Comparing Features of Different Location of Ependymomas on MR Imaging

Objective: To compare the age distribution and characteristic MR imaging findings of ependymomas for each typical location. Materials and Methods: 58 cases of ependymomas with histologically confirmed were retrospectively reviewed in terms of age distribution,location,size,pattern of growth,signal intensity,the presence or absence of cyst and hemorrhage as well as enhancement pattern on MR imaging. Results: Among the 58 patients,supratentorial ependymomas were 27(46.6%) cases,and the age distribution of most cases was between the third and fifth decade,20 cases of supratentorial ependymomas lie in lateral cerebral ventricle.Infrartentorial tumors were 20(34.5%)cases,and the age distribution of cases was before the second decade,almost of infrartentorial tumors lie in the fourth ventricle.Spinal cord ependymomas were 11(18.9%).The signal intensity of the ependymomas was non-specific,regardless of their location.A cystic component was seen in 70.4% of supratentorial,55% of infratentorial,and 18.2% of spinal cord ependymomas.The spinal cord ependymomas which were associated with reactive cysts were 45.5%.Intratumoral hemorrhage occurred in 29.6% of supratentorial,20% of infratentorial,and 9% of spinal cord tumors.Eighty percent of lateral cerebral ventricle ependymomas extended to opposite side ventricle,In fourth ventricle,16 cases of tumors extended caudally via Magendie foramen,and 12 cases into the cerebellopontine angel through the foramen of Luschka.All spinal cord ependymomas showed epicentral growth,and intervertebral foramina enlarged was displayed in one case of filar ependymomas. Conclusion: Ependymomas for each typical location have differential in age distribution,cystic component and enhancement pattern.Desmo-plastic development(plasticity growth) is significant feature of cerebro-ventricular ependymomas.Awareness of these difference is in favor of correct preoperative diagnosis.