Charles William Stearns

Generation of the Acquisition-Specific NEC (AS-NEC) Curves to Optimize the Injected Dose in 3D

Aim of this work was the implementation and validation, for the Discovery-ST PET/CT (GE Medical Systems) system, of the acquisition-specific noise equivalent counts (AS-NEC) method to establish the amount of tracer to be injected in 3D

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F-FDG Whole Body PET Studies

F-FDG whole body (WB) PET studies to achieve the peak of the NEC (NEC-p) at the acquisition time. The AS-NEC method uses prompts, delayed events and detector dead-time of a single reference PET scan to calculate the full shape of the NEC curve. The method was implemented using a 3D decay series of the 70 cm NEMA 2001 (line source in a 20 cm diameter solid polyethylene cylinder) phantom and validated with the cylindrical NEMA 1994 (diameter, 20 cm; length, 20 cm) and NEMA 2001 IEC body phantoms. The NEC curves generated by the single frames of the phantom series, using the AS-NEC method, well correlated with the experimental NEC curves proving the validity of the method and the possible application to clinical studies. The AS-NEC model was then retrospectively applied on 40 3D

Simulation of countrate performance for a PET scanner with different degrees of partial collimation

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NEMA NU2-2001 performance results for the GE advance PET system

F-FDG WB studies in a range of body mass index (BMI) between 16 and 30 (kg/m

Image Reconstruction for a Partially Collimated Whole Body PET Scanner

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Multi modality imaging methods and apparatus

) (6 under-weight (uw), 18 normal-weight (nw), 16 over-weight (ow)). For each acquisition frame of each patient study, the activity at the acquisition time, corresponding to the NEC-p was identified on the NEC curves. Furthermore, as the NEC curves show a region around the NEC-p with small variations (nearly a plateau), the values of radioactivity corresponding to a reduction of 1%, 3% and 5% with respect to NEC-p were also calculated to assess a possible reduction of the doses to be injected in clinical studies. The results show that the average activities at the acquisition time corresponding to the NEC-p were comparable for the three BMI classes: 336.7 MBq

Sorter for coincidence timing calibration in a PET scanner

( sd=22.2), 329.3

Iterative reconstruction of tomographic image data method and system

MBq

Method and apparatus for timing calibration in a PET scanner

( sd=33.3), 344.1