Single photon-emission computed tomography

• DOI: 10.1007/s12350-010-9246-y
• Publication Date: 2010-06-14T21:03:03Z
• Authors: Thomas A. Holly; Brian G. Abbott; Mouaz Al-Mallah; Dennis A. Calnon; Mylan C. Cohen; Frank P. DiFilippo; Edward P. Ficaro; Michael R. Freeman; Robert C. Hendel; Diwakar Jain; Scott M. Leonard; Kenneth J. Nichols; Donna M. Polk; Prem Soman
• Keywords: Quality Control; Tomography, Emission-Computed, Single-Photon; 03 medical and health sciences; 0302 clinical medicine; Myocardial Perfusion Imaging; Humans

Publisher Summary This chapter discusses single photon emission computed tomography. The development of single photon emission computed tomography (SPECT) put a powerful physiologic imaging technology in the hands of physicians and researchers. SPECT is neither as expensive nor as complex as positron emission tomography (PET) and can be used for many of the same purposes. Cone beam or neurofocal collimation is the most advanced collimator adaptation of the rotating gamma camera to neuro-SPECT. With a two-axis converging collimator rotating about the patient's head, the sensitivity to radiation can be two to four times that of parallel or slant collimators. Resolution approaches 10 mm FWHM. A difficult problem in SPECT imaging is correcting for scatter. The energy window used for photon discrimination includes some off-axis, Comptom-scattered radiation that is back-projected as noise into the reconstructed image along with legitimate, on-axis photons. The deeper inside any scattering material the target image is, the worse the effect is on image resolution. Several schemes are used to compensate for this effect. Labeled-antibody SPECT—with implications for beta and gamma emitter therapy in some cases—is a wide-open field limited only by the nonspecific binding of some antibody preparations. With continuing investigation, more specific agents may become available.