Absolute Quantitation of SPECT Studies

Methods for absolute quantitation of SPECT images provide an estimate of the activity uptakes in various organs and tissues in units of (M)Bq or (m)Ci. However, because tomographic SPECT images generally are hampered by several physical and camera-specific effects, accurate and precise compensation methods are required. The most important effects are (1) photon attenuation in the patient resulting in a reduction of expected acquired count; (2) the contribution of events from photons, scattered in the phantom and the collimator but accepted by the energy window because of a poor energy resolution of the NaI(Tl) crystal; and (3) the effect of the collimator response function that degrades the image quality because of the relatively poor spatial resolution.
Source: Seminars in Nuclear Medicine - Category: Nuclear Medicine Authors: Source Type: research