The evolution and state-of-the-art principles of multislice computed tomography.
Computed tomography has revolutionized diagnostic radiology with the introduction of spiral CT in the early 1990s, allowing for the first time the acquisition of volume data without the danger of misregistration or double registration of anatomical details. The next revolution occurred in 1998 when all major CT manufacturers introduced multislice CT (MSCT) systems, which typically offered simultaneous acquisition of four slices, providing considerable improvement towards the goal of isotropic three-dimensional imaging. The most recent generation of MSCT systems acquire 64 slices per rotation, enabling a whole body CTA with 1,500 mm scan range and an isotropic resolution of down to 0.4 mm in only 22- 25 s. The tube and the detector measurement system belong to the most important system components of a CT system, having a large influence on system performance. For example, new rotating envelope tube design principles allow for faster rotation times and for double z-sampling techniques in order to increase resolution. The applied dose is ultimately the limiting factor for the improvement of image quality and increase in isotropic resolution. In order to make best diagnostic use of the applied dose, sophisticated dynamic dose adaptation techniques to patient size and geometry have been developed.
Kohl
Gerhard
G
Siemens Medical Solutions, CT, 1 Siemens Street, Forchheim 91301, Germany. gerhard.kohl@siemens.com
D004867:Equipment Design; D006801:Humans; D021621:Imaging, Three-Dimensional; D011829:Radiation Dosage; D013679:Technology, Radiologic; D015898:Tomography Scanners, X-Ray Computed; D036542:Tomography, Spiral Computed