Gemstone Detector: Dual Energy Imaging via Fast kVp Switching

  • Naveen Chandra
  • David A. Langan
Part of the Medical Radiology book series (MEDRAD)


This chapter provides an overview of the GE Discovery CT750HD dual energy imaging capability known as gemstone spectral imaging (GSI). The CT750HD is a single X-ray source system that employs fast kVp switching for dual energy acquisitions. This acquisition method enables precise temporal registration of the dual-energy sinograms, projection-based material decomposition, and delivers a full 50 cm material decomposition scan field of view. The subsystem technologies employed to achieve the dual energy acquisitions are detailed in the discussion of system design. Calibration of fast kVp switching data, material decomposition, and visualization of the resulting images are covered in the image reconstruction and post processing sections. The chapter closes with GSI implementation in the context of challenging diagnostic applications.


Monochromatic Image Mass Attenuation Coefficient Effective Atomic Number Material Decomposition Gemstone Spectral Imaging 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  1. 1.GE HealthcareWaukeshaUSA
  2. 2.GE Global ResearchNiskayunaUSA

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