title: Flat-detector computed tomography (FD-CT).
abstract: Flat-panel detectors or, synonymously, flat detectors (FDs) have been developed for use in radiography and fluoroscopy with the defined goal to replace standard X-ray film, film-screen combinations and image intensifiers by an advanced sensor system. FD technology in comparison to X-ray film and image intensifiers offers higher dynamic range, dose reduction, fast digital readout and the possibility for dynamic acquisitions of image series, yet keeping to a compact design. It appeared logical to employ FD designs also for computed tomography (CT) imaging. Respective efforts date back a few years only, but FD-CT has meanwhile become widely accepted for interventional and intra-operative imaging using C-arm systems. FD-CT provides a very efficient way of combining two-dimensional (2D) radiographic or fluoroscopic and 3D CT imaging. In addition, FD technology made its way into a number of dedicated CT scanner developments, such as scanners for the maxillo-facial region or for micro-CT applications. This review focuses on technical and performance issues of FD technology and its full range of applications for CT imaging. A comparison with standard clinical CT is of primary interest. It reveals that FD-CT provides higher spatial resolution, but encompasses a number of disadvantages, such as lower dose efficiency, smaller field of view and lower temporal resolution. FD-CT is not aimed at challenging standard clinical CT as regards to the typical diagnostic examinations; but it has already proven unique for a number of dedicated CT applications, offering distinct practical advantages, above all the availability of immediate CT imaging in the interventional suite or the operating room.
authors.affiliation: Institute of Medical Physics, University of Erlangen-Nuernberg, Henkestr. 91, 91052, Erlangen, Germany. willi.kalender@imp.uni-erlangen.de
authors.forename: Willi A
authors.initials: WA
authors.lastname: Kalender
authors.forename: Yiannis
authors.initials: Y
authors.lastname: Kyriakou
mesh_terms: D000792:Angiography / Q000295:instrumentation* / Q000379:methods; D001940:Breast / Q000473:pathology; D004867:Equipment Design; D005471:Fluoroscopy / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation; D008113:Liver Neoplasms / Q000473:pathology; D015233:Models, Statistical; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000639:trends; D012680:Sensitivity and Specificity; D012886:Skull / Q000473:pathology; D013679:Technology, Radiologic / Q000295:instrumentation; D014963:X-Ray Intensifying Screens