Dynamic MRI for Distinguishing High-Flow from Low-Flow Peripheral Vascular Malformations

OBJECTIVE. The purpose of our study was to assess the usefulness of dynamic MRI in distinguishing high-flow vascular malformations from low-flow vascular malformations, which do not need angiography for treatment.SUBJECTS AND METHODS. Between September 2001 and January 2003, 16 patients who underwent conventional and dynamic MRI had peripheral vascular malformations (six high- and 10 low-flow). The temporal resolution of dynamic MRI was 5 sec. Time intervals between beginning of enhancement of an arterial branch in the vicinity of a lesion in the same slice and the onset of enhancement in the lesion were calculated. We defined these time intervals as “artery–lesion enhancement time.” Time intervals between the onset of enhancement in the lesion and the time of the maximal percentage of enhancement above baseline of the lesion within 120 sec were measured. We defined these time intervals as “contrast rise time” of the lesion. Diagnosis of the peripheral vascular malformations was based on angiographic or v...