MR imaging characteristics of soft tissue vascular anomalies in children.

Accurate classification of soft tissue vascular anomalies is critical since treatment options and morbidity differ significantly for the various groups of vascular anomalies (VA). A classification system introduced by Mulliken and Glowacki in 1982 explained the biology of VA, thus resulting in improved management and communication between different disciplines taking care of children with soft tissue vascular anomalies. This classification has been updated by the International Society for the Study of Vascular Anomalies in 1996 and forms the basis for the current nomenclature. Although the majority of vascular anomalies can be accurately classified by their clinical history and a physical exam, imaging is necessary to determine the full anatomical extent of the anomaly, to follow up treatment response, to confirm diagnosis, and to provide correct classification in challenging cases when necessary. This article will review the key magnetic resonance imaging (MRI) features of most common soft tissue vascular anomalies in children. MRI and dynamic contrast-enhanced magnetic resonance angiography are crucial for the evaluation of vascular anomalies in children because of lack of radiation, high soft tissue resolution, and the capability of dynamic contrast-enhanced images to reflect the hemodynamics of the anomalies.