Abstract
PurposeThe aim of this study is to evaluate the impact of different scatter correction strategies on quantification of high-resolution research tomograph (HRRT) data for three tracers covering a wide range in kinetic profiles.ProceduresHealthy subjects received dynamic HRRT scans using either (R)-[11C]verapamil (n = 5), [11C]raclopride (n = 5) or [11C]flumazenil (n = 5). To reduce the effects of patient motion on scatter scaling factors, a margin in the attenuation correction factor (ACF) sinogram was applied prior to 2D or 3D single scatter simulation (SSS).ResultsSome (R)-[11C]verapamil studies showed prominent artefacts that disappeared with an ACF-margin of 10 mm or more. Use of 3D SSS for (R)-[11C]verapamil showed a statistically significant increase in volume of distribution compared with 2D SSS (p < 0.05), but not for [11C]raclopride and [11C]flumazenil studies (p > 0.05).ConclusionsWhen there is a patient motion-induced mismatch between transmission and emission scans, applying an ACF-margin resulted in more reliable scatter scaling factors but did not change (and/or deteriorate) quantification.
Highlights
The high-resolution research tomograph (HRRT; CTI/Siemens, Knoxville, TN, USA) is a dedicated human brain positron emission tomography (PET) scanner that consists of a smaller bore (46.9 cm) and a longer axial field of view (FOV; 25.2 cm) than current commercial Positron emission tomography (PET) scanners [1]
The aim of this study was to evaluate the impact of an attenuation correction factor (ACF)-margin in combination with both 3D and 2D single scatter simulation (SSS) on quantification of HRRT data for three tracers covering a wide range in kinetic profiles, i.e. (R)-[11C]verapamil, [11C]raclopride, a dopamine D2 receptor antagonist, and [11C]flumazenil, an antagonist of the benzodiazepine site of the γ-aminobutyric acid (GABAA)-receptor
When patient motion occurs between transmission and emission data, the observed distribution of volume of distribution (VT) becomes less uniform and deviates from those seen in other (R)-[11C]verapamil brain studies performed on the ECAT EXACT HR+ (CTI/Siemens, Knoxville, TN, USA) [7], a PET scanner that has been extensively studied for its quantitative accuracy and has been widely used for brain PET studies
Summary
The high-resolution research tomograph (HRRT; CTI/Siemens, Knoxville, TN, USA) is a dedicated human brain positron emission tomography (PET) scanner that consists of a smaller bore (46.9 cm) and a longer axial field of view (FOV; 25.2 cm) than current commercial PET scanners [1]. It has a spatial resolution of 2 to 3 mm full width at half maximum (FWHM). 2D SSS was extended to 3D SSS to incorporate scatter coincidences in oblique planes [2]. The impact of 3D SSS on kinetic parameters derived from dynamic brain studies has not been assessed yet
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
