 Images were obtained for surgical stereotactic localization purposes. Postoperative changes are seen from previous occipital craniectomy. There is redemonstration of a large cystic lesion in the midline posterior fossa, slightly greater to the left side, with areas of enhancing mural nodularity and small serpentine flow-voids. It measures 4.5 cm transverse x 5.0 cm AP x 3.9 cm CC. When allowing for differences in technique, it appears slightly increased in size compared to prior outside MRI. There is mild increased degree of mass effect upon the fourth ventricle, with persistent areas of T2 hyperintensity extending outward into the cerebellar parenchyma, slightly progressed and representing vasogenic edema. A linear area of T2 hyperintensity the right frontal lobe is likely postprocedural gliosis.Areas of solid nodular enhancement associated with the dominant lesion as well as other scattered foci of nodular enhancement elsewhere in the cerebellum bilaterally appear grossly similar. There is a rounded area of nodularity along the dorsal aspect of the right posterior body of the corpus callosum, measuring 7 x 7 mm in greatest axial dimensions.In addition, along the upper cervical spinal canal at the C1-C2 level, there is an irregular enhancing intradural extra medullary nodule along the left ventral thecal sac on 4/9 measuring 6 x 7 mm, with slight thickening of the adjacent dural margin just caudally. Coronal and axial T2-weighted images appear to suggest mild heterogeneous T2 hyperintense signal within the right greater than left atrophic cord along the visualized upper cervical spine. Previous spine imaging suggested myelomalacia at these levels with associated volume loss.The ventricles and sulci are otherwise within normal limits. The cisterns remain patent. There is no midline shift or mass effect. No extra-axial fluid collection is identified.Normal flow-voids are demonstrated in the major intracranial vascular structures. The midline structures and craniocervical junction are within normal limits. There is minimal opacification of posterior ethmoid air cells.
1. Slight interval increased size of dominant cerebellar hemangioblastoma with increased mass effect although without significant interval ventricular size change.2. Similar pattern of other scattered smaller predominantly cerebellar enhancing nodules as well as one posterior to the posterior body of the corpus callosum on the right side, also likely hemangioblastomas.3. Findings suggestive of upper cervical cord myelomalacia of the incompletely assessed, with the possibility of intrinsic cord lesion entirely excluded on the basis of this exam. Small nodular area of enhancement along the left ventral thecal sac at the C1-C2 level, likely representing an additional hemangioblastoma perhaps along the cervical nerve root. Grossly, this appears similar to prior outside MRI of the spine from May 2012.