Susceptibility-weighted imaging in grading brain astrocytomas

Objective: To evaluate the value of intratumoral vessels and micro-hemorrhage shown in susceptibility weighted imaging (SWI) for grading brain astrocytomas and to analyze the difference between SWI and conventional imaging techniques. Methods: 22 patients with astrocytomas were diagnosed with surgical specimens, 9 of which were grades I-II, and 13 were grades III-IV. All examinations were performed on Signa DEx 3.0 T MRI scanner. Conventional imaging techniques ( T1WI, T2WI, T2FLAIR, CE-T1WI) and SWI sequence were used. The parameters of SWI sequence were the following: TR = 35 ms, TE = 20 ms, FA = 15 degrees, slice thickness = 2mm. The small vessels and blood products of the tumors in SW images were analyzed. The differences between the two groups in SW images were analyzed statistically. Results: The findings in SW images of brain astrocytomas were correlated strongly with pathology. SWI was more sensitive compared to conventional imaging techniques for showing small vessels and micro-hemorrhage in brain astrocytomas. Statistical comparison showed that the small vessels and micro-hemorrhage of two groups of brain astrocytomas in SW images differed significantly. Conclusion: SWI is superior to conventional imaging techniques at showing the small vessels and micro-hemorrhage in brain astrocytomas, which plays an important role in the tumor grading. (C) 2009 Elsevier Ireland Ltd. All rights reserved.