Body MR angiography in children: how we do it

Abstract

Vascular pathology is ubiquitous in children. Common indications for angiographic imaging in the body include congenital anomalies, portal hypertension, assessing resectability of neoplasms, renovascular hypertension, vascular malformations, vasculitis, systemic vein thrombosis, and trauma. MR angiography, with or without the use of intravenous contrast agents, is therefore a mainstay in the repertoire of MR imaging in children. Pediatric contrast-enhanced MR angiography has benefited from several innovations in recent years, including improved hardware options like high-field-strength scanners and integrated high-density coil arrays, new sequences that combine parallel imaging, innovative k-space sampling and Dixon fat suppression with time-resolved imaging, new contrast agents with longer blood-pool residence time, and advanced post-processing solutions like image fusion. This article focuses on the principles of contrast-enhanced MR angiography of the body as it pertains to the physiologies and pathologies encountered in children. It also discusses tools to adapt the MR angiographic technique to the clinical indication, as well as pitfalls of post-processing and interpretation in commonly encountered vascular imaging scenarios in the pediatric body.

Clinical value of classification of venous malformations with contrast-enhanced MR Angiography

“…Application of high 3 tesla scanner using higher strength of the gradient systems provides a higher signal from the blood and suppression of the background that can be used to obtain images with higher spatial resolution. 22 The use of parallel imaging improves the image quality and spatial resolution by increasing the anatomic coverage and removing the aliasing artifact. 9,10 Applications of four-dimensional MRA accelerate the dynamic MRA scans up to 60 times with a sub-second temporal sampling rate and follow contrast hemodynamics with the near-isotropic spatial resolution of 1–1.5 mm that helps for better delineation of venous drainage.…”

“…The CE-MRA adds information about the presence or absence of deep and superficial conducting veins and their morphology, as well as the presence or absence of primitive venous channels. [22][23][24][25][26] To our knowledge, there is no previous study that discusses the role of CE-MRA in assessment of venous malformations.…”