First-Pass and Steady-State MR Angiography of Thoracic Vasculature in Children and Adolescents

Magnetic resonance angiography (MRA) is an established noninvasive imaging modality for detection and evaluation of vascular pathologies in children with congenital heart disease. Standard first-pass (FP)–MRA uses a 3-dimensional MRA sequence with an extracellular contrast agent, in which spatial resolution is limited by breath-hold duration, and image quality (IQ) is limited by motion artifacts. The purpose of this study was to compare the diagnostic confidence, IQ, and image artifacts of standard FP-MRA to a high-resolution, motion compensated steady-state (SS)–MRA of the thoracic vasculature in children and adolescents with congenital heart disease using a blood-pool contrast agent (gadofosveset trisodium). SS-MRA of the thoracic vasculature (technically successful in 90% of patients) offers superior diagnostic confidence and IQ compared with FP-MRA and shows fewer motion-related image artifacts. In addition, SS-MRA revealed findings missed by FP-MRA. Therefore, SS-MRA may prove specifically beneficial for imaging of thoracic vessels that are small and/or subject to motion.