PT - JOURNAL ARTICLE AU - Okamura, Nobuyuki AU - Villemagne, Victor L. AU - Drago, John AU - Pejoska, Svetlana AU - Dhamija, Rajinder K. AU - Mulligan, Rachel S. AU - Ellis, Julia R. AU - Ackermann, Uwe AU - O'Keefe, Graeme AU - Jones, Gareth AU - Kung, Hank F. AU - Pontecorvo, Michael J. AU - Skovronsky, Daniel AU - Rowe, Christopher C. TI - In Vivo Measurement of Vesicular Monoamine Transporter Type 2 Density in Parkinson Disease with <sup>18</sup>F-AV-133 AID - 10.2967/jnumed.109.070094 DP - 2010 Feb 01 TA - Journal of Nuclear Medicine PG - 223--228 VI - 51 IP - 2 4099 - http://jnm.snmjournals.org/content/51/2/223.short 4100 - http://jnm.snmjournals.org/content/51/2/223.full SO - J Nucl Med2010 Feb 01; 51 AB - PET provides a noninvasive means to evaluate the functional integrity of the presynaptic monoaminergic system in the living human brain. Methods: In this study, a novel 18F-labeled tetrabenazine derivative, 18F-(+)fluoropropyldihydrotetrabenazine (18F-AV-133), was used for the noninvasive assessment of the vesicular monoamine transporters type 2 (VMAT2) in 17 Parkinson disease (PD) patients and 6 healthy controls. The binding potential (BP) of 18F-AV-133 was calculated using Logan graphical analysis. Voxel-based and volume-of-interest–based analyses of BP images were performed to examine brain regional reductions in VMAT2 density in PD. Results: VMAT2 BP was decreased by 81% in the posterior putamen, 70% in the anterior putamen, and 48% in the caudate nucleus of PD patients. Voxel-based analysis demonstrated VMAT2 reductions in the striatum and mid brain of PD patients. Furthermore, VMAT2 BPs in the caudate nuclei significantly correlated with the clinical severity of PD. Conclusion: These findings indicate that the novel 18F-labeled ligand 18F-AV-133 can sensitively detect monoaminergic terminal reductions in PD patients. Studies with 18F-AV-133 may allow the presymptomatic identification of individuals with disorders characterized by degeneration of dopaminergic nigrostriatal afferents.