 Again seen are postsurgical changes including suboccipital craniectomy and resection of the posterior arch of C1. The CSF space remains well expanded at this level and the cerebellar tonsils are neither crowded nor peglike. CSF flow is seen through both the anterior and posterior aspects of the foramen magnum, similar to prior. Minimal scarring is again evident involving the posterior inferior aspect of the cerebellar surface. No evidence of tumor recurrence at the site of prior tumor dorsal to the medulla.No evidence of parenchymal edema, mass, or mass effect is seen. No evidence of ischemia or hemorrhage. The ventricular system is normal in caliber and morphology. No abnormal parenchymal or meningeal enhancement is seen.CERVICAL SPINE
1. Postoperative changes related to resection of exophytic tumor along the posterior aspect of the medulla. No evidence of tumor recurrence.2. Postoperative changes related to lipomyelomeningocele repair and prior cord untetherings. No significant change in appearance of the conus which appears to adhere to the dorsal dural surface and demonstrates no ventral motion with prone imaging. Extensive adhesions within the distal thecal sac are also evident and unchanged. Re-tethering is again not excluded and can be correlated with clinical findings. No new cord signal abnormality or syrinx.