TY - JOUR T1 - Evaluation of the novel glycine transporter 1 (GlyT1) tracer [18F]CFpyPB: Dosimetry and brain quantification in human JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1211 LP - 1211 VL - 50 IS - supplement 2 AU - Sandra Sanabria-Bohorquez AU - Koen Van Laere AU - Terence Hamill AU - Michel Koole AU - G. Bormans AU - Inge De Lepeleire AU - Tom Reynders AU - Cheryl Pickett AU - Anne Van Hecken AU - Donald Burns Y1 - 2009/05/01 UR - http://jnm.snmjournals.org/content/50/supplement_2/1211.abstract N2 - 1211 Objectives [18F]CFpyPB is a potent and selective PET tracer for GlyT1 which has been implicated in schizophrenia pathophysiology. Preliminary human dosimetry and brain tracer kinetics is presented. Methods CFpyPB dosimetry was evaluated in 3 subjects who underwent serial whole-body PET-CT for 6h after bolus injection of 98±3 MBq. Source organs were defined using morphological and functional data. Residence times were derived from time-activity profiles. Individual organ doses and effective doses (ED) were determined using OLINDA/EXM. CFpyPB brain kinetics and test-retest reproducibility was evaluated in 3 additional subjects, two 90 min scans on different days. CFpyPB plasma input function was estimated using total activity counts and relative tracer fraction in arterial plasma. Logan graphical analysis was used to estimate VT. Results Dosimetry estimates resulted in an ED of 24.5 ± 2.9 μSv/MBq. Highest organ doses were observed for lower large intestine (9.1± 2.0 mGy/MBq), ovaries (3.6±0.4 μGy/MBq) and liver (3.0±0.4 μGy/MBq). Rapid brain penetration was observed. The highest CFpyPB uptake was observed in the brain stem (VT=7), followed by cerebellum (VT=6), thalamus and midbrain (VT=5) and white matter (VT=4). Low binding was observed in the cortical gray matter (VT=2). Test-retest variability was below 12%. Conclusions [18F]CFpyPB has an acceptable ED which allows for multiple brain scans of good image quality. [18F]CFpyPB kinetic data can be used to reliably quantify GlyT1 availability in the human brain. ER -