Intraindividual Comparison of Photon-Counting Versus Energy-Integrating CT of the Ophthalmic Artery

To conduct an intraindividual comparative analysis of ophthalmic artery imaging quality between photon-counting detector CT (PCD-CT) and energy-integrating detector CT (EID-CT), evaluating both objective and subjective assessments. This retrospective study analyzed patients undergoing carotid artery imaging with both PCD-CT and EID-CT systems. Quantitative analysis involved objective measurements of vascular attenuation (Hounsfield units, HU), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) using standardized region-of-interest (ROI) placements. For qualitative assessment, 2 blinded radiologists independently evaluated subjective image quality through 5-point Likert scales. The cohort [n=26; mean age 65.6±12.6 y; 16 males (61.5%)] demonstrated significantly enhanced performance with PCD-CT. Compared with EID-CT, SNR, CNR, and attenuation values from the PCD-CT system were all significantly higher than values from EID-CT (all P<0.05). Qualitative assessments revealed superior PCD-CT scores across all parameters (all P<0.0001). PCD-CT provides significant improvements in both objective and subjective measurements of ophthalmic artery imaging compared with EID-CT, suggesting its potential as the preferred modality for vascular visualization.