The application of the axial PET concept to novel imaging scenarios

Hadron-therapy (HT) delivers high dose to the tumor, significantly sparing surrounding healthy tissues. Positron Emission Tomography (PET) can be used to image short-lived positron-emitters, produced by the hadron beam in the patient. PET is nowadays the most assessed imaging technique to monitor HT treatments. The number of positron-emitters produced is much lower than in conventional clinical scenarios, dedicated scanners and acquisition protocols are then required. Sensitivity becomes a crucial parameter since the duration of the acquisition is limited by the beam delivery during treatment (in-beam PET) as well as by the physiological wash-out of the radioisotopes after treatment (in-room PET). AX-PET, a novel PET concept with axially oriented crystals, provides a higher sensitivity almost fully decoupled from its 3D spatial resolution. The flexible design can overcome many of the geometrical constraints imposed by HT monitoring. This work presents a preliminary feasibility study of the application of AX-PET to the HT scenario in in-room modality.