Radiation Exposure of Thoracic Computed Tomography Angiographies in Neonates and Children with Congenital and Acquired Cardiovascular Diseases

Objectives: This study was aimed to retrospectively analyze radiation exposure of thoracic computed tomography angiographies (CTA) in pediatric patients with congenital and acquired cardiovascular disease using a third-generation dual source scanner (Siemens, Force).

Methods: In 111 patients (age: mean& &±& SD: 4.3 &±& 5.1 years; range: 0–16 years) a total number of 141 CTA examinations of the thorax with ECG synchronization were performed after intravenous contrast application (Imeron 400, Bracco Imaging S.p.A; 1 mL/kg body weight). We retrospectively evaluated dose length product (DLP) and calculated effective doses (E) thereof using age and kV specific conversion factors.

Result: Mean &±& SD dose length products were DLP (all) = 22.5 &±& 26.0 mGycm. When analyzing age-specific subgroups, mean values were DLP (neonates) = 4.8& &±& 2.2 mGycm, DLP (infants) = 7.0 &±& 3.4 mGycm, and DLP (children > 1 year) = 34.1 &±& 29.2 mGycm, respectively. Corresponding mean effective dose for all examinations was E (all) = 0.81 &±& 0.73 mSv. When analyzing age-specific subgroups, mean effective doses were E (neonates) = 0.34& &±& 0.19 mSv, E (infants) = 0.53 &±& 0.27 mSv, and E (children > 1 year) = 0.96 &±& 0.67 mSv. There were no complications associated with the contrast agent application, such as allergic reactions or contrast agent extravasation. Diagnoses included anomalies of the ventriculoarterial junction and outflow tracts, of the pulmonary veins, as well as aortic arch and coronary anomalies. Acquired cardiac diseases included, that is, dissection of left coronary artery and follow-up examinations after cardiac surgery.

Conclusion: Thoracic CTA in neonates and children can be acquired routinely with a radiation exposure below 1 mSv for a broad spectrum of cardiovascular diseases. This modality represents a safe and fast noninvasive imaging approach in the workup of congenital and acquired cardiovascular diseases.