MRI Characteristics of Spinal Ependymoma in WHO Grade II: A Review of 59 Cases

Spine (Phila Pa 1976). 2018 May 1;43(9):E525-E530. doi: 10.1097/BRS.0000000000002496.


Study design: Retrospective multicenter study.

Objective: The goal of this study is to determine the characteristic imaging features of spinal ependymoma in a review of magnetic resonance imaging (MRI) data for a large series of surgically proven cases.

Summary of background data: Common spinal intramedullary neoplasms are mostly ependymomas and comprise 50% to 60% of spinal neuroepithelial tumors in adults. Preoperative prediction of the pathological diagnosis could enhance surgical planning and explanation of the procedure to patients. However, these types of tumors exhibit a variety of MRI findings.

Methods: Records were examined for 59 patients who underwent surgery for spinal cord ependymoma and had a pathological diagnosis of cellular ependymoma of World Health Organization classification grade II.

Results: The ependymomas included 28 in the cervical spine, 34 in the thoracic spine, and 3 conus lesions. All cases were isointense or hypointense on T1-weighted MRI, and 55 (93%) were hyperintense on T2-weighted MRI. Tumors were located centrally in all cases; 50 (85%) showed surrounding cord edema; and 52 (88%) had associated cysts, including 36 (61%) rostral or caudal cysts, 10 (17%) intratumoral cysts, and 6 (10%) with syringomyelia. Of the 59 tumors, 17 (29%) showed the "cap sign," a rim of extreme hypointensity seen around the tumor on T2-weighted images, due to hemosiderin. In gadolinium-enhanced MRI, all cases were enhanced, and 27 (46%), 16 (27%), 11 (19%), and 5 (8%) cases showed homogeneous, heterogeneous, rim, and nodular enhancement, respectively.

Conclusion: Hypointense changes on T2-weighted MRI and hemosiderin deposition reflect easy bleeding. Tumors are associated with various types of cysts, and gadolinium-enhancement patterns reflect a variety of intratumor cellular components. In cases in which the whole tumor shows gadolinium enhancement on MRI, rostral, or caudal cyst and a cap sign with hemorrhage are characteristics of grade II classical ependymoma.

Level of evidence: 3.

Publication types

  • Case Reports
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Cervical Vertebrae
  • Ependymoma / diagnostic imaging*
  • Ependymoma / surgery*
  • Female
  • Humans
  • Magnetic Resonance Imaging / methods
  • Magnetic Resonance Imaging / standards*
  • Male
  • Middle Aged
  • Neoplasm Grading / methods
  • Neoplasm Grading / standards
  • Retrospective Studies
  • Spinal Neoplasms / diagnostic imaging*
  • Spinal Neoplasms / surgery*
  • Thoracic Vertebrae
  • World Health Organization*
  • Young Adult