Fast volume scanning approaches by X-ray-computed tomography

X-ray-computed tomography (CT) successfully underwent a transition from slice-by-slice imaging to volume imaging in the decade after 1990 due to the introduction of spiral scan modes. Later, the transition from single-slice to multislice scanning followed. With the advent of new detector technologies we are now looking forward to circular and spiral scanning using area detectors and the respective reconstruction approaches. This review treats the basic technological and algorithmic prerequisites and approaches. It goes into detail with respect to the achievable performance and image quality characteristics and discusses the range of applications. Scanning of the complete body trunk with submillimeter isotropic resolution in less than 30 s is possible today. Further extensions to new medical applications, for example, cardiac CT, but also to nonmedical applications, for example, nondestructive material testing, make CT an emerging imaging modality again.