Biograph hirez 16 pet ct

All patients underwent resting dynamic ¹³N-NH₃ and static ¹⁸F-FDG PET studies (Biograph HiRez 16 PET/CT, Siemens, Erlangen, Germany) 1 week before CRT implantation (except for one patient who underwent a ^99mTc-tetrofosmin perfusion scintigraphy). A scout acquisition followed by a low-dose CT (80 kVp, 11 mAs) was performed for optimal patient positioning and subsequent CT-based attenuation correction of the PET emission data.
For ¹³N-NH₃ PET, a 30-min dynamic list-mode acquisition was started together with a slow bolus intravenous administration of 10 MBq/kg ¹³N-NH₃. In case of a 1-day protocol, the ¹³N-NH₃ scan always preceded the ¹⁸F-FDG scan with a minimum interval of 60 min between tracer administrations.
¹⁸F-FDG PET scan was performed using the hyperinsulinemic euglycemic clamp technique in accordance with the method of Lewis et al. [11 (link)]. After reaching a steady-state plasma glucose level, 4.25 MBq/kg ¹⁸F-FDG was administered intravenously and a 40-min acquisition was performed approximately 45 min after tracer administration.

ADNI FDG-PET images were retrieved from the ADNI Laboratory of Neuroimaging (LONI) database in a format under which images had already been preprocessed through coregistration, averaging, and standardization. The detailed procedure can be found at http://adni.loni.usc.edu/methods/pet-analysis/pre-processing/.
DongA University’s SPECT images were acquired as described previously^{45 (link)}. Patients were injected with 925 MBq of Tc-99m-HMPAO at resting state. Brain SPECT images were obtained from patients using a dual-head gamma camera (Multi-SPECT II, ICON, Siemens, USA) equipped with fan-beamcollimator.
HSC’s FDG-PET images were acquired using Siemens Biograph 16 HiRez PET/CT (Siemens Medical Solutions, Knoxville, TN) scanner. Patients were fasted for at least 6 hours before scanning. Patients were injected i.v. with 185 MBq of FDG and a 15-minute static image was acquired starting 40 minutes post-injection. A head CT scan was acquired for attenuation correction purposes.
Asan Medical Center’s FDG-PET images were acquired as described previously^{26 (link),39 (link)}. All subjects fasted for at least 6 h before scanning. A 5-min transmission scan using a ⁶⁸Ge rotating pin source and a 15-min emission scan were acquired on the ECAT HR + scanner (Siemens Medical Systems, Hoffman Estate, IL, USA) at the Asan Medical Center, 40 min after intravenous injection of 370 MBq of FDG.