New progress in SPECT/CT quantitative techniques

SPECT has always been considered as a technique that unsuitable be quantitatively analysed. The However, the appearance of such technologies, e.g., as SPECT/CT, physical correction (such as photon attenuation and scattering), and image reconstruction algorithms, haves promoted the development of SPECT/CT quantitative technology development. The direct integration of multiple technologies allows the further improvement of SPECT/CT to further improve performance in image acquisition and processing, thereby ensuring more accurate quantification. The authors mainly summarized the SPECT/CT hardware, physical correction, image reconstruction algorithm, and clinical application and insufficiency. (authors)