MR Imaging Features and Differential Diagnosis of Spinal Cord Ependymomas

Objective To study the MR imaging features of spinal cord ependymomas.Materials and Methods 16 cases of ependymomas with histologically confirmed were retrospectively reviewed in terms of location, size, pattern of growth,signal intensity, enhancement pattern as well as the presence or absence of cyst, hemorrhage and “cap sign” on MR imaging.Results All spinal cord ependymomas were showed as epicenteral growth and 3 cases of filar ependymomas combined with intervertebral foramina dilatation. The average number of vertebral segments involved with tumors was 2.7. Most of tumors were iso or hypointense on T_1WI and all of tumors were hyperintense on T_2WI. 10 cases of spinal ependymomas were associated with rostral and/or caudal reactive cysts. A cystic component was seen in 3 spinal ependymomas. Intratumoral hemorrhage occurred in 2 cases of spinal ependymomas. “Cap sign” was seen in 5 cases of tumors on T_2WI imaging. 15 cases of tumors were obviously enhanced and 14 cases had well-defined margins.Conclusion Spinal cord ependymomas have certain MR features, which are very helpful to make correct preoperative diagnosis and differential diagnosis.