Photon-counting CT enabled clinically acceptable radiotherapy treatment planning for all head-and-neck cancer patients, with dose-volume metrics differing by <5% compared with conventional EID-CT plans.
Relative electron density (RED) images required no scanner-specific calibration, while 70 keV virtual monoenergetic images (VMI70) also provided accurate dose calculations after standard HU-to-RED calibration.
PCCT-derived RED maps demonstrated improved robustness against dental metal artifacts, supporting their use as a quantitative foundation for
radiotherapy planning workflows.
Access publication
Fig. 1. Patient 9 PCD-CT reconstructions. A) Virtual monoenergetic image of 70 keV (VMI70) without iterative metal artifact reduction (iMAR); B) VMI70 with iMAR; C) Relative electron density (RED) image with iMAR. All images shown in the abdomen window (CT values between −125 and 225 HU). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Source: Lamaj E, Wohlfahrt P, Wilke L, et al. Photon-counting detector computed tomography in treatment planning of head-and-neck cancer. Physics and Imaging in Radiation Oncology. 2026;39:100995.
Protocol
Detail | Value |
|---|
Scanner | NAEOTOM Alpha |
Software | VB20 prototype (RED reconstruction) |
Scan area | Head and neck |
Scan mode | Single-source spiral |
Tube voltage [kV] | 120 |
Reconstruction kernel | Qr40 (dose calculation) |
Iterative reconstruction | iMAR (Dental Fillings preset) |
Reconstruction type | Relative Electron Density (RED) map and Virtual Monoenergetic Images (70 keV) |
Spectral reconstruction | RED images (vendor prototype) + 70 keV VMI |
Contrast agent | None |
Patient preparation | Standard radiotherapy simulation |
Treatment planning | Varian Eclipse (Acuros XB), 6 MV VMAT |
Lamaj E, Wohlfahrt P, Wilke L, et al. Photon-counting detector computed tomography in treatment planning of head-and-neck cancer. Physics and Imaging in Radiation Oncology. 2026;39:100995.
