Dual-source CT: The earliest patented ideas for dual (multi)-source CT were proposed by Siemens in Germany, GE in the US and Philips in the Netherlands. For engineering and technical reasons, only one company, Siemens, has realized this idea into a product, and in November 2005 Siemens officially presented this groundbreaking diagnostic imaging product to the world. Conventional spiral CT, with only one X-ray generation unit and one detector system, can be overwhelming when scanning objects moving at high speeds, such as coronary arteries. Usually, engineers improve the CT’s ability to capture moving objects by accelerating the CT’s rotation speed, but due to the industrial level and the huge centrifugal force generated by the CT’s rotation, the fastest CT can only reach one rotation in 0.27 seconds! The emergence of dual-source CT has completely changed this phenomenon. By having two X-ray bulb systems and two detector systems working simultaneously, the scanning speed is doubled. This increases the “equivalent rotation speed” to 0.165 seconds or 0.15 seconds (depending on the model design). Two X-ray generators and two detector systems are mounted at an angle in the same plane for simultaneous scanning. The two sets of X-ray bulbs can emit both rays of the same voltage and rays of different rays, thus allowing the integration or separation of the data. The two different sets of data have different discriminatory abilities for the same organ and tissue, and the two sets of data with different energies allow the separation of tissue structures that cannot be separated or displayed by ordinary CT. That is, energy imaging. If two sets of data are scanned with the same voltage and current value, the two sets of data can be integrated to quickly obtain the tissue structure pattern of the same area, breaking the speed limit of ordinary CT.