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Cardiovascular CT angiography in neonates and children: image quality and potential for radiation dose reduction with
Francesco Tricarico1, Anthony M Hlavacek, U Joseph Schoepf
1Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, 25 Courtenay Drive, MSC 226, Charleston, SC 29401, USA.
Insights
Iterative reconstruction techniques significantly enhance image quality in low-radiation-dose paediatric cardiovascular CT angiography (CTA), allowing for further radiation dose reductions without compromising diagnostic image quality.
Area of Science:
- Radiology
- Medical Imaging
- Pediatric Cardiology
Background:
- Low-radiation-dose computed tomography angiography (CTA) is crucial for pediatric cardiovascular imaging.
- Optimizing image quality (IQ) while minimizing radiation exposure remains a challenge.
Purpose of the Study:
- To evaluate the image quality of low-radiation-dose pediatric cardiovascular CTA.
- To compare iterative reconstruction techniques (IRIS, SAFIRE) against filtered back-projection (FBP).
- To assess the potential for further radiation dose reduction.
Main Methods:
- Forty neonates and children underwent low-radiation-dose CTA.
- Data were reconstructed using FBP, IRIS, and SAFIRE.
- Half-dose acquisitions were simulated for ECG-synchronized studies.
- Image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and subjective IQ were assessed.
Main Results:
- Iterative reconstruction (IRIS, SAFIRE) significantly reduced image noise and increased SNR/CNR compared to FBP (P < 0.001).
- Half-dose SAFIRE demonstrated superior image quality compared to both full- and half-dose FBP (P < 0.001).
- Subjective IQ scores were higher with IRIS and SAFIRE, especially in half-dose SAFIRE studies.
Conclusions:
- Iterative reconstruction techniques substantially improve image quality in low-radiation-dose pediatric cardiovascular CTA.
- These techniques enable further radiation dose reduction without compromising diagnostic image quality.
- Iterative reconstruction offers a promising approach for safer, high-quality pediatric cardiovascular imaging.
Objectives:
To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions.
Methods:
Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated.
Results:
Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv.
Conclusions:
IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ.
Key Points:
• Iterative reconstruction techniques significantly improve non-invasive cardiovascular CT in children. • Using half traditional radiation dose image quality is higher with iterative reconstruction. • Iterative reconstruction techniques may allow further radiation reductions in paediatric cardiovascular CT.
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