In many cases, US can help differentiate between the various types of vascular malformations and other soft-tissue lesions [5,7,13-15]. However, US has limitations in regard to field of view and tissue penetration that typically limits the ability to completely characterize and delineate the full extent of vascular malformations. Additional cross-sectional imaging, such as MRI, is usually needed for complete characterization [2,8,9]. US Extremity Area of Interest with IV Contrast Limited evidence is available regarding the utility of CEUS specifically for the evaluation of peripheral vascular malformations, but this may be considered in select cases. Visualization of small arteriovenous shunts may be improved with CEUS compared with US with Doppler [16]. The potential for quantifying perfusion in vascular malformations with CEUS could also be useful in assessing treatment response [17]. CTA Extremity CTA features comparatively high spatial resolution, which allows for the characterization of a vascular nidus, enlarged feeding arteries, and draining veins that are frequently encountered in high-flow lesions that often present clinically with a vascular murmur [10]. CTA may also be useful for the assessment of other vascular- related pathologies, such as vasculitis and compression syndromes [10]. However, poor soft-tissue contrast and limited temporal resolution are drawbacks to this modality, and MRA is typically preferred over CTA [10,18]. MRI Extremity The high tissue contrast of MRI makes it a preferred modality to assess the extent and distribution of vascular malformations, which are often underestimated by physical examination alone [2,5]. MRI is also a good option to evaluate for other soft-tissue lesions that may be included within a differential diagnosis of bruit on clinical examination [19,23]. The use of IV contrast improves lesion characterization and optimizes visualization of the surrounding anatomy [3,6,20].
Clinically Suspected Vascular Malformation of the Extremities. In many cases, US can help differentiate between the various types of vascular malformations and other soft-tissue lesions [5,7,13-15]. However, US has limitations in regard to field of view and tissue penetration that typically limits the ability to completely characterize and delineate the full extent of vascular malformations. Additional cross-sectional imaging, such as MRI, is usually needed for complete characterization [2,8,9]. US Extremity Area of Interest with IV Contrast Limited evidence is available regarding the utility of CEUS specifically for the evaluation of peripheral vascular malformations, but this may be considered in select cases. Visualization of small arteriovenous shunts may be improved with CEUS compared with US with Doppler [16]. The potential for quantifying perfusion in vascular malformations with CEUS could also be useful in assessing treatment response [17]. CTA Extremity CTA features comparatively high spatial resolution, which allows for the characterization of a vascular nidus, enlarged feeding arteries, and draining veins that are frequently encountered in high-flow lesions that often present clinically with a vascular murmur [10]. CTA may also be useful for the assessment of other vascular- related pathologies, such as vasculitis and compression syndromes [10]. However, poor soft-tissue contrast and limited temporal resolution are drawbacks to this modality, and MRA is typically preferred over CTA [10,18]. MRI Extremity The high tissue contrast of MRI makes it a preferred modality to assess the extent and distribution of vascular malformations, which are often underestimated by physical examination alone [2,5]. MRI is also a good option to evaluate for other soft-tissue lesions that may be included within a differential diagnosis of bruit on clinical examination [19,23]. The use of IV contrast improves lesion characterization and optimizes visualization of the surrounding anatomy [3,6,20].