Image Quality in CT: Challenges and Perspectives

  • Thomas L Toth
Part of the Medical Radiology book series (MEDRAD)


This chapter discusses an overview of the complexities of CT image quality. It focuses primarily on the image quality of conventional CT scanners in common clinical use and includes some references to emerging new technologies and reconstruction methods. A review of the fundamental physics of a CT image is provided along with an explanation of why low kV scanning can be a useful dose reduction strategy if approached cautiously. Measurable image characteristics for spatial resolution, image noise and low contrast detectability are discussed along with a summary of image artifacts. Particular emphasis is given to CT noise and low contrast detectability, since these are the image quality characteristics most influenced by dose usage. Noise and detectability are the essence of the clinical dose dilemma: what do I need to detect and how much dose is necessary to be able to confidently detect its presence or absence?


Spatial Frequency Image Noise Hounsfield Unit Modulation Transfer Function Noise Power Spectrum 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.BostonUSA

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