Photon-counting CT in the diagnostic workup of OSCC and OPSCC: A prospective evaluation of tumour conspicuity using virtual monoenergetic imaging.

Computed tomography (CT) is an essential tool for staging head and neck cancer. PCCT-detectors can convert the incoming photons directly into electrical signals. This study investigated the potential of PCCT in OSCCs and OPSCCs. The study population comprised 26 patients with an average age of 65.1 years, all of whom were receiving therapy for OSCC (n = 21) or OPSCC (n = 5). PCCT images were analysed using virtual monoenergetic reconstructions (VMIs) with energies ranging from 40 to 100 keV. Blinded VMIs were analysed using a Likert scale. Optimal tumour delineation and image quality were observed at low energies (40-45 keV). Conversely, infiltration into adjacent structures, notably the mandible, was most effectively visualized at an average energy of 80 keV. The effective dose was found to be 1.46 mSv for PCCT representing an almost 50 % reduction compared to conventional CT. However, artefacts caused by metallic restorations remain problematic in PCCT. Nevertheless PCCT has the capacity to enhance soft tissue contrast, thereby facilitating higher spatial resolution and improved diagnostic quality when staging OSCC.