Stratification of Grade of Spinal Cord Non-Ependymal Gliomas by Magnetic Resonance Imaging

Abstract

The purpose of this study was to demonstrate the usefulness of conventional magnetic resonance imaging (MRI) in stratification of spinal cord non-ependymal gliomas. Forty-one patients (mean age, 29.9 ± 16.8 years; 27 men) with first-diagnosed spinal cord non-ependymal gliomas underwent conventional MRI including T1-weighted, T2-weighted (T2W) and contrast-enhanced T1-weighted imaging sequences. The tumors were removed by surgery and processed by histology 1 week after MRI. Patients were divided into low-grade and high-grade groups according to histological findings. The MRI features of gliomas including signal-to-noise-ratio (SNR), margins, heterogeneity, edema, enhancement, tumor size, longitudinal location, and presence of syrinx were measured and compared between low-grade and high-grade groups using the χ2 test and the Mann-Whitney U test. The SNR of low-grade gliomas on T2W images was significantly higher than that of high-grade gliomas (165.0 ± 108.7 vs. 98.6 ± 44.4; P= 0.016 by the Mann-Whitney U test). The margins of low-grade gliomas were found to be clearer compared to that of high-grade gliomas (54.5% vs. 5.3%; P=0.001). Receiver-operating-characteristic analysis revealed that the area under the curve of 1/SNR, margin and the combination of 1/SNR and margin was 0.722 (95% confidence interval [CI], 0.564-0.880), 0.736 (95% CI, 0.578-0.894), and 0.845 (95% CI, 0.717-0.973), respectively. No significant differences were found in the heterogeneity, edema, enhancement level,enhancement SNR, size, longitudinal location, cyst, hemorrhage, and intramedullary location between low-grade and high-grade non-ependymal gliomas (all P > 0.05). The characteristics of signal intensity and margin on T2W imaging are valuable in stratification of spinal cord non-ependymal gliomas.