Photon-counting computed tomography enables low-dose, high-quality abdominal imaging: A comparative study with...

Although photon-counting computed tomography (PCCT) has demonstrated superior dose efficiency and image quality compared with conventional energy-integrating detector computed tomography (EID-CT) in theory and in some clinical fields, systematic evaluations of its performance in abdominal imaging, particularly comprehensive studies incorporating both radiation dose and image quality, remain very limited.

To compare radiation dose and image quality between PCCT and conventional EID-CT in abdominal imaging, and to evaluate the potential of PCCT for low-dose, high-quality clinical applications.

Eighty participants were included, comprising 40 subjects who underwent prospective abdominal PCCT and 40 subjects retrospectively matched who underwent routine abdominal EID-CT. Radiation dose parameters [computed tomography dose index (CTDI_vol), dose-length product, and effective dose] were recorded. Objective image quality was assessed using signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), dose-normalized metrics [SNR/(CTDI_vol)^1/2 and CNR/(CTDI_vol)^1/2], noise ratio, and excellent image index. Subjective image quality was evaluated by two experienced radiologists using a five-point Likert scale. Intergroup comparisons were performed using appropriate parametric or nonparametric statistical tests.

Compared with EID-CT, PCCT achieved an approximate 50% reduction in CTDI_vol, dose-length product, and effective dose (all P < 0.001). PCCT demonstrated significantly higher SNR, CNR, SNR/(CTDI_vol)^1/2, CNR/(CTDI_vol)^1/2, and excellent image index, along with a lower noise ratio, indicating superior noise uniformity (all P < 0.001). Subjective assessment showed that 77.5% of PCCT images were rated as excellent (Likert score = 5), compared with 10.0% in the EID-CT group (P < 0.001).

PCCT provides substantially improved dose efficiency and image quality compared with conventional EID-CT in abdominal imaging, supporting its potential role in low-dose clinical computed tomography protocols.