Cerebral cysts [348.0], Reason for Study: ^Reason: history of arachnoid cyst. Please eval for recurrence. No evidence of acute ischemic or hemorrhagic lesion on the scan.Redemonstration of suboccipital craniectomy and C1 laminectomy status.The retro cerebellar arachnoid cyst is again shown. The maximum diameter of the arachnoid cyst is 30.4mm (AP) x 78.1mm (Craniocaudal) x 42.5mm (Right to left) which does not show any significant interval change since prior scan.The ventricles, sulci and cisterns are symmetric and unremarkable. The gray-white matter differentiation is normal. There is no abnormal/unusual enhancement.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 decompressive suboccipital craniectomy and C1 laminectomy status.2. No change of retro cerebellar subarachnoid cyst in terms of size and MR signal intensity since prior scan.3. No acute ischemic or hemorrhagic lesion. No abnormal enhancement.