Positron
Emission Tomography
Imaging
Facilities
and Equipment
The
rodent PET imager
is GE eXplore Vista DR small
animal PET scanner that is located in the IVISR in the Moores Cancer
Center. It is
designed to
accurately quantify and visualize regional, time-varying distributions
of
positron-labeled radiopharmaceuticals. The ring-type gantry
with an aperture
diameter of 8 cm and effective transverse field-of-view of 6 x 4.6 cm
is
designed for mice and rats. The scanner is comprised of a
gantry into which an
animal imaging bed is inserted under computer control. The
scanner uses 36
high spatial resolution, dual scintillators, depth-of-interaction
detector
modules resulting in a total of 6084 detector elements, a crystal array
pitch
of 1.55 mm, and 28.8 million lines of coincidence. The system
provides a
central spatial resolution of 1.6 mm (FWHM) and absolute central point
source
sensitivity of 4.0% in the 250-700 keV energy window. The
system software
allows static, dynamic, whole-body, list mode, transmission and blank
acquisitions
in the 3D mode. Image data analysis includes a 3D ROI tool
and multimodality
image viewing.
Service
The strength of PET
imaging is in the relatively
preserved biochemical behavior of positron emitting
radiotracers. In live and
sedated animals, dynamic PET imaging can measure the time-dependent
cross-sectional tissue concentrations of a radiotracer that can then be
used
for kinetic modeling. Static PET images can provide tissue
and whole body
biodistribution of radiotracers similar to that of autoradiography. PET
provides an alternative to MR imaging of receptor-based agents where
the high
dose required for adequate MR signal saturates the target. Specific
services
include:
-
Imaging of receptor-targeted
agents and gene reporters;
-
Radiochemistry, tracers and
validation (See Radiochemistry section)
-
Metabolic imaging using F-18
FDG;
-
Measurement of tumor
biochemistry and/or physiology via kinetic
modeling (see Kinetic Modeling section)
