We compared a conventional PET-CT scanner (Siemens Biograph TruePoint TrueV) with and without resolution modelling (RM) image reconstruction with a High Resolution Research Tomograph (HRRT) in order to assess the utility of conventional scanners for brain scanning. A modified Esser phantom and 6 neurofibromatosis 2 (NF2) patients with vestibular schwannomas (VS) were scanned using both scanners. The phantom was filled with fluorine-18 (40 MBq, 4:1 contrast ratio) and scanned for 60 minutes on separate occasions. Patients were injected with ~200 MBq of [18F]fluorodeoxyglucose (FDG) and [18F]fluorothymidine (FLT) on separate occasions and scanned for three consecutive 30 minute periods moving between scanners. The HRRT images, although noisier, resulted in higher contrast recovery for the smallest cylindrical inserts in comparison to TrueV with and without RM. With the TrueV, higher uptake values were observed in VS lesions with both FDG and FLT which is consistent with greater spill-in from the brain for FDG and bone marrow for FLT. RM decreased measured FDG uptake. For large homogenous lesions the conventional TrueV gives similar or better results compared to the HRRT. For smaller lesions, the HRRT has benefit, with RM on the TrueV unable to restore parity, and with the potential for image artefacts.
|Journal||IEEE Transactions on Radiation and Plasma Medical Sciences|
|Early online date||3 May 2019|
|Publication status||Published - 2019|
- Resolution Modelling
- High Resolution PET