Other specified disorders of brain [G93.89], Reason for Study: ^Reason: evaluate for residual tumor History: s/p posterior fossa tumor resection Redemonstration of post resection findings of the posterior fossa lesion including occipital craniotomy site suboccipital fluid collections, residual air within 4th ventricle, some blood products and dilated but much improved ventricular system, unchanged since prior scan.Nodular and somewhat linear shaped enhancing lesions seen on prior scan at the superior and posterior aspect of the resection cavity are again seen on this scan, unchanged since prior. Diagnostic possibilities including focal residual tumor and adjacent venous structures. Follow up imaging is recommended.There is no evidence of another abnormal enhancing lesion on this scan.There is no evidence of acute ischemic or hemorrhagic lesion. The ventricles, sulci and cisterns are dilated but unchanged since prior scan. The midline structures and cranial-cervical junction are normal except about 5.8mm downward herniation of cerebellar tonsils which is unchanged since prior scan. Normal flow voids are identified in the major intracranial vessels. The paranasal sinuses and mastoid air cells are clear.
1. Redemonstration of focal nodular and somewhat linear enhancing lesions on the superior and posterior aspect of the posterior fossa lesion resection cavity as described above, unchanged since prior scan.2. Postoperative no unusual finding.3. No evidence of new abnormal enhancing lesion. No acute ischemic or hemorrhagic lesion.