Speaker
Dr
Craig Woody
(Brookhaven National Lab)
Description
A miniature scintillation microprobe has been developed to measure the input function
in live rodents for use in longitudinal, quantitative PET studies. The probe consists
of a small lutetium oxyorthosilicate (LSO) crystal measuring typically 0.3-0.5 mm
diameter x 0.5-2 mm in length that is used to directly detect positrons in the blood
or tissue. The probe has a sensitivity of 10-30 Hz/mCi/cc and is primarily sensitive
to short range positrons emitted by labeled radiotracers in the blood. The
sensitivity to gamma-ray background can be minimized using a variable threshold in
the readout to discriminate between positrons and gammas. The probe was implanted in
one of the tail veins of a Sprague-Dawley rat and the input function was measured for
the injection of 0.8 mCi of FDG in the other tail vein. The probe exhibits a fast
time response that is able to quickly and accurately measure the concentration of 18F
circulating in the bloodstream. Additional tests were also carried out to study the
probe’s sensitivity to gamma ray background.
Author
Dr
Craig Woody
(Brookhaven National Lab)
Co-authors
Dr
David Schlyer
(Brookhaven National Lab)
Dianne Lee
(Brookhaven National Lab)
Dr
Paul Vaska
(Brookhaven National Lab)
Sean Stoll
(Brookhaven National Lab)
Sri Harsha Maramraju
(Stony Brook University)
Dr
Stephen Dewey
(Brookhaven National Lab)
Dr
Wynne Schiffer
(Brookhaven National Lab)