10-year-old female with ventriculomegaly, optic nerve gliomas, Chiari malformation, experiencing headaches. The patient is status post third ventriculocisternostomy. There is no significant interval change in the diffuse bilateral hypothalamic-optic glioma. A CSF intensity collection in a supra-vermian location, extending in the right paramedian direction, has increased over the interim with compared to the most recent MRI, now measuring up to 20 mm in maximal dimension (previously 7 mm). When compared to the more recent head CT, this is unchanged. This causes mass effect upon the underlying tectum, which previously demonstrated a thickened appearance.T2 hyperintensity is again noted surrounding a prior right transfrontal surgical track, likely related to prior endoscopic third ventriculostomy. As before, no defect is discernable in the floor of the third ventricle and no CSF jet is apparent in the third ventricle. The lateral and third ventricles have slightly increased by approximate 3 mm in maximal width when compared to the most recent MRI, however unchanged when compared to the more recent head CT.There is stable effacement of the aqueduct of Sylvius associated with enlargement of the lateral and third ventricles as well as periventricular T2 hyperintensity that may represent transependymal CSF flow, unchanged in extent. There are stable foci of non-enhancing T2 hyperintensity in the anterior left frontal lobe and cerebellar white matter without interval formation of new hyperintensities. There is no evidence of intracranial hemorrhage or acute infarct. Redemonstrated is mild retroflexion of the dens, platybasia, and extension of the cerebellar tonsils inferior to the level of the foramen magnum with pointed morphology. There is unchanged constriction of CSF flow across the anterior foramen magnum due to the retroflexed dens, although CSF flow is again evident across the posterior foramen magnum and at the level of the circle of tonsils. Previously demonstrated scattered paranasal sinus mucosal thickening has resolved. Mastoid air cells are clear.
1.A CSF intensity collection in a supra-vermian location, extending in the right paramedian direction, has increased over the interim with compared to the most recent MRI, now measuring up to 20 mm in maximal dimension (previously 7 mm). When compared to the more recent head CT, this is unchanged. This causes mass effect upon the underlying tectum, which previously demonstrated a thickened appearance.2.The lateral and third ventricles have slightly increased by approximate 3 mm in maximal width when compared to the most recent MRI, however unchanged when compared to the more recent head CT.