MR LYMPHANGIOGRAPHY IN INFANTS, CHILDREN, AND YOUNG-ADULTS

OBJECTIVE, Our objective was to offer a preliminary description of MR lymphangiography; its uses and limitations; and its findings in infant s, children, and young adults. SUBJECTS AND METHODS. Twenty-nine patie nts underwent 32 MR lymphangiographic examinations for evaluation of v ascular malformations, other masses, soft-tissue swelling, gigantism, fluid accumulation, or pain. MR lymphangiography was based on a heavil y T2-weighted fast spin-echo sequence and a maximum-intensity-projecti on algorithm. We assessed the axial and off-axial lymphatic channels i n conjunction with MR venography to help differentiate veins from lymp hatics. Correlation was made with published lymphangiograms and anatom ic diagrams to assist interpretation and (when available) with histolo gic specimens (n = 11)for validation. RESULTS. Presumed lymphatic chan nels were seen universally, although 14 examinations showed incomplete venous signal suppression. Lymphatic channels appeared normal in eigh t children and in 20 of the 21 asymptomatic contralateral limbs. Ten p atients had an increased number and size of off-axial channels, includ ing seven children with large, diffuse low-flow vascular malformations . Enlarged axial and off-axial channels were seen in five patients, fo ur of whom had Klippel-Trenaunay syndrome. Six patients, each with an extensive hemangioendothelioma, Klippel-Trenaunay syndrome, Gorham syn drome, or unilateral body edema, showed absence or interruption of axi al channels. CONCLUSION. MR lymphangiography appears to be a useful no ninvasive technique to study superficial and deep lymphatic channels i n children with local or diffuse vascular lesions or swelling of extre mities. Its limitations notwithstanding, the technique may offer furth er insight into the nature of vascular anomalies, may direct therapy, and may predict prognosis.