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: In an imaging according to the step moving method, a slice imaging condition with respect to each station is optimized, thereby enabling an efficient imaging. A controller of an MRI apparatus displays positioning frames 601 to 606, and operation handles 607 and 608 thereof, in order to set a slice imaging condition at every various positions (stations) of a table on which a test object is mounted. By manipulating the positioning frames and the operation handles via I/O unit, the slice imaging condition is set. According to this slice imaging condition, imaging at each station position of the table is executed.

Abstract: When performing imaging in synchronization with a biological movement of an examinee by using a pulse sequence applying a pre-saturation pulse, it is possible to reduce irregularities of echo signal intensity and artifact on the image generated by the irregularities. Especially, it is possible to prevent artifact attributed to blood in the ventricle when performing delay contrast imaging. For this, before measuring the echo signal, an IR pulse or the like for adjusting magnetization to a desired state is applied so as to suppress irregularities of the echo signal intensity and prevent artifact.

Abstract: A control means controls an imaging means for taking an image of a test object by a magnetic resonance, the test object being placed in an imaging space, and a transfer means that moves the test object, and on the basis of a difference (moving distance) between a position of the transfer means at the time of receiving a command of pausing the imaging and a position of the transfer means at the time of resuming the imaging, the control means controls the position of the transfer means or the position for imaging at the time of resuming, in such a manner that missing of data 503 caused by the difference can be compensated. With this configuration, it is possible to provide an MRI apparatus that is provided with an imaging pause function, and even when the pause function is activated, there is data consistency between the data before the pausing and the data after the resuming, thereby obtaining a high quality image.

Abstract: In an imaging according to the step moving method, a slice imaging condition with respect to each station is optimized, thereby enabling an efficient imaging. A controller of an MRI apparatus displays positioning frames 601 to 606, and operation handles 607 and 608 thereof, in order to set a slice imaging condition at every various positions (stations) of a table on which a test object is mounted. By manipulating the positioning frames and the operation handles via I/O unit, the slice imaging condition is set. According to this slice imaging condition, imaging at each station position of the table is executed.

Abstract: A control means controls an imaging means for taking an image of a test object by a magnetic resonance, the test object being placed in an imaging space, and a transfer means that moves the test object, and on the basis of a difference (moving distance) between a position of the transfer means at the time of receiving a command of pausing the imaging and a position of the transfer means at the time of resuming the imaging, the control means controls the position of the transfer means or the position for imaging at the time of resuming, in such a manner that missing of data 503 caused by the difference can be compensated. With this configuration, it is possible to provide an MRI apparatus that is provided with an imaging pause function, and even when the pause function is activated, there is data consistency between the data before the pausing and the data after the resuming, thereby obtaining a high quality image.

Abstract: A magnetic resonance imaging method for fully automatically forming a water/fat separated image by calculation after acquiring data on images of different echo times, wherein the unwrapping of a phase map showing the distribution of the phase rotation due to the inhomogeneous static magnetic field is repeated so as to determine the distribution of the inhomogeneous static magnetic field by using an index used for judging whether or not the unwrapping is properly being performed, and wherein during the formation of a water/fat separated image with correction of the static magnetic field, the unwrapping is automatically and properly performed in correcting the static magnetic field, and the water/fat images are automatically discriminated.

Abstract: When performing imaging in synchronization with a biological movement of an examinee by using a pulse sequence applying a pre-saturation pulse, it is possible to reduce irregularities of echo signal intensity and artifact on the image generated by the irregularities. Especially, it is possible to prevent artifact attributed to blood in the ventricle when performing delay contrast imaging. For this, before measuring the echo signal, an IR pulse or the like for adjusting magnetization to a desired state is applied so as to suppress irregularities of the echo signal intensity and prevent artifact.

Abstract: When data of plural original images having different echo times are acquired to produce water/fat separated images by performing an processing operations in an MRI apparatus, a partial region of the original image data is specified and the specified region is subjected to the water/fat separation processing. Since noise components included in the specified region are fewer than those in the original image data, errors occurring due to noise components during unwrapping and other such processing operations can be reduced and image quality degradation be suppressed. Therefore, water/fat separated images having an excellent image quality can be produced. When echoes having different echo times are generated, rewind pulses are applied ahead of the readout gradient magnetic fields to equalize the polarities of the readout gradient magnetic fields. Consequently, influence of application of gradient magnetic fields on echo signals can be suppressed and the accuracy of water/fat separation can be improved.

Abstract: A magnetic resonance imaging apparatus having control means for fetching a plurality of image data and obtaining an image by a calculation. The control means 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 values 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: An imaging sequence for MRI is performed to produce MR images of an object to be examined and display them on a monitor. Marks 6, 7 and 8 are defined at regions to be observed (observation regions), such as a bifurcation 3 and constriction 4 of the displayed image 1. If the distance between an invasive device 10 displayed in the image and the marks is within a predetermined range, at least one of the frame rate (reciprocal of an image-updating interval) and the spatial resolution is altered so as to automatically raise the imaging speed or so as to improve the spatial resolution when the invasive device reaches the observation region. The movement of the invasive device and its relationship to a blood vessel can therefore be finely monitored with high accuracy.

Abstract: In order to improve image quality in MRI using an EPI method without extending imaging time excessively, reference data is acquired in the absence of substantial phase encoding gradients by using an EPI sequence in combination with an echo shift (ETS) method, at times related to the timing of echo signals for image data. The reference data is used for phase correcting the image data acquired with application of phase encoding. The reference data can be measured for a single shot, or a few shots, and used to estimate reference data for the rest of the shots in which imaging data is acquired.

Abstract: When data of plural original images having different echo times are acquired to produce water/fat separated images by performing an processing operations in an MRI apparatus, a partial region of the original image data is specified and the specified region is subjected to the water/fat separation processing. Since noise components included in the specified region are fewer than those in the original image data, errors occurring due to noise components during unwrapping and other such processing operations can be reduced and image quality degradation be suppressed. Therefore, water/fat separated images having an excellent image quality can be produced. When echoes having different echo times are generated, rewind pulses are applied ahead of the readout gradient magnetic fields to equalize the polarities of the readout gradient magnetic fields. Consequently, influence of application of gradient magnetic fields on echo signals can be suppressed and the accuracy of water/fat separation can be improved.

Abstract: A magnetic resonance imaging method for fully automatically forming a water/fat separated image by calculation after acquiring data on images of different echo times, wherein the unwrapping of a phase map showing the distribution of the phase rotation due to the inhomogeneous static magnetic field is repeated so as to determine the distribution of the inhomogeneous static magnetic field by using an index used for judging whether or not the unwrapping is properly being performed, and wherein during the formation of a water/fat separated image with correction of the static magnetic field, the unwrapping is automatically and properly performed in correcting the static magnetic field, and the water/fat images are automatically discriminated.