Abstract: In order to approximate the gradient magnetic field pulse waveform shape with high accuracy and improve the image quality at the time of imaging cross-section change or oblique imaging, an MRI apparatus of the present invention divides the waveform shape of the gradient magnetic field pulse into a plurality of sections, defines an approximation function for each section, and corrects the k-space coordinates at which the echo signal is arranged using the parameter of the approximation function. In addition, an optimal parameter of the approximation function of the waveform shape of the gradient magnetic field pulse is searched for using the measured signal.

Abstract: In a broadband access network, calls can be kept active even when a telephone network fails. A voice gateway function captures callee telephone number information sent from a caller subscriber telephone to the telephone network and, when the telephone network fails, keeps the call active by retaining the connection between the caller and the callee. Furthermore, when the telephone network fails, the operation mode of the voice gateway and all ONTs is switched from an H.248 gateway mode to an SIP softswitch mode, allowing the voice gateway function to relay communication packets between ONTs and new call connections to be made in the broadband access network.

Abstract: Plural blood vessels different in blood flow velocity are depicted with high image quality in blood vessel imaging using PC-MRA method. For this purpose, the present invention performs a measurement of an echo signal based on application of a positive-polarity flow encode pulse and a measurement of an echo signal based on application of a negative-polarity flow encode pulse on an examinee with each of plural phase encodes while varying the flow encode, and a blood vessel image of the examinee is reconstructed by using the plural echo signals having different flow encode absolute values.

Abstract: A technique is provided to reserve large examination space in the tunnel type MRI apparatus, without increasing production cost nor reducing significantly irradiation efficiency and homogeneity in an irradiation distribution within an imaging region. The present invention provides an RF coil unit in which four partial cylindrical coils are placed with a gap therebetween in the circumferential direction inside a cylindrical RF shield, in such a manner that two pairs of the partial cylindrical coils are opposed to each other, and magnetic fields produced by the individual partial cylindrical coils are combined, thereby producing a circularly polarized wave field or an elliptically polarized wave field.

Abstract: The present invention provides an image processing technique which enables various contrast control, by quantitatively handling a degree of phase enhancement in a contrast control as a post-processing of the image reconstruction. A complex operation is performed on each pixel value of a complex image obtained by an MRI, thereby generating an image with desired contrast. Intensity is controlled by increasing or decreasing the argument of the pixel value of each pixel by a constant amount, and the degree of phase enhancement is controlled by multiplying the phase (argument) of each pixel by a constant.

Abstract: In order to stably obtain an even fat-suppressed image without reduction of an imaging efficiency and without being affected by unevenness of irradiation magnetic field of an RF pulse, when an imaging sequence having a first sequence part for suppressing a signal from a desired component of an examinee by applying a CHESS pulse and a second sequence part for measuring an echo signal from the examinee is repeated, the flip angle of the CHESS pulse is changed at plural times. In the case of multi-slice imaging, the flip angle of the CHESS pulse is changed in at lest two slice imaging.

Abstract: There is provided a technique for securing a comfortable examination space in a tunnel type MRI apparatus without increasing the manufacturing cost of the MRI apparatus and sacrificing performance thereof. In an RF coil provided with a hollow-shaped outer conductive element and a strip-shaped conductive element disposed along the outer conductive element in the axial direction, meander lines constituting the strip-shaped conductive element are disposed at uneven distances from the outer conductive element to secure an internal space. In order to obtain uniform sensitivity at the center of the RF coil, the strip-shaped conductive element is constituted with N of connected meander lines, and length of the strip-shaped conductive element is adjusted so that, in the strip-shaped conductive element resonating at resonance frequency of the antenna, nodes are formed in a number of (M+1)×N?1, wherein M is 0 or a natural number of 1 or larger.

Abstract: There is provided a technique for securing a large examination space in a tunnel type MRI device without inviting increase of manufacturing cost and without significantly reducing irradiation efficiency or uniformity of the irradiation intensity distribution in an imaging region. Between rungs of a partially cylindrical RF coil, which coil corresponds to a cylindrical RF coil of which part is removed, there are disposed half-loops generating magnetic fields, which are synthesized with magnetic fields generated by loops constituted by adjacent rungs of the partially cylindrical RF coil and rings connecting the rungs to generate a circularly polarized or elliptically polarized magnetic field. Further, high-frequency signals of the same reference frequency having a desired amplitude ratio and phase difference are supplied to the partially cylindrical RF coils and half-loops.

Abstract: An MRI apparatus capable of performing a high-speed operation for removing aliasing from the data measured by non-Cartesian imaging in a real space with a small amount of operation is provided. Non-Cartesian data sampling is performed by thinning the number of data by using multiple receiver coils having different sensitivity distribution from each other. Image reconstruction means creates orthogonal data by gridding non-orthogonal data obtained by each receiver coil on a grid having an equal spatial resolution to and a narrower field of view than a target image, subjects it to Fourier transform and creates the first image data containing aliasing components. The second image data is created by using the first image data created for each receiver coil and a sensitivity distribution of each receiver coil.

Abstract: An image with a desired contrast is obtained while suppressing body motion artifacts caused by both random motion and periodic motion of an object. In order to do so, an imaging sequence using a non-Cartesian sampling method is executed so as to synchronize with a biological signal only at the start time and a repetition time (TR), which is an execution interval between shots within the imaging sequence, is maintained. In addition, a time difference between a delay time and a start time of each shot is calculated, and a shot with a predetermined time difference or more is executed again after the TR time.

