Individualized Iodine Injection Rates for Coronary Angiography Using Photon-Counting CT

Overview

This study developed and validated a personalized iodine delivery rate (IDR) protocol for coronary CT angiography (cCTA) using photon-counting CT (PCCT). By tailoring contrast injection parameters based on patient body metrics and fixed injection times, the protocol achieved consistent coronary vessel enhancement while minimizing total iodine dose.

Background

Photon-counting CT is an emerging technology in cardiovascular imaging that enables spectral imaging and virtual mono-energetic image reconstruction, improving vessel visualization and plaque quantification. Optimal iodinated contrast media (ICM) injection is critical to achieve target vessel enhancement (350–500 HU) in cCTA. Traditional injection protocols do not account for individual patient characteristics or the capabilities of PCCT, necessitating a personalized approach to iodine delivery rate (IDR) to optimize image quality and reduce iodine load.

Data Highlights

Key Findings

• A personalized formula based on body metrics was successfully developed to calculate iodine delivery rate (IDR) for cCTA on PCCT.
• Fixed injection times with variable injection rates (3.5 vs 5.0 mL/s) combined with personalized contrast dilution achieved consistent coronary enhancement.
• Personalized IDR protocols allowed reduction of total iodine dose while maintaining target vessel enhancement (350–500 HU).
• Use of PCCT and virtual mono-energetic imaging enabled optimization of contrast protocols beyond traditional polychromatic CT constraints.
• No extravasation or adverse events were reported with the personalized injection protocols.

Clinical Implications

Implementing a personalized IDR-based contrast injection protocol in cCTA with PCCT can optimize coronary vessel enhancement while minimizing iodine exposure. Fixed injection times with tailored injection rates and contrast dilution improve consistency across diverse patient body types. This approach supports safer and more effective coronary imaging in clinical practice.

Conclusion

Personalized iodine injection protocols based on patient metrics and fixed injection times on photon-counting CT enable reliable coronary enhancement with reduced iodine load. This method represents a validated strategy to optimize cCTA contrast administration in routine clinical settings.

References

1. University Hospitals Leuven IRB Approvals 2024 -- Study Protocol
2. Siemens Healthineers -- NAEOTOM Alpha.Peak PCCT Scanner Specifications