Abstract: In accordance with one aspect of the invention a method and apparatus for utilizing time of flight information to detect motion during a medical imaging acquisition, such as a PET imaging acquisition, is provided. In accordance with another aspect of the invention, a method and apparatus for detecting and correcting for respiratory motion and cardiac motion in medical images, such as PET images, is provided.

Abstract: A method for reconstructing list mode data comprises: reconstructing all list mode data of a list mode data set (30, 160) to generate a first reconstructed image (32, 62); selecting a sub-set of the list mode data set; and reconstructing the sub-set of the list mode data set to generate an enhanced reconstructed image (84, 86). An image generation system comprises: a reconstruction module (24) configured to perform a standard reconstruction of a list mode data set to generate a standard reconstructed image (32, 62); and a re-reconstruction module (24, 70, 80, 82, 150, 152, 154) configured to perform a reconstruction other than the standard reconstruction of at least a portion of the list mode data set to generate an enhanced reconstructed image (84, 86).

Abstract: In accordance with one aspect of the invention a method and apparatus for utilizing time of flight information to detect motion during a medical imaging acquisition, such as a PET imaging acquisition, is provided. In accordance with another aspect of the invention, a method and apparatus for detecting and correcting for respiratory motion and cardiac motion in medical images, such as PET images, is provided.

Abstract: A method for reconstructing list mode data comprises: reconstructing all list mode data of a list mode data set (30, 160) to generate a first reconstructed image (32, 62); selecting a sub-set of the list mode data set; and reconstructing the sub-set of the list mode data set to generate an enhanced reconstructed image (84, 86). An image generation system comprises: a reconstruction module (24) configured to perform a standard reconstruction of a list mode data set to generate a standard reconstructed image (32, 62); and a re-reconstruction module (24, 70, 80, 82, 150, 152, 154) configured to perform a reconstruction other than the standard reconstruction of at least a portion of the list mode data set to generate an enhanced reconstructed image (84, 86).

Abstract: An imaging system comprises: a ring of positron emission tomography (PET) detectors; a PET housing at least partially surrounding the ring of PET detectors and defining a patient aperture of at least 80 cm; a coincidence detection processor or circuitry configured to identify substantially simultaneous 511 keV radiation detection events corresponding to electron-positron annihilation events; and a PET reconstruction processor configured to reconstruct into a PET image the identified substantially simultaneous 511 keV radiation detection events based on lines of response defined by the substantially simultaneous 511 keV radiation detection events.

Abstract: An imaging system comprises: a ring of positron emission tomography (PET) detectors; a PET housing at least partially surrounding the ring of PET detectors and defining a patient aperture of at least 80 cm; a coincidence detection processor or circuitry configured to identify substantially simultaneous 511 keV radiation detection events corresponding to electron-positron annihilation events; and a PET reconstruction processor configured to reconstruct into a PET image the identified substantially simultaneous 511 keV radiation detection events based on lines of response defined by the substantially simultaneous 511 keV radiation detection events.

Abstract: A nuclear medicine imaging device includes a plurality of detector heads (10) mounted to a movable gantry for rotation around an examination region (12). The detector heads (10) include a housing (28) which surrounds a radiation sensitive crystal (26) which converts received radiation events. A positioning mechanism on the gantry maintains a relationship between the detector heads (10) such that the housing for one detector head lies adjacent to and overlaps the housing for another detector head. During an imaging event, the gantry rotates the detector heads (10) about a region of interest (12) while radiation events are sampled. At a predetermined position relative to the area of interest, the overlapping of the detector heads is reversed.

Abstract: Radiation indicative of an object being imaged is detected and a data set indicative of the detected radiation is generated. Negative cells within the data set are located and ordered for processing. A negative cell is selected for processing. A mask region is defined in relation to the selected cell, and positive cells within the mask region are identified. A correction factor is determined, the value of the positive cells is adjusted accordingly. The value of the selected cell is also adjusted so that the count value of the data set remains constant. If the value of the selected cell is still negative, new correction factors are determined and the values of the positive cells and the selected cell are again adjusted. The process is repeated until all of the negative cells within the data set have been processed. An image indicative of the object is then generated.

Abstract: A method of scatter correction for use with gamma cameras includes the steps of detecting and producing a first count value indicative of gamma radiation falling within a first energy range generally associated with a radionuclide photopeak. Gamma radiation falling within second and third energy ranges is also detected and a corresponding count produced. The second and third ranges are above and below the photopeak, respectively. The location of the second and third energy ranges is determined based on the energy resolution of the gamma camera such that a predetermined percentage of the radiation falling within the second and third ranges results from primary radiation. The second and third energy ranges may be located such that they are non-contiguous with the first energy range. Based on the count of radiation falling within the second and third ranges, the scatter radiation falling within the first energy range can be estimated, and the first count value corrected.