RT Journal Article SR Electronic T1 CT Artifact Recognition for the Nuclear Technologist JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 79 OP 81 DO 10.2967/jnmt.107.047431 VO 36 IS 2 A1 Popilock, Robert A1 Sandrasagaren, Kumar A1 Harris, Lowell A1 Kaser, Keith A. YR 2008 UL http://tech.snmjournals.org/content/36/2/79.abstract AB The goal of this article is to make the PET/CT and SPECT/CT operator aware of common artifacts found in CT. In diagnostic imaging, the ability to render an accurate diagnosis requires the technologist to take steps to optimize image quality and recognize when image quality has been compromised—that is, when there is an image artifact. One way these artifacts occur is through the inability of the CT linear attenuation image to precisely represent the linear attenuation map of a 2-dimensional section through the body. The reasons for this inability are multifold. First, CT is subject to the laws of x-ray quantum physics resulting in noise in all CT images. Moreover, all current CT x-ray systems generate a spectrum of energies. Also, CT scanners use detectors of finite dimension, as are the x-ray focal spots; reconstruct images from a finite number of samples distributed over a finite number of views; and acquire the data for each reconstruction over a finite period.