CONTRAST-ENHANCED T1-WEIGHTED 3-DIMENSIONAL GRADIENT-ECHO MR-IMAGING OF THE WHOLE SPINE FOR INTRADURAL TUMOR DISSEMINATION

BACKGROUND AND PURPOSE: When evaluating intradural tumor dissemination in the spine, contrast-enhanced T1-weighted 2D spin-echo (2D-SE) imag es are frequently problematic because most of the lesions are very sma ll. Our purpose was to compare 2D-SE images with 3D gradient-echo (3D- GE) postcontrast images to determine which technique is better for dep icting intradural tumor dissemination. METHODS: Ten patients with and 10 without intradural tumor dissemination were examined prospectively with MR imaging. After contrast administration, all patients underwent sagittal imaging with 2D-SE and 3D-GE sequences. Subsequently, the 2D -SE, 3D-GE, and multiplanar reconstruction (MPR) images of the 3D-GE s equence were evaluated for image quality, lesion detectability, signal -to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the dissem inated lesions. RESULTS: Although delineation of spinal cord from CSF was slightly poorer on the 3D-GE sequences than on the 2D-SE sequences , the difference was not significant. In the evaluation of image artif acts and contrast between spinal cord and CSF, there was no significan t difference. In seven patients with nodular enhancement, the 3D-GE se quence detected 46 lesions and the 2D-SE sequence detected 36, With MP R, the greatest number of lesions (n = 51) was detected, and vascular enhancement was clearly distinguished. There was no difference in SNR and CNR of lesions between the 3D-GE and 2D-SE sequences. CONCLUSION: The contrast-enhanced 3D-GE technique offers advantages over 2D-SE ima ging in detecting intradural tumor dissemination, especially when the MPR technique is applied. This technique should be used for detecting intradural tumor dissemination.