Abstract:
The present invention provides a method and apparatus to enhance the image contrast of a digital image device, while simultaneously compensating for image intensity inhomogeneity, regardless of the source, correcting intensity inhomogeneities, and producing a more uniform image appearance. Also, the image is enhanced through increased contrast, e.g., tissue contrast in a medical image. In the method, the error between the histogram of the spatially-weighted original image and a specified histogram is minimized. The specified histogram may be selected to increase contrast for accentuation, e.g., on localized regions of interest. The weighting is preferably achieved by two-dimensional interpolation of a sparse grid of control points overlaying the image. A sparse grid is used rather than a dense one to compensate for slowly-varying image non-uniformity. Also, sparseness reduces the computational complexity, as the final weight set involves the solution of simultaneous linear equations whose number is the size of the grid.
Abstract:
The present invention provides a method and apparatus to enhance the image contrast of a Magnetic Resonance Imaging (MRI) device while simultaneously compensating for image inhomogeneity, regardless of the source. The method makes no assumptions as to the source of the inhomogeneities, e.g., physical coil characteristics or patient placement. In the method, the error between the histogram of the spatially-weighted original image and a specified histogram is minimized. The specified histogram may be selected to increase tissue contrast generally or to accentuate a particular tissue class. The weighting is achieved by two-dimensional interpolation of a sparse grid of control points overlaying the image. The sparse grid is used rather than a dense one to compensate for the slowly varying image non-uniformity. Also, sparseness reduces the computational complexity as the final weight set involves the solution of simultaneous linear equations whose number is the size of the chosen grid.
Abstract:
Methods, apparatus and systems magnetic resonance imaging. The system may acquire images associated with a target region the body part including the target region moves, using a series of imaging planes correlated with the motion. The images are then displayed in time order sequence to provide a motion picture. The system may also provide for imaging in multiple planes such as mutually-perpendicular planes with rapid and facile switching between these planes. The multi-plane views can be used, for example, to monitor insertion of an instrument into the patient.
Abstract:
A personal computer or “PC” based software control system for a magnetic resonance imaging or “MRI” scanner. The software control system manages various types of MRI scanners without modification of the software control system. The control system manages the scanning process through a device driver interface which abstracts the particulars of the specific hardware used to interface to the magnetic, radio frequency, image display, image acquisition, patient handling and scan control subsystems.
Abstract:
The present invention provides a method and apparatus to enhance the image contrast of a digital image device while simultaneously compensating for image intensity inhomogeneity, regardless of the source. The present invention corrects intensity inhomogeneities producing a more uniform image appearance. Also, the image is enhanced through increased contrast, e.g., tissue contrast in a medical image. The method makes no assumptions as to the source of the inhomogeneities, e.g., physical device characteristics or positioning of the object being imaged. In the method, the error between the histogram of the spatially-weighted original image and a specified histogram is minimized. The specified histogram may be selected to increase contrast generally or particularly for accentuation, e.g., on localized regions of interest. The weighting is preferably achieved by two-dimensional interpolation of a sparse grid of control points overlaying the image. A sparse grid is used rather than a dense one to compensate for slowly-varying image non-uniformity. Also, sparseness reduces the computational complexity, as the final weight set involves the solution of simultaneous linear equations whose number is the size of the chosen grid.
Abstract:
A method and system for correlating slice profiles associated with a series of magnetic resonance images taken at a plurality of positions. The method comprises first positioning a patient in a first position in the imaging volume of the magnet. A scout scan is then acquired. Selection is then made of an anatomical landmark in the scout scan, which will be referred to as an anatomical fiducial. A particular slice, typically one of a stack of slices to be acquired in a subsequent scan, is selected and precisely positioned at the location of the anatomical fiducial in the scout scan. Following completion of the scan, the patient may be repositioned, necessitating a new scout scan to set up parameters for a second scan.
Abstract:
An apparatus and method for joining two MRI image data sets to form a composite image. The images are joined together at one or more places along the common area by processing the first and second image data using the square of the normalized intensity difference between at least one group of pixels in the first image data and another group of pixels in the second image data.
Abstract:
The present invention provides a method and apparatus to enhance the image contrast of a digital image device while simultaneously compensating for image intensity inhomogeneity, regardless of the source. The present invention corrects intensity inhomogeneities producing a more uniform image appearance. Also, the image is enhanced through increased contrast, e.g., tissue contrast in a medical image. The method makes no assumptions as to the source of the inhomogeneities, e.g., physical device characteristics or positioning of the object being imaged. In the method, the error between the histogram of the spatially-weighted original image and a specified histogram is minimized. The specified histogram may be selected to increase contrast generally or particularly for accentuation, e.g., on localized regions of interest. The weighting is preferably achieved by two-dimensional interpolation of a sparse grid of control points overlaying the image. A sparse grid is used rather than a dense one to compensate for slowly-varying image non-uniformity. Also, sparseness reduces the computational complexity, as the final weight set involves the solution of simultaneous linear equations whose number is the size of the chosen grid.
Abstract:
A personal computer or "PC" based software control system for a magnetic resonance imaging or "MRI" scanner. The software control system manages various types of MRI scanners without modification of the software control system. The control system manages the scanning process through a device driver interface which abstracts the particulars of the specific hardware used to interface to the magnetic, radio frequency, image display, image acquisition, patient handling and scan control subsystems.