To equate the within-subject statistical power across the 2 experiments, each one comprised a total of 44 scans for each stimulus type and an additional 46 silent baseline scans, with the order of conditions randomized.
After cycles 3 and 6, abdomino-pelvic CT scans were performed on patients who had (a) disease evident at baseline and (b) a negative baseline scan with CA-125 evidence of disease progression.
The T1-weighted MRI volume was used to define these regions using the methods described by Riddle et al. 21 Briefly, these anatomical regions were obtained by aligning the subject's T1-weighted MRI volume (acquired at a time point close to the PiB PET baseline scan) with the T1-weighted MRI volume from a reference brain where the regions were segmented manually.
Although all the differences for the SUVs were within ±1.96 SD, the worst agreement for the baseline scans was with SUVmax as shown by greater values for three outcome measures of Bland-Altman analysis, the mean difference and SD, 95% LoA, and CR (Table 1).
For the simulated baseline scans of simulation 2 (BL2), a tumour with heterogeneous FDG uptake was placed within the lungs of the mathematical thorax image, using a tumour (outer rim) to background ratio of 10.
The first baseline scan was acquired with a long TR to ensure complete relaxation of all resonances.
Each baseline scan was paired with a TSPO preblock scan at least 3 h later in the same monkey in which the TSPO ligand 1 (5 mg/kg, i.v). was administered at 15 min before a second injection of the same radioligand (175 253 MBq; carrier dose 3.3 6.7 nmol/kg).
This has the further advantage that the same model can be used in blocking experiments, where baseline scans are compared with scans after administration of a Pgp inhibitor, or when comparing different groups of patients.
For the mouse study, after baseline scans, three mice were infected with an aerosolized respiratory pathogen (necrotic TB) in a Glas-Col inhalation exposure chamber (Glas-Col, Terre Haute, IN, USA) and subsequently imaged on weeks 6, 10, and 14 post-infection or until euthanized for histopathology analysis.
Baseline scans were performed with each radioligand in two (for [C] 7 and [C] 8) or three (for [C] 9) monkeys, one of which, weighing between 10.7 and 11.1 kg, was used in separate sessions for all three radioligands.
