Vereos system

In total, 36 PET listmode acquisitions were performed: 26 with the scatter phantom, 5 with the sensitivity analysis, and 5 with point sources for the spatial resolution estimation. All corresponding simulations were performed with the same set of digitizer parameters. Experiments have been done on a Philips Vereos system installed at Nancy University Hospital (Nancy, France). Simulations were conducted on a cluster with Intel Xeon CPU E5-2640 v4 @ 2.40 GHz, with 12 GB memory. The GATE macros used for the simulations are available on the website of the OpenGATE collaboration.

Patient preparation in the PET unit and PET acquisition and reconstructions was performed as per the European Association of Nuclear Medicine (EANM) guidelines for PET tumor imaging [18 (link)], our PET unit being EANM research Ltd. (EARL) accredited since 2015 [19 (link),20 (link)]. ¹⁸F-FDG was injected after the glucose level had been checked to be <200 mg/dL in patients who had been fasting for at least 4 h. Patients were provisionally scanned 60 min after the tracer injection. They were scanned from the base of the skull to mid-thigh with the arms on their sides for upper limb melanoma patients, or whole-body scanned for patients with primary melanoma of the lower limb or in patients with known distal subcutaneous metastases.
Two different PET/CT scanners were used: a Vereos system (Philips Medical Systems. Cleveland OH) and a Biograph TrueV with extended field-of-view (Siemens Medical Solutions, Erlangen, Germany). Details regarding acquisition and reconstruction parameters can be found elsewhere [21 (link)].