Emerging research demonstrates that cardiac photon-counting computed tomography (PCCT) offers comparable image quality to energy-integrating detector CT (EID CT) and facilitates significantly lower radiation dosing for pediatric patients with congenital heart disease (CHD).
For the study, recently published in European Radiology, researchers compared radiation exposure levels and image quality in 37 patients who had cardiac PCCT (mean age of 794 days) to 37 patients who had cardiac EID CT (mean age of 815 days).
The researchers found no significant difference between PCCT and EID CT in regard to signal-to-noise ratio (SNR) (6.63 vs. 6.41), contrast-to-noise ratio (CNR) (18.67 vs. 19.38) and beam-hardening artifacts (13.16 vs. 12.45). Incorporating a 5-point Likert scale, reviewing radiologists rated the overall image quality of cardiac PCCT and cardiac EID CT the same at a mean of 3.73.
However, the study authors pointed out a significant reduction of radiation dosing exposure with the use of cardiac PCCT. PCCT had a 45 percent lower mean volume CT dose index (CTDlvol) (0.20 mGy) in comparison to EID CT (0.37 mGy), and a 43.7 percent lower mean dose length product (DLP) (4.06 mGy*cm vs. 7.21 mGy*cm).
“In our study, despite the significantly reduced radiation dose of PCD CT examinations, qualitative assessment of proximal coronary arteries remained comparable to studies from the EID CT system,” noted lead study author Susanne Hellms, M.D., who is affiliated with the Institute of Diagnostic and Interventional Radiology at Hannover Medical School in Hannover, Germany.
Three Key Takeaways
- Comparable image quality. Cardiac photon-counting CT (PCCT) provides similar image quality to energy-integrating detector CT (EID CT) in pediatric patients with congenital heart disease (CHD), with no significant differences in signal-to-noise ratio, contrast-to-noise ratio, or artifact levels.
- Significantly lower radiation dose. PCCT offers a notable reduction in radiation exposure with 45 percent lower mean CT dose index and 43.7 percent lower dose length product compared to EID CT, critical benefits for younger, more radiosensitive patients.
- Potential for enhanced imaging. PCCT may offer additional imaging advantages such as better spatial and contrast resolution, reduced electronic noise and artifacts, and improved iodine signal, potentially making it a more effective tool for assessing complex pediatric cardiac anatomy.
Emphasizing the challenges of imaging often intricate congenital anatomy and the increased vulnerability of younger pediatric patients to radiation exposure, the study authors emphasized other advantages with the use of PCCT.
“Compared to energy-integrator detector CT (EID CT), PCD CT has been described to offer improved spatial and contrast resolution, less electronic noise, less blooming, metal and beam-hardening artifacts, and increased iodine signal after contrast medium application. Due to the possible benefits, PCD CT has the potential to address the challenges of cardiac CT, including the need for a high spatial and contrast resolution,” added Hellms and colleagues.
(Editor’s note: For related content, see “Study Shows Enhanced Diagnosis of Coronary Artery Stenosis with Photon-Counting CTA,” “Photon-Counting Computed Tomography: Eleven Takeaways from a New Literature Review” and “Can Emerging AI Software Offer Detection of CAD on CCTA on Par with Radiologists?”)
In regard to study limitations, the authors acknowledged the small cohort size and conceded that electrocardiographic gating, which was not utilized in this study, may have enhanced image quality. They also noted that patients with metallic devices were excluded from the study.
