Biograph 64 truepoint pet ct system

All patients underwent whole-body PET/CT scanning using a combined PET/CT in-line system (Biograph 64 TruePoint PET/CT system, Siemens, Erlangen, Germany). Patients were injected intravenously with approximately ~740 MBq to 850MBq of [¹¹C]Acetate based on the patient`s bodyweight, and uptake time was 20 minutes. [¹¹C]Acetate was prepared in-house using a fully automated radiosynthesizer (GE FASTlab^®, GE Healthcare, USA) with dedicated software and single-use cassettes produced under good manufacturing practice (GMP).
A supine PET dataset (4–5 bed positions, 3min/ bed position) from the base of the skull to mid-thigh and a low-dose, unenhanced CT scan (spiral scanning; Sl/pitch 3.0/0.55mm, 120kV, 230mAs) for attenuation correction and image registration was obtained. The PET data was reconstructed using the TRUE-X algorithm with four iterations (21 subsets, 168x168 Gaussian filter, FWHM 3mm).

A combined PET/CT in-line system (Biograph 64 TruePoint PET/CT system, Siemens, Erlangen, Germany) was used to acquire PET images. Patients fasted 6 h before they were injected with approximately 300 MBq [¹⁸F]FDG, depending on the patient’s weight, with an uptake time of 45 min. Blood glucose levels were below 150 mg/dl (8.3 mmol/l) at the time of tracer application. A prone PET dataset of the breasts was acquired and an unenhanced low-dose CT was used for attenuation correction. PET images were reconstructed using the TrueX algorithm (Siemens, Erlangen, Germany), which includes commonly used correction factors, as well as a specific point-spread function correction. Four iterations per 21 subsets were used, with a matrix size of 168 × 168, trans-axial field of view of 605 mm (pixel size, 3.6 mm), and section thickness of 5 mm.

A hybrid PET-CT (computed tomography) (Biograph 64 TruePoint PET/CT system, Siemens, Erlangen/Germany) was used. For [¹⁸F]FDG PET/CT, patients fasted for five hours and blood glucose levels were <150 mg/dl (8.3mmol/l). All patients received a body-weight-adapted injection of approximately 200-350MBq [¹⁸F]FDG and [18F]FMISO on different days. Scanning was started after an uptake time of 60 min for [¹⁸F]FDG and 210-240min for [¹⁸F]FMISO. For both radiotracers, a supine PET dataset of unenhanced CT scans were recorded for attenuation correction. For [¹⁸F]FMISO, the unenhanced CT scans were obtained as low-dose scans. The same imaging and post-recon parameters were used for both PET/CT studies. PET images were reconstructed using the iterative TrueX algorithm, which incorporates a specific correction for the point-spread function in addition to commonly used correction factors [35 (link), 36 (link)]. Four iterations per 21 subsets were used, with a matrix size of 168×168, a trans-axial field of view of 605 mm (pixel size 3.6mm), and a section thickness of 5mm. Further technical details are provided by the manufacturer [37 ].