PT - JOURNAL ARTICLE AU - Robert M. Kessler AU - John Seibyl AU - Ronald L. Cowan AU - David Zald AU - Jacob S. Young AU - Mohammad Sib Ansari AU - Michael G. Stabin TI - Radiation Dosimetry of <sup>18</sup>F-FPEB in Humans AID - 10.2967/jnumed.113.133843 DP - 2014 Jul 01 TA - Journal of Nuclear Medicine PG - 1119--1121 VI - 55 IP - 7 4099 - http://jnm.snmjournals.org/content/55/7/1119.short 4100 - http://jnm.snmjournals.org/content/55/7/1119.full SO - J Nucl Med2014 Jul 01; 55 AB - 18F-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile (18F-FPEB) is a potent and specific radioligand for the metabotropic glutamate receptor subtype 5 (mGluR5). Before undertaking clinical research studies with 18F-FPEB, we performed studies of human radiation dosimetry. Methods: Serial whole-body scans were obtained in 9 healthy human subjects (5 men, 4 women) for 190–440 min after the intravenous administration of 18F-FPEB. Radiation doses were estimated using the OLINDA/EXM software. Results: Peak organ doses were to the urinary bladder wall, 0.258 mGy/MBq (0.955 rad/mCi), and gallbladder wall, 0.193 mGy/MBq (0.716 rad/mCi). The effective dose was 0.025 mSv/MBq (0.0922 rem/mCi). The doses to the red marrow and spleen were 0.00797 mGy/MBq (0.0295 rad/mCi) and 0.00709 mGy/MBq (0.0262 rad/mCi), respectively. Reducing the urinary voiding interval to 60 or 90 min lowered the urinary bladder wall dose to 0.0885 mGy/MBq (0.327 rad/mCi) or 0.128 mGy/MBq (0.473 rad/mCi), respectively, and the effective dose to 0.0149 mSv/MBq (0.0551 rem/mCi) or 0.0171 mSv/MBq (0.0634 rem/mCi), respectively. Conclusion: Urinary voiding should be performed during 18F-FPEB studies to minimize radiation exposure to research subjects.