Abstract:
Apparatus for producing attenuation corrected nuclear medicine images of patients, comprising: at least one gamma camera head that acquires nuclear image data suitable to produce a nuclear tomographic image at a first controllable rotation rate about an axis; at least one X-ray CT imager that acquires X-ray data suitable to produce an attenuation image for correction of the nuclear tomographic image at a second controllable rotation rate about the axis; and a controller that controls the data acquisition and first and second rotation rates to selectively provide at least one of the following modes of operation: (i) a movement gated NM imaging mode in which the second rotation rate is substantially higher than the first rotation rate and the data from each view of the X-ray acquisition is associated with one of a plurality of respiration gated time periods; (ii) a cardiac gated NM imaging mode in which the second rotation rate is substantially higher than the first rotation rate and the data from each view of the X-ray acquisition for different rotations is averaged, wherein the X-ray data is not correlated with the cardiac cycle; and (iii) a cardiac gated NM imaging mode in which the second rotation rate is higher than the first rotation rate and the X-ray data is binned in accordance with a same binning as the NM data.
Abstract:
A method of producing a nuclear medicine image of a subject comprising the steps of acquiring nuclear image data suitable to produce a nuclear tomographic image, the data being acquired by at least one gamma camera head (12, 14) rotating about the subject at an average first rate, acquiring x-ray imaging data suitable to produce an x-ray tomographic image for attenuation correction of the gamma camera image, the data being acquired by an array of detectors (20) irradiated by an x-ray source (18) rotating around the subject at an average second rate which is within a factor of 10 of the first rate, and reconstructing an attenuation corrected nuclear medicine image utilizing the nuclear imaging data and x-ray imaging data.
Abstract:
A nuclear imaging system for imaging of the breast including at least one gamma camera, having a radiation detecting surface, which detects gamma radiation and provides data signals responsive to radiation from the breast and a collimator, positioned over the reception surface. The system includes a gantry on which the radiation detector is mounted and which provides rotational movement of the radiation detection surface around the axis of the breast and a computer which receives and analyzes the data signals and constructs an image of radiation sources therefrom. The radiation detection surface of the at least one gamma camera is tilted with respect to the axis during rotation of the at least one gamma camera about the axis, such that it is partially facing the chest of a study subject. Alternatively, the collimator has septa its center which accept radiation from a direction perpendicular to the radiation detection surface and septa near an edge of the collimator which accept radiation from an outward facing acute angle to the perpendicular direction.
Abstract:
A nuclear medicine camera having an X-ray imaging capability, comprising: a gantry having a stationary portion and at least one rotating portion; at least one gamma camera mounted on a said at least one rotating portion and capable of being rotated together at a common first rotation rate about an axis, said at least one gamma camera being capable of acquiring nuclear imaging data for reconstructing a tomographic nuclear image; and an X-ray CT imager having an X-ray source mounted on said at least one rotating portion and being capable of acquiring X-ray imaging data for reconstructing an X-ray image; said X-ray CT imager being mounted closer to said stationary portion than said at least one gamma camera.
Abstract:
A method of mounting a CT imager on a gantry: determining a center of rotation of a rotor of the gantry; siting a plurality of mounting elements at predetermined positions with respect to the center of rotation; and attaching the mounting elements to the rotor while keeping the mounting elements at the predetermined positions.
Abstract:
A system, for the nuclear imaging of the breast, comprising: at least one gamma camera, of a size appropriate for the scanning of a breast, having a radiation detecting surface, which detects gamma radiation and provides data signals responsive to radiation from the breast; a collimator, positioned over the reception surface; a gantry on which the radiation detector is mounted and which provides rotational movement of the radiation detection surface around the axis of the breast; and a computer which receives and analyzes the data signals and constructs an image of radiation sources therefrom.
Abstract:
A method includes detecting radiation that traverses a material having a known spectral characteristic with a radiation sensitive detector pixel that outputs a signal indicative of the detected radiation and determining a mapping between the output signal and the spectral characteristic. The method further includes determining an energy of a photon detected by the radiation sensitive detector pixel based on a corresponding output of the radiation sensitive detector pixel and the mapping.
Abstract:
A radiation detector (24) includes a two-dimensional array of upper scintillators (30τ) which is disposed facing an x-ray source (14) to convert lower energy radiation into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30τ) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Respective active areas (94, 96) of each upper and lower photodetector arrays (38τ, 38B) are optically coupled to the respective upper and lower scintillators (30τ, 30B) at an inner side (60) of the scintillators (30τ, 30B) which inner side (60) is generally perpendicular to an axial direction (Z). Interference filters (110, 112) may be deposited on the active areas (94, 96) of the associated upper and lower photodetectors (38τ, 38B) to restrict radiation wavelengths received by the upper and lower photodetectors (38τ, 38B) to wavelengths emitted by the respective upper and lower scintillators (30τ, 30B). The upper scintillators (30τ) may include at least one of ZnSe(Te) and YAG(Ce).
Abstract:
A radiation detector (24) includes a two-dimensional array of upper scintillators (30τ) which is disposed facing an x-ray source (14) to convert lower energy radiation into visible light and transmit higher energy radiation. A two-dimensional array of lower scintillators (30B) is disposed adjacent the upper scintillators (30τ) distally from the x-ray source (14) to convert the transmitted higher energy radiation into visible light. Respective active areas (94, 96) of each upper and lower photodetector arrays (38τ, 38B) are optically coupled to the respective upper and lower scintillators (30τ, 30B) at an inner side (60) of the scintillators (30τ, 30B) which inner side (60) is generally perpendicular to an axial direction (Z). Interference filters (110, 112) may be deposited on the active areas (94, 96) of the associated upper and lower photodetectors (38τ, 38B) to restrict radiation wavelengths received by the upper and lower photodetectors (38τ, 38B) to wavelengths emitted by the respective upper and lower scintillators (30τ, 30B). The upper scintillators (30τ) may include at least one of ZnSe(Te) and YAG(Ce).
Abstract:
Low cost large area photodetector arrays are provided. In a first embodiment, the photodetectors comprise an inorganic photoelectric conversion material formed in a single thick layer of material. In a second embodiment, the photodetectors comprise a lamination of several thin layers of an inorganic photoelectric conversion material, the combined thickness of which is large enough to absorb incoming x-rays with a high detector quantum efficiency. In a third embodiment, the photodetectors comprise a lamination of several layers of inorganic or organic photoelectric conversion material, wherein each layer has a composite scintillator coating.