Preoperative evaluation of intraabdominal tumors in children: gradient-recalled echo vs spin-echo MR imaging.
OBJECTIVE
The purpose of this study was to compare gradient-recalled echo (GRE) with spin-echo (SE) MR imaging in the assessment of vessel patency and tumor margins in children with intraabdominal tumors.


METHODS
Findings on GRE and SE images in 10 children with abdominal neoplasms were retrospectively evaluated and compared with pathologic findings or results of CT studies.


RESULTS
Detection of tumor thrombus was 100% with GRE sequences and 75% with SE sequences. The SE sequences yielded two false-positive diagnoses of tumor thrombosis, whereas the GRE sequences yielded no false-positive or false-negative diagnoses. In patients with extrinsic compression of the inferior vena cava by tumor, GRE images were consistently better than SE images for confirming vessel patency. GRE images also were superior to SE images at showing flow in mesenteric vessels, renal arteries, and renal veins. However, GRE images displayed tumor margins less well than SE images did, and they were also more susceptible to ghosting artifacts.


CONCLUSIONS
Our results suggest that the GRE sequence is a useful adjunct to SE sequences for evaluating vascular involvement in children with abdominal tumors.
Mallinckrodt Institute of Radiology, Washington University School of Medicine, Department of Radiology, St. Louis, MO 63110.
K L
KL
Shady
M J
MJ
Siegel
J J
JJ
Brown
D000008:Abdominal Neoplasms / Q000175:diagnosis* / Q000601:surgery; D000293:Adolescent; D016477:Artifacts; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008641:Mesenteric Vascular Occlusion / Q000175:diagnosis; D009360:Neoplastic Cells, Circulating; D011169:Portal Vein / Q000473:pathology; D012077:Renal Artery / Q000473:pathology; D012082:Renal Veins / Q000473:pathology; D012189:Retrospective Studies; D014654:Vascular Patency; D014682:Vena Cava, Inferior / Q000473:pathology