Technical foundations and scanner characteristics of electron beam computed tomography

Purpose: In this review the technical principle and scanner characteristics of electron beam computertomography (EBCT) are discussed. Methods:In contrast to conventional CT, image acquisition in EBCT is achiev ed without mechanically moving parts. This construction allows for short ac quisition times in investigating given anatomical regions (100 ms per slice ) or up to 8 levels without table movement and short interscan delays (50 m s per slice). Results: Depending on the nature of the investigation, the scanner can be u sed in the single slice, continuous volume scanning and multi slice mode. T he single slice mode is used for detection and quantification of coronary c alcifications and for CT angiography of the coronary vessels. Equivalent to the spiral mode in conventional CT, continous volume scanning may be used for routine investigation of the chest and abdomen. Functional investigatio ns of the heart and perfusion measurement of different organs can be perfor med in multi slice mode. Because of the geometry of the electron beam scann er, radiation exposure for certain investigations is above the exposure wit h conventional CT. Conclusion: Future developements will focus on dose efficient radiation col limation, high resolution detector systems and artefact reducing reconstruc tion kernels.