi.dkfz-heidelberg.de/mbi/sfb414/mot—ana.html.
Kuijer et al., “Improved Harmonic Phase Myocardial Strain Maps,” Magn. Res. Med. 46:993-999 (published online Oct. 18, 2001).
Osman et al., “Cardiac Motion Tracking Using CINE Harmonic Phase (HARP) Magnetic Resonance Imaging,” Magn. Res. Med. 42:1048-1060 (1999).
Stuber et al., “Single Breath-Hold Slice-Following CSPAMM Myocardial Tagging,” MAGMA 9:85-91 (1999).
Casler Brian
Klarquist & Sparkman, LLP
Lamprecht Joel M
The United States of America as represented by the Department of
LandOfFree
Magnetic resonance imaging methods and apparatus for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic resonance imaging methods and apparatus for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic resonance imaging methods and apparatus for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4183169