Headache(784.0) [784.0] / Other conditions of brain(348.89) [348.89] / Malignant neoplasm of colon, unspecified site [153.9], Reason for Study: ^Reason: assess posterior fossa resection History: Brain tumor, HA There is evidence of suboccipital midline craniectomy.Previously shown the acromion intra-axial mass has been resected. There is no evidence of residual mass except minimal enhancement of the margin of resection cavity which likely represent post surgical excision reactive enhancement instead of residual mass.There are local minimal scattered postoperative blood products with minimal edema indicating post operative status. Comparing to previous of MRI, surrounding edema on bilateral cerebellar hemisphere and left middle cerebral peduncle appears to be decreased on the scan.There is also irregular shaped low signal intensity on T1 and T2 weighted image with susceptibility artifacts on the resection cavity which likely represent postoperative local block products but could also be associated air.Ventricular system remains normal size without evidence of ventriculomegaly.There is no evidence of acute ischemic or hemorrhagic lesion except surgical bed minimal blood products.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.
1. Post midline suboccipital craniectomy status with near total or total removal of superior paramedian intra-axial mass. Minimal local blood products are likely related to surgery.2. Irregular shaped low signal intensity lesion on anterior superior aspect of resection cavity indicating local blood products and or associated introduced air.3. No evidence of acute ischemic or hemorrhagic lesion except resection area blood products.4. Minimal enhancement of margin of the resection cavity likely represent reactive enhancement.