Purpose or Case Report: Computed Tomography Angiography (CTA) is a valuable non-invasive tool for assessment of congenital heart disease in neonates. Though it requires less radiation, contrast and sedation than catheter angiography, which is the current standard of care, traditional CTA can still necessitate significant radiation dose, sedation, breath-holding and/or low heart-rates to achieve diagnostic studies. In this frequently imaged neonatal patient population, it is imperative to minimize cumulative radiation to limit the lifetime risk of cancer. At our institution, we have successfully used a new fast-acquisition FLASH CTA protocol to achieve high quality imaging of neonates with complex congenital heart disease with minimal radiation dose and without sedation.
Methods & Materials: Nineteen neonatal patients with complex congenital heart disease who required pre-surgical imaging underwent FLASH CTA from 8/2010-9/2015. Two of these patients had repeat examinations, for a total of 21 studies. At time of examination, the patients ranged in age from 1-30 days (median 7 days) and weighed 1.3-4.1 kg (median 3.7 kg) at the time of imaging. In all cases, imaging was performed on a dual source Siemens CT machine, the Somatom Definition Flash, using the FLASH protocol. Images were acquired from the thoracic inlet to top of the abdomen. Images interpretation was performed by experienced radiologists and cardiologists. All examinations were performed awake with free breathing and without sedation.
Results: All 21 examinations were considered diagnostic quality by the interpreting physician. Radiation dose ranged from 0.2-3.4 mGy (CTDi) and 3-33 mGy-cm (DLP). In fact, as the protocol was refined over time, radiation dose decreased: for the 14 examinations done in 2014-2015, the radiation dose ranged from 0.2-0.7 mGy (CTDI) and 3.0-14.0 mGy-cm (DLP). No adverse events or complications were associated with the examinations.
Conclusions: Our experience suggests that FLASH CTA offers diagnostic image quality with low radiation dose and no need for sedation in neonates with congenital heart disease.