XXII New Patents

specimen can be imaged before and during intrinsic perturbations such as caused by external stimuli or execution of cognitive or motor tasks. Preferably the specimen is perfused with a paramagnetic contrast agent such as Gadolinium or Dysprosium, slowly or by bolus injection, after recording one or more baseline images. The phase angle response of the specimen can then be recorded one or more times as perturbation subsists or as the bolus traverses the area of illumination. Fast Fourier transformation converts gradient spin echo response data to phase angles for a spatial distribution of volume elements in the illuminated slice. The baseline phase angle image is subtracted from the image taken after the bolus injection, providing a high contrast image showing the concentration of the contrast agent. The change Delta phi in phase angle between the images is proportional to the concentration of the contrast agent, enabling accurate measurements of localized blood volume and flow rate. The invention is particularly applicable to visualization of localized ischemia caused by cerebral vascular disease, such as stroke.

5352980

MAGNETIC RESONANCE IMAGING APPARATUS

Machida Yoshio Tochigi, JAPAN Assigned to Kabushiki Kaisha Toshiba

The MR imaging apparatus for imaging a moving spin, comprises a design unit for designing four sets of pulse sequences with four moment vectors,especially four first moment vectors, which can impart a phase shift to the moving spins, an acquiring unit for acquiring echo data by implementing the designed pulse sequences, a calculating unit for calculating a flow-related value of the moving spin, especially, a flow velocity using the echo data and a generating unit for generating image data of the moving spin using the calculated flow velocity. The first moment vectors correspond to four vertices of a tetrahedron respectively located in a 3-D moment space, a center of which coincides with an origin of the 3-D moment space.

5352981

HIGH-RESOLUTION IMAGE RECONSTRUCTION METHOD FOR

MRI

Machida Yoshio Tochigi, JAPAN Assigned to Kabushiki Kaisha Toshiba

In an image reconstruction method for magnetic resonance imaging, an object to be imaged is reconstructed based on Fourier imaging. First, there specified is a spatial resolution smaller than a further spatial resolution under a Nyquist condition derived from the Nyquist theorem. Then, a transformation matrix according to the specified spatial resolution is calculated and an inverse transformation matrix of the calculated transformation matrix is calculated. Then, discrete magnetic resonance signals from the object is collected in accordance with the Fourier imaging. And, discrete oblique Fourier transformation@OFl7 using the inverse transformation matrix is performed on the collected discrete magnetic resonance signals.

5353794

MAGNETIC RESONANCE IMAGING METHOD AND SYSTEM CAPABLE OF MEASURING SHORT

T2 SIGNAL COMPONENTS

Miyazaki Mitsue Tochigiken, JAPAN Assigned to Kabushiki Kaisha Toshiba

A novel spin echo method and system applies a slice-selecting gradient field to a biological body under medical examination located in a static field during which time a spin excitation pulse is also applied to the biological body. A refocusing pulse is applied to the biological body after the application of the slice-selecting gradient field. A rephasing gradient field having the same polarity as the slice-selecting gradient field is applied just after the application of the refocusing pulse. A spin echo signal induced in a slice of the biological body excited by the spin excitation pulse is acquired to obtain MR information of the excited slice. The method reduces echo time and minimizes loss in ‘I2 signal component. A magnetic resonance imaging system for carrying out the method is also disclosed.