Various MRI Findings of Spinal Ependymoma

Purpose To present the typical and atypical magnetic resonance image (MRI) findings of intramedullary spinal ependymomas, and compare these findings with pathological subtypes. Materials and Methods Between January 2003 to November 2014, 47 patients who had spinal ependymoma with pathologic confirmation, were retrospectively reviewed with all electronic medical records and MR images. MR imaging was done in all cases, and the images of spinal ependymomas and associated enhancement patterns were correlated with pathologic findings. Results The enhancement patterns were categorized into four categories: homogeneous, heterogeneous, rim-enhancement, and non-enhancement. Heterogeneous enhancement was observed in 50% of the cases. Among the 47 cases, 35 cases were well-marginated, with 21 being cervically located. All lesions were centrally located in the axial axis. Most of the cases showed T1-iso signal intensity (81%) and T2-high signal intensity (72%). The hemosiderin cap sign, syringomyelia, tumoral and non-tumoral cysts were well demonstrated. The most common pathologic type was cellular ependymoma. However, due to the small sample size, we believe it inappropriate to statistically discuss the MRI findings according to the pathologic subtype. Conclusion Most spinal ependymoma showed T1-iso signal intensity and T2-high signal intensity, with enhancement patterns other than homogeneous enhancement.