Abstract: Apparatus and method for mounting on an existing x-ray simulator and calculating a back projected computed tomographic image. The detector array is linear and outputs signals from the photodiodes mounted therein to a preprocessor for smoothing, correcting and filtering and subsequent processing to transform the signal from that produced by an x-ray originating from a fan beam source, e.g., in a polar coordinate system, into the signal which would have been produced by a detector in an array on which a parallel beam is incident on a Cartesian coordinate system. The transformed data is converted to a gray scale value for a picture element having a specific position in the Cartesian coordinate system and output to an appropriate display. Data is taken at each incremental angle as the beam source and detector array rotate around a target object.
Abstract: A method of developing a foreground image from two views of an object, such as orthogonal x-ray views, for the making of a projectable three-dimension image on a computer display monitor superimposed on a background image. The foreground image can be included on the original view of the object or can be separate therefrom or can be represented by digital mathematical expression. The method finds particular application in medical applications such as brachytherapy dosimetry, breast biopsy localizing, and external dosimetry computation for radiotherapy. When used with a dosimetry application, isodose lines can be computed and imaged for various simulated positioning and orientation of the radiation sources and simulated dose sizes.
Abstract: Apparatus and method for mounting on an existing x-ray simulator and calculating a back projected computed tomographic image. The detector array is linear and outputs signals from the photodiodes mounted therein to a preprocessor for smoothing, correcting and filtering and subsequent processing to transform the signal from that produced by an x-ray originating from a fan beam source, e.g., in a polar coordinate system, into the signal which would have been produced by a detector in an array on which a parallel beam is incident on a Cartesian coordinate system. The transformed data is converted to a gray scale value for a picture element having a specific position in the Cartesian coordinate system and output to an appropriate display. Data is taken at each incremental angle as the beam source and detector array rotate around a target object.