Inveon dedicated pet

A [¹⁸F]-fluorodeoxy-glucose (FDG) reference image was used to evaluate the agent as a diagnostic and therapy follow-up tracer, for each mouse. The mouse was then injected with the imaging and photodynamic therapy bifunctional agent, ¹²⁴I-labeled pyropheophorbide-a derivative. The long half-life of ¹²⁴I (4.2d) allowed for multiple scans of the same mouse and the same agent over time (i.e., a longitudinal study). Tumour uptake relative to the rest of the body increased over time. This result indicated that the agent has therapeutic and tumour-monitoring potential. After FDG incubation, a microPET scanner (Inveon™ Dedicated PET, Siemens) was used to obtain an image of each cervix tumour. Iterative reconstruction and segmented attenuation were used to reconstruct the acquisition data. Standard software (Inveon™ Acquisition workplace) was used for the PET image analyses. Fusion and co-registration of the PET and CT data were performed using a software module. However, the data were manually corrected, if necessary. Volumes of interest were placed around the calcified areas for analysis of fused images.

PET imaging was performed simultaneously in four mice using a Siemens Inveon Dedicated PET (Siemens, Erlangen, Germany) for the [¹⁸F]FLT scans and a Mediso nanoScan PET/CT (Mediso, Münster, Germany) for the [¹⁸F]ML-10 scans. A fifteen-minute transmission scan with an external ⁵⁷Co point source (Siemens Inveon Dedicated PET) or a low-dose CT (Mediso nanoScan PET/CT) served for attenuation correction. The PET data were acquired in 3-dimensional list-mode after 14.5 ± 1.1 MBq of the tracer had been injected into a tail vein. The [¹⁸F]FLT PET was performed 60 to 90 min p.i., the [¹⁸F]ML-10 PET was performed 120 to 150 min p.i. The acquired data were reconstructed with attenuation and scatter correction using the software (Inveon Acquisition Workplace 1.528 Service Pack 1, Nucline NanoScan 3.04.018.0000) and reconstruction algorithms provided by the vendors: ordered subset expectation maximisation algorithm with 4 iterations and 26 subsets (32 MAP iter, pixel size (x, y, z): 0.8, 0.8, 0.8 [mm], matrix size (x, y, z): 128, 128, 159 [mm]) on the Siemens Inveon Dedicated PET and 4 iterations and 6 subsets (pixel size (x, y, z): 0.4, 0.4, 0.4 [mm], matrix size (x, y, z): 212, 212, 239 [mm]) on the Mediso nanoScan PET/CT. Reconstruction parameters for the two devices were chosen for equivalent spatial resolution.