Preoperative fast MRI of brain tumors using three-dimensional segmented echo planar imaging compared to three-dimensional gradient echo technique

The purpose of this study was to compare the diagnostic efficacy of a newly developed T-1-weighted three-dimensional segmented echo planar imaging (3D EPI) sequence versus a conventional T-1-weighted three dimensional spoiled gradient echo (3D GRE) sequence in the evaluation of brain tumors. Forty-f our patients with cerebral tumors and infections were examined on a 1.0 T M R unit with 23 mT/m gradient strength. The total scan time for the T, 3D EP I sequence was 2 min 12 s, and for a conventional 3D GRE sequence it was 4 min 59 s. Both sequences were performed after administration of a contrast agent. The images were analyzed by three radiologists. Image assessment cri teria included lesion conspicuity, contrast between different types of norm al tissue, and image artifacts. In addition, signal-to-noise and contrast-t o-noise-ratio (C/N) were calculated. The gray-white differentiation and C/N ratio of 3D EPI were found to be inferior to conventional 3D GRE images, b ut the difference was not statistically significant. In the qualitative com parison, lesion detection and conspicuity of 3D EPI images and conventional 3D GRE images were similar, but a tow-fold reduction of the scanning time was obtained. With the 3D EPI technique, a 50% scan time reduction could be achieved with acceptable image quality compared to conventional 3D GRE. Th us, the 3D EPI technique could replace conventional 3D GRE in the preoperat ive imaging of brain. (C) 2000 Elsevier Science Inc. All rights reserved.