 Comparing to more remote exams, there again does not appear to be significant change in the appearance of the diffuse nonenhancing bilateral hypothalamic-optic glioma allowing