PERFORMANCE-CHARACTERISTICS OF AN 8-RING WHOLE-BODY PET SCANNER

The technical characteristics of the multislice whole-body positron emission tomographic scanner (model PC4096-15WB Scanditronix) and its performance parameters are described. Spatial resolution at the center of the field of view was found to be 4.9 mm in-plane and 4.6 mm (cross slices) and 6.0 mm (direct slices) in the axial direction. The sensitivity for true and scattered coincidences is ~5,000 cps for direct slices and 7,100 cps for cross slices. At an activity concentration of 37 kBq/ml the system deadtime was ~5%. By measuring a uniform phantom with a cold cylindrical insert (5.0 cm diameter), the scatter fraction was found to be ~5%. The mean global uniformity over all 15 slices was 6.5%, whereas the local uniformity was found to be 4.3%. No systematic nonuniformities were observed. Finally, various methods for attenuation correction (transmission scan, contour finding, ellipse) were utilized to test their effects on the resulting reconstructed images. © 1990 Raven Press, Ltd., New York.