Method and system for x-ray CT imaging
Methods and systems for performing x-ray computerized tomographic (CT) reconstruction of imaging data on a rotatable portion of the system, such as a ring-shaped rotor. The rotor may include an x-ray source, and x-ray detector system and a processor, coupled to the detector system, for performing tomographic reconstruction of imaging data collected by the detector system.
1. An x-ray CT system, comprising:
a rotor;
a gantry defining a central imaging bore and comprising a housing within which the rotor rotates around the bore;
an x-ray source mounted to the rotor; and
a detector system mounted to the rotor, the detector system comprising:
a detector chassis comprising a rigid frame;
a plurality of detector elements within the detector chassis and arranged on the rigid frame; and
a processing unit located on or in the detector chassis and comprising a plurality of processing cores for performing parallel processing of image data received from the plurality of detector elements to generate a three-dimensional tomographic reconstruction of an object located in the bore.
2. The x-ray CT system of claim 1 , wherein the processing unit comprises a graphics processing unit (GPU).
3. The x-ray CT system of claim 2 , wherein the GPU comprises an internal memory of at least 2 gigabytes and at least 2048 processing cores.
4. The x-ray CT system of claim 1 , wherein the tomographic reconstruction is at least partially generated while the rotor rotates around the bore.
5. The x-ray CT system of claim 1 , further comprising a wireless transmitter coupled to the processing unit that transmits the tomographic reconstruction from the rotor to an entity off the rotor.
6. The x-ray CT system of claim 1 , wherein the detector system comprises a plurality of detector modules arranged on the rigid frame, each detector module including an array of detector elements of the plurality of detector elements and associated electronic components configured to read out image data from the array of detector elements.
7. The x-ray CT system of claim 1 , wherein the plurality of detector modules are connected in series in a daisy-chain configuration.
8. The x-ray CT system of claim 7 , wherein each detector module includes a processor configured with processor-executable instructions to read out image data from the array of detector elements on the module and transmit the image data from the detector module in response to receiving at least one of a clock signal and image data from a preceding detector module of the series of detector modules.
9. The x-ray CT system of claim 8 , wherein the processor of each detector module is configured with processor-executable instructions to combine image data from the detector module with image data received from one or more preceding detector modules of the series of detector modules before transmitting the combined image data from the detector module.
10. The x-ray CT system of claim 9 , wherein the combined image data is transmitted to each subsequent detector module of the series of detector modules for adding additional image data, and the combined image data from all of the detector modules of the series is transmitted to the processing unit of the detector system for generating the tomographic reconstruction.
11. The x-ray CT system of claim 9 , further comprising:
a reference detector comprising a detector element that is positioned to measure a flux of photons emitted by the x-ray source before the photons impinge on the object located within the bore, the reference detector located at least partially outside of the detector system and comprising an electronics module that generates an electronic representation of the measurement of the flux of photons emitted by the x-ray source, wherein the electronic representation of the measurement of the flux of photons is sent to the processing unit in the detector system for use in generating the tomographic reconstruction.
12. The x-ray CT system of claim 11 , wherein the reference detector comprises a housing containing the detector element located proximate to an x-ray beam outlet port of the x-ray source and a fiber optic cable coupled to the detector element to transmit an optical signal from the detector element to the electronics module, wherein the electronics module is located on a temperature-controlled area of the rotor.
13. The x-ray CT system of claim 12 , wherein the electronics module comprises a photodiode that converts the optical signal from the detector element to an electronic signal that is transmitted to the processing unit in the detector system.
14. The x-ray CT system of claim 11 , wherein the reference detector comprises a temperature sensor that generates an electronic signal indicative of a temperature within the x-ray source, wherein the electronic signal indicative of a temperature within the x-ray source is sent to the processing unit in the detector system for use in generating the tomographic reconstruction.
15. A method for generating an x-ray CT reconstruction with an imaging system comprising an x-ray source and a detector system mounted to a rotatable rotor, the method comprising:
generating an electronic representation of image data received at a plurality of detector elements of the detector system while the rotor rotates;
sending the electronic representation of image data to a processing unit located on or in the detector chassis while the rotor rotates;
performing parallel processing of the image data using a plurality of processing cores of the processing unit to generate a three-dimensional tomographic reconstruction; and
transmitting the tomographic reconstruction from the rotor to an entity off the rotor.
16. The method of claim 15 , wherein the processing unit comprises a graphics processing unit (GPU).
17. The method of claim 16 , wherein the GPU comprises an internal memory of at least 2 gigabytes and at least 2048 processing cores.
18. The method of claim 15 , further comprising generating the tomographic reconstruction while the rotor is rotating.