18-year-old female with Chiari malformation, now experiencing neck pain and headache, status post the compression. Brain: There has been interval repositioning of a fourth ventricular shunt now extending from the level of the dura, into the fourth ventricle, terminating within the cerebral aqueduct. The fourth ventricular height measured in the midline is decreased from 15 to 13 mm. Overlying the dura, there is a a larger post procedural fluid collection measuring 25 mm transverse x 35 mm AP x 65 mm craniocaudal, without significant mass effect upon the adjacent dura. There has been increase in both lateral and third ventricular sizes, the former measuring 38 mm (previously 32 mm), and the latter measuring 6 mm (previously 2 mm), as measured on coronal T2 imaging at the level of the foramen Monroe.Redemonstrated are postoperative findings related to Chiari decompression. Mild deformity of the posterior inferior cerebellum and medulla associated is unchanged. There is slightly more biphasic CSF flow noted posteriorly at the level of the cerebellar tonsils. There is no evidence of acute intracranial hemorrhage, mass, or acute infarct. The ventricles and basal cisterns are unchanged in size and configuration. There is no midline shift or herniation. Expected vascular flow-voids are demonstrated. The paranasal sinuses and mastoid air cells are clear.Cervical Spine: There is no evidence of syringohydromyelia. The vertebral body heights are preserved. There is no significant spinal canal or neural foraminal stenosis. The vertebral bone marrow signal is unremarkable. The vertebral column alignment is unchanged with mild retroflexion of the dens and lack of the usual lordosis. There appears to be a left thyroid nodule.
1.There has been interval repositioning of a fourth ventricular shunt now extending from the level of the dura, into the fourth ventricle, terminating within the cerebral aqueduct. The fourth ventricular height measured in the midline is decreased from 15 to 13 mm. There has been increase in both lateral and third ventricular sizes. Overlying the dura, there is a a larger post procedural fluid collection measuring 25 mm transverse x 35 mm AP x 65 mm craniocaudal, without significant mass effect upon the adjacent dura. There is slightly more biphasic CSF flow noted posteriorly at the level of the cerebellar tonsils. 2.There is no evidence of syringohydromyelia.