Abstract: A magnetic resonance imaging device includes a predetermined pulse sequence, the predetermined pulse sequence including an unnecessary material suppressing sequence unit for canceling a signal from an unnecessary material which is not a measurement target and a main imaging sequence unit for measuring a nuclear magnetic resonance signal used to create an image of an examinee. The unnecessary material suppressing sequence unit generates at least two or more high frequency magnetic field pulses so that the longitudinal magnetization of the unnecessary material is made spatially uniform in the imaging space under application of a first high frequency magnetic field pulse in the main imaging sequence unit.

Abstract: In a non-cartesian sampling method, in order to reduce an artifact on an image caused by an error of a gradient magnetic field, data for correcting the error caused by the gradient magnetic field are obtained when data used for image reconstruction are obtained, and the data used for the image reconstruction are corrected by using the obtained data for the correction. In order to obtain the data for correcting the error, a block having plural parallel echo signals is measured.

Abstract: A measuring instrument and a measurement method which measures, using magnetic resonance, images such as a functional image, a morphologic image of an object to be measured eliminate the influences of the moving speed of the object to be measured during moving, thereby obtaining a precise measured image.

Abstract: A magnetic resonance imaging device includes magnetic field generating means and control means for controlling receiving means according to a predetermined pulse sequence, the predetermined pulse sequence including an unnecessary material suppressing sequence unit for canceling a signal from an unnecessary material which is not a measurement target and a main imaging sequence unit for measuring a nuclear magnetic resonance signal used to create an image of an examinee. The unnecessary material suppressing sequence unit generates at least two or more high frequency magnetic field pulses so that the longitudinal magnetization of the unnecessary material is made spatially uniform in the imaging space under application of a first high frequency magnetic field pulse in the main imaging sequence unit.

Abstract: A magnetic resonance imaging device includes control means for controlling receiving means according to a predetermined pulse sequence that includes an unnecessary material suppressing sequence unit for suppressing a signal from an unnecessary material which is not a measurement target, and a main imaging sequence unit for measuring a nuclear magnetic resonance signal used to create an image of an examinee. The unnecessary material suppressing sequence unit generates at least two or more high frequency magnetic field pulses so that the longitudinal magnetization of the unnecessary material is made spatially uniform in the imaging space under application of a first high frequency magnetic field pulse in the main imaging sequence unit.

Abstract: When executing an imaging pulse sequence using a high frequency magnetic field pulse with a partial waveform of a predetermined waveform, an application start time of a slice gradient magnetic field applied simultaneously with the high frequency magnetic field pulse is corrected. Specifically, a magnetic resonance signal for correcting the imaging pulse sequence is acquired by executing a prescan sequence using a high frequency magnetic field pulse with a predetermined waveform, an application start time of a slice selection gradient magnetic field in the imaging pulse sequence is corrected using the magnetic resonance signal for correction, and the imaging pulse sequence is executed by applying the slice selection gradient magnetic field with the corrected application start time.

Abstract: The magnetic resonance imaging apparatus includes a control unit for controlling a pulse sequence that applies an RF magnetic field and a magnetic field gradient to a subject placed in a static magnetic field and detects a magnetic resonance signal generated from the subject, and a calculation unit for processing the signal, and the control unit performs the process including the steps of; (1) obtaining first images at different positions in a first direction, (2) obtaining images after the first images are subjected to correction of brightness distortion, (3) obtaining images after the images as to which the brightness distortion has been corrected are further subjected to correction of positional distortion, and (4) synthesizing by a weighting calculation, overlapping areas of the images, after the positional distortion thereof has been corrected.

Abstract: A magnetic resonance imaging apparatus having control unit for fetching a plurality of image data and obtaining an image by a calculation. The control unit performs an unwrap processing to a plurality of regions for removing a main value of a phase rotation amount so as to obtain a distribution diagram of a phase rotation amount caused by magnetostatic unevenness, obtains a plurality of evaluation values based on the phase value between a plurality of regions, selects a desired evaluation value based on the phase value from the plurality of evaluation values, and adjusts the phase values between the regions in accordance with the desired evaluation value.

Abstract: Disclosed is a magnetic resonance imaging apparatus comprising static magnetic field generation means, gradient magnetic field generation means, high-frequency magnetic field generation means, reception means, signal processing means, and control means which controls the gradient magnetic field generation means, the high-frequency magnetic field generation means, the reception means, and the signal processing means, wherein said apparatus comprises: approximation means that approximates the output error of the gradient magnetic field using a combination of multiple parameter values with respect to each direction of the gradient magnetic field; evaluation means that evaluates the combinations of multiple parameter values based on the image quality of a magnetic resonance image that is reconstructed while taking into account the output error of the gradient magnetic field that has been approximated by the approximation means; and determination means that, based on the result of the evaluation by the evaluation

Abstract: A magnetic resonance imaging apparatus is configured to generate a correcting magnetic field for correcting a static magnetic field, based on a first set of information representing an inhomogeneous distribution of the static magnetic field generated depending on the characteristic of the static magnetic field generating means, a second set of information representing an inhomogeneous distribution of the static magnetic field generated depending on the tissue of the object, a third set of information corresponding to a set field of view for imaging in a desired region of the object.