J Korean Soc Magn Reson Med.
1997 Dec;1(1):119-124.
Perfusion MR Imaging of the Brain Tumor: Preliminary Report
Abstract
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PURPOSE: To assess the utility of magnetic resonance(MR) cerebral blood volume (CBV) map in the evaluation of brain tumors.
MATERIALS AND METHODS
We performed perfusion MR imaging preoperatively in the consecutive 15 patients with intracranial masses (3 meningiomas, 2 glioblastoma multiformes, 3 low grade gliomas, 1 lymphoma, 1 germinoma, 1 neurcyotma, 1 metastasis, 2 abscesses, 1 radionecrosis ). The averages age of the patients was 42 years (22yr-68yr), composed of 10 males and 5 females. All MR images were obtained at 1.5T imager(Signa, GE Medical systems, Milwaukee, Wisconsin). The regional CBV map was obtained on the theoretical basis of susceptibility difference induced by first pass circulation of contrast media.(contrast media: 15cc of gadopentate dimeglumine, about 2ml/sec by hand, staring at 10 second after first baseline scan). For each patient, a total of 480 images (6 slices, 80 images/slice in 160 sec) were obtained by using gradient echo(GE) single shot echo-planar image(EPI) sequence (TR 2000ms, TE 50ms, flip angle 90degree, FOV 240x240, matrix 128x128, slice-thick/gap 5/2.5). After data collection, the raw data were transferred to GE workstation and rCBV maps were generated from the numerical integration of deltaR2* on a voxel by voxel basis, with home made software(deltaR2*=-ln(S/S0/TE). For easy visual interpretation, relative RGB color coding with reference to the normal white matter was applied and color rCBV maps were obtained. The findings of perfusion MR image were retrospectively correlated with Gd-enhanced images with focus on the degree and extent of perfusin and contrast enhancement.
RESULTS
Two cases of glioblastoma multiforme with rim enhancement on Gd-enhanced T1 weighed image showed increased perfusion in the peripheral rim and decreased perfusion in the central necrosis portion. The low grade gliomas appeared as a low perfusion area with poorly defined margin, In 2 cases of brain abscess, the degree of perfusion was similar to that of the normal white matter in the peripheral enhancing rim and was low in the central portion. All meningiomas showed diffuse homogeneous increased perfusion moderate or high degree. One each of lymphoma and germinoma showed homogenously decreased perfusion with well defined margin. The central neurocytoma showed multifocal increased perfusion areas of moderate or high degree. A few nodules of the multiple metastasis showed increased perfusion of moderate degree. One radionecrosis revealed multiple foci of increased perfusion within the area of decreased perfusion.
CONCLUSION
The rCBV map appears to correlate well with the perfusion state of brain tumor, and may be helpful in discrimination between low grade and high grade glioma. The further study is needed to clarify the role of perfusion MR image in the evaluation of brain tumor.