Phleboliths may also be seen and provide a clue to the diagnosis of venous malformations and hemangiomas, which are reported to contain phleboliths in 20% to 67% of cases [3,12]. Lesions located adjacent to bone may be associated with bone changes, including periosteal reaction, remodeling, or signs of destruction, such as cortical scalloping and lucencies. Although such findings may be visible radiographically, they are not specific for the diagnosis of vascular malformations [6,12]. US Duplex Doppler Extremity Ultrasound (US) with duplex Doppler imaging can be useful for the initial assessment of suspected vascular malformation, particularly if a focal mass or other targetable superficial symptomatology is present. US with Doppler can differentiate high-flow from low-flow malformations, and often provides a specific diagnosis in cases where characteristic vascular malformation features are present [3,5,13,14]. US may also be diagnostic of other lesions within the differential diagnosis for nonspecific extremity complaints [3,15]. Ultimately, this modality is limited in regards to tissue penetration and a small imaging field of view, which may lead to suboptimal evaluation of lesion extent and size, particularly if located deep in the extremity or adjacent to bone [2,8,13]. As a result, cross-sectional imaging, such as MRI, may be needed for more complete evaluation and definitive diagnosis [1,3,13], especially in cases without a targetable focal abnormality. US Extremity Area of Interest with IV Contrast There is limited evidence regarding the utility of contrast-enhanced US (CEUS) in evaluating suspected peripheral vascular malformations, but this modality may be considered in select cases. The addition of microbubble contrast may enhance visualization of small arteriovenous shunts and low-flow vessels compared with US with Doppler [16].
Clinically Suspected Vascular Malformation of the Extremities. Phleboliths may also be seen and provide a clue to the diagnosis of venous malformations and hemangiomas, which are reported to contain phleboliths in 20% to 67% of cases [3,12]. Lesions located adjacent to bone may be associated with bone changes, including periosteal reaction, remodeling, or signs of destruction, such as cortical scalloping and lucencies. Although such findings may be visible radiographically, they are not specific for the diagnosis of vascular malformations [6,12]. US Duplex Doppler Extremity Ultrasound (US) with duplex Doppler imaging can be useful for the initial assessment of suspected vascular malformation, particularly if a focal mass or other targetable superficial symptomatology is present. US with Doppler can differentiate high-flow from low-flow malformations, and often provides a specific diagnosis in cases where characteristic vascular malformation features are present [3,5,13,14]. US may also be diagnostic of other lesions within the differential diagnosis for nonspecific extremity complaints [3,15]. Ultimately, this modality is limited in regards to tissue penetration and a small imaging field of view, which may lead to suboptimal evaluation of lesion extent and size, particularly if located deep in the extremity or adjacent to bone [2,8,13]. As a result, cross-sectional imaging, such as MRI, may be needed for more complete evaluation and definitive diagnosis [1,3,13], especially in cases without a targetable focal abnormality. US Extremity Area of Interest with IV Contrast There is limited evidence regarding the utility of contrast-enhanced US (CEUS) in evaluating suspected peripheral vascular malformations, but this modality may be considered in select cases. The addition of microbubble contrast may enhance visualization of small arteriovenous shunts and low-flow vessels compared with US with Doppler [16].