PET Imaging of Serotonin Transporters with (11C)DASB: Test-Retest Reproducibility Using a Multilinear Reference Tissue Parametric Imaging Method.

摘要

Parametric imaging of serotonin transporters (SERT) with (11)C-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)benzonitrile ([(11)C]DASB) PET is a useful data analysis tool. The purpose of this study was to evaluate the reproducibility of measurements of SERT binding potential (BP) and relative blood flow (R(1)) by a 2-parameter multilinear reference tissue parametric imaging method (MRTM2) for human [(11)C]DASB studies. METHODS: Eight healthy subjects (3 men, 5 women; age, 26 +/- 9 y) underwent 2 [(11)C]DASB PET scans separated by 1 h on the same day (dose, 703 +/- 111 MBq). Parametric images of BP and R(1) were generated by MRTM2 using the cerebellum as a reference region. The k'(2) (clearance rate constant from the reference region) required by MRTM2 was estimated by the 3-parameter MRTM. Reproducibility of BP and R(1) measurements was evaluated by calculating bias (100 x (retest - test/test), variability (SD of the bias), and reliability (intraclass correlation coefficient = rho) for several representative regions of interest (ROIs). BP and R(1) were estimated for ROI time-activity curves fitted by MRTM2 and were compared with those based on the parametric images. RESULTS: The test-retest (0.066 +/- 0.013/0.06 +/- 0.011 min(-1)) MRTM k'(2) reproducibility was excellent with small bias (3%) and variability (6%) and high reliability (0.95). Retest BP values were consistently lower than those of test BP values in all regions (a mean negative bias of approximately 6%; P < 0.001). The test-retest BP variability was relatively small, ranging from 4% to 13%, with rho ranging from 0.44 to 0.85. In contrast to BP, test-retest R(1) values were similar with negligible bias of