Neoplasm of unspecified behavior of unspecified site [D49.9], Reason for Study: ^Reason: preop planning for tumor resection. History: brain tumor Multiple fiducial markers are attached on scalp.There is about 50mm x 46.7mm x 48.4mm sized mixed cystic and solid posterior fossa mass located at 4th ventricle inferior aspect. There is no evidence of adjacent brain edema but shows mass effects toward 4th ventricle and cerebellar vermis. The 4th ventricle is obliterated and there are evidence of ventriculomegaly.The enhancement is slightly inhomogeneous on solid portion. There is no evidence of peripheral enhancement of cystic portion.Constellation of these findings indicate series of differential diagnosis of ependymoma, hemangioblastoma, medulloblastoma, glioblastoma, metastasis, and choroid plexus papilloma. The midline structures and cranial-cervical junction are normal. Normal flow voids are identified in the major intracranial vessels. The paranasal sinuses and mastoid air cells are clear.
About 50mm x 48mm x 49mm sized posterior fossa, mainly 4th ventricular mixed solid and cystic enhancing mass as described above.Differential diagnosis include ependymoma, hemangioblastoma, medulloblastoma, glioblastoma, metastasis, and choroid plexus papilloma. 