Patent Number: 
Section: claims

1. A method of adjusting performance of an imaging system, comprising:removing a slit aperture collimator from the imaging system, the imaging system comprising the slit aperture collimator, at least one of a crossed-slit collimator disposed circumferentially about the slit aperture collimator or a septa assembly having one or more septa spaced circumferentially about the slit aperture collimator, and a detector assembly configured to detect collimated gamma rays emanating from a subject in a field of view of the imaging system, wherein the slit aperture collimator is coupled to a collimator support base disposed on a side of the detector assembly, wherein the collimator support base is coupled to a motor to enable rotation of the slit aperture collimator, and wherein the collimator support base is adapted to be moved axially from a region of the imaging system surrounded by the detector assembly;removing either the crossed-slit collimator or the septa assembly from the imaging system; andinserting a pinhole aperture collimator into the imaging system. 2. The method of claim 1, wherein the imaging system comprises a single photon emission computed tomography system or a combined single photon emission computed tomography/x-ray computed tomography system. 3. The method of claim 1, wherein the slit aperture collimator and the pinhole aperture collimator each comprise a radiation absorbent material. 4. The method of claim 1, wherein the imaging system comprises the septa assembly, wherein removing the septa assembly from the imaging system comprises moving the septa assembly in an axial direction. 5. The method of claim 1, wherein removing the slit aperture collimator from the imaging system comprises rotating a collimator support base about an axis, wherein the slit aperture collimator is coupled to the collimator support base. 6. The method of claim 1, wherein the imaging system comprises the crossed-slit collimator, wherein the crossed-slit collimator comprises one or more slit apertures therein, wherein the one or more slit apertures in the crossed-slit collimator are generally orthogonal to one or more slit apertures in the slit aperture collimator. 7. A method of adjusting performance of an imaging system, comprising:removing a pinhole aperture collimator from the imaging system, the imaging system comprising the pinhole aperture collimator and a detector assembly configured to detect collimated gamma rays emanating from a subject in a field of view of the imaging system;inserting a slit aperture collimator into the imaging system, wherein the slit aperture collimator is coupled to a collimator support base disposed on a side of the detector assembly, wherein the collimator support base is coupled to a motor to enable rotation of the slit aperture collimator, and wherein the collimator support base is adapted to be moved axially from a region of the imaging system surrounded by the detector assembly; andinserting either a septa assembly or a cross-slit collimator into the imaging system, wherein the septa assembly or the cross-slit collimator is disposed circumferentially about the slit aperture collimator. 8. The method of claim 7, wherein the imaging system comprises a single photon emission computed tomography system or a combined single photon emission computed tomography/x-ray computed tomography system. 9. The method of claim 7, wherein the pinhole aperture collimator and the slit aperture collimator each comprise a radiation absorbent material. 10. The method of claim 7 wherein the crossed-slit collimator is inserted into the collimator assembly, wherein the crossed-slit collimator comprises one or more slit apertures therein, wherein the one or more slit apertures in the crossed-slit collimator are generally orthogonal to one or more slit apertures in the slit aperture collimator. 11. An imaging system, comprising:a detector assembly configured to detect collimated gamma rays emanating from a subject in a field of view of the imaging system and generate one or more signals in response to the detected gamma rays;a collimator support base disposed on one side of the detector assembly and configured to interchangeably accept a slit aperture collimator and a pinhole aperture collimator in place of one another; anda septa support assembly disposed on an opposite side of the detector assembly and configured to hold the septa assembly for use with the slit aperture collimator in a position between the field of view of the imaging system and the detector assembly and configured to remove the corresponding septa assembly from the position between the field of view and the detector assembly when the pinhole aperture collimator is mounted to the collimator support base. 12. The imaging system of claim 11, wherein the imaging system comprises a single photon emission computed tomography system or a combined single photon emission computed tomography/x-ray computed tomography system. 13. The imaging system of claim 11, wherein the slit aperture collimator comprises one or more slit apertures that extend in a direction generally parallel, perpendicular, or oblique to a longitudinal axis of the slit aperture collimator. 14. The imaging system of claim 11, wherein the slit aperture collimator comprises one or more slit apertures that are generally orthogonal to the one or more septa of the corresponding septa assembly. 15. The imaging system of claim 11, wherein the slit aperture collimator comprises one or more slit apertures that are generally orthogonal to one or more slit apertures of the corresponding crossed-slit collimator. 16. The imaging system of claim 11, wherein the detector assembly comprises at least one of an array of solid-state detector elements or a scintillator assembly coupled to light sensors. 17. The imaging system of claim 11, comprising:a module configured to receive the one or more signals and to process the one or more signals to generate one or more images; andan image display workstation configured to display the one or more images. 18. The imaging system of claim 11, comprising a support for supporting a subject in the field of view. 19. The imaging system of claim 11, wherein the septa support assembly comprises a septa support arm coupled to the corresponding septa assembly, and a rail, wherein the setpa support arm is slidably coupled to the rail. 20. The imaging system of claim 11, wherein the collimator support base is configured to rotate about an axis for removal of the interchangeable first and second collimators. 21. The imaging system of claim 11, wherein the collimator support base comprises a latch for coupling the collimator support base to a frame of the imaging system.