Performance evaluation of the PC-2048: a new 15-slice encoded-crystal PET scanner for neurological studies.

Initial experience is reported with the Scanditronix PC 2048-15B, a 15-slice positron emission tomography (PET) system using multicrystal/multiphoto-multiplier modules to obtain high spatial resolution. Random and scattered events are reduced using an orbiting (68)Ge rod source for transmission scans by only accepting coincidence lines which intersect the instantaneous position of the source. Scatter correction of the emission data is removed with a deconvolution kernel, random and dead-time correction by the use of observed singles rates. The peak count rates are 11.7/20.0 Kcps for the direct cross slices at concentrations of 4.5/5.1 muCi/cc. respectively. Over the radial range 0-9 cm from the ring center, radial transverse resolution is 4.6-6.4 mm, aid tangential transverse resolution is 4.6-5.1 mm using a Hanning filter. Over the same range, axial resolution varies from 6.1-6.2 mm in direct slices and from 5.4-7.1 mm in cross slices. This near-isotropic resolution allows collection of image volume data with no preferred direction for signal averaging errors.