RT Journal Article SR Electronic T1 Radiation Dosimetry and Biodistribution of the TSPO Ligand 11C-DPA-713 in Humans JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 330 OP 335 DO 10.2967/jnumed.111.094565 VO 53 IS 2 A1 Christopher J. Endres A1 Jennifer M. Coughlin A1 Kenneth L. Gage A1 Crystal C. Watkins A1 Michael Kassiou A1 Martin G. Pomper YR 2012 UL http://jnm.snmjournals.org/content/53/2/330.abstract AB Whole-body PET/CT was used to characterize the radiation dosimetry of 11C-DPA-713, a specific PET ligand for the assessment of translocator protein. Methods: Six healthy control subjects, 3 men and 3 women, underwent whole-body dynamic PET scans after bolus injection of 11C-DPA-713. Subjects were scanned from head to mid thigh with 7 passes performed, with a total PET acquisition of approximately 100 min. Time–activity curves were generated in organs with visible tracer uptake, and tissue residence times were calculated. Whole-body dosimetry was calculated using OLINDA 1.1 software, assuming no voiding. Results: The absorbed dose is highest in the lungs, spleen, kidney, and pancreas. The lungs were determined to be the dose-limiting organ, with an average absorbed dose of 2.01 × 10−2 mSv/MBq (7.43 × 10−2 rem/mCi). On the basis of exposure limits outlined in the U.S. Food and Drug Administration Code of Federal Regulations (21CFR361.1), the single-dose limit for 11C-DPA-713 radiotracer injection is 2,487.6 MBq (67.3 mCi). Conclusion: 11C-DPA-713 has an uptake pattern that is consistent with the biodistribution of translocator protein and yields a dose burden that is comparable to that of other 11C-labeled PET tracers.