Abstract: A method of inducing tag lines in an MRI image is provided which allows adjustment of tag line width and spacing. The method includes determining a desired tag line width and then selecting a parameter of a SINC modulating function, such as main lobe bandwidth, in accordance with the desired tag line width. The method also includes determining a desired tag line separation and selecting a parameter of an RF pulse train based upon the desired tag line separation. A gradient field is applied to the specimen being imaged. The RF pulse train is modulated in accordance with the SINC modulating function and the modulated RF pulse train is applied to the specimen being imaged prior to an image acquisition operation. In one embodiment of the invention, the gradient is activated between pulses of the RF pulse train and is deactivated during the RF pulses.
Type:
Grant
Filed:
May 3, 2002
Date of Patent:
August 17, 2004
Assignee:
The Trustees of Columbia University in the City of New
York
Abstract: Apparatus and method for indicating mechanical stiffness properties of body tissue employing Doppler imaging techniques. Ultrasonic signals that are transmitted to the target not only are reflected for developing images of the target from the reflections, but, by appropriate selection of the intensity of the transmitted signals, the body tissue being investigated is deformed or moved when the transmitted signals impinge on the target. The deformation or movement of the body tissue being investigated is imaged and is representative of the mechanical stiffness of this body tissue.
Abstract: An inherently de-coupled sandwiched solenoidal array coil (SSAC) is disclosed for use in receiving nuclear magnetic resonance (NMR) radio frequency (RF) signals in both horizontal and vertical-field magnetic resonance imaging (MRI) systems. In its most basic configuration, the SSAC comprises two coaxial RF receive coils. The first coil of the array has two solenoidal (or loop) sections that are separated from one another along a common axis. The two sections are electrically connected in series but the conductors in each section are wound in opposite directions so that a current through the coil sets up a magnetic field of opposite polarity in each section. The second coil of the SSAC is disposed (“sandwiched”) between the two separated solenoidal sections of the first coil in a region where the combined opposing magnetic fields cancel to become a null.
Type:
Grant
Filed:
August 24, 2001
Date of Patent:
June 15, 2004
Assignee:
Toshiba America MRI, Inc.
Inventors:
Sunyu Su, Leon Kaufman, Mitsuaki Arakawa
Abstract: A medical instrument for treating biological tissue comprises a housing (2), a pressure wave generation means (4) and a transmission means (8) for coupling the unfocused pressure waves into the body of living beings. The transmission means (8) comprises a pressure chamber (12) having an inlet and an outlet end, the pressure chamber (12) containing a liquid (14) into which pressure waves from the pressure wave generation means (4) can be coupled, which pressure waves can be transmitted to a membrane (16) arranged at the outlet end of the pressure chamber (12) which membrane (16) couples the pressure waves transmitted from the liquid unfocusedly into the biological tissue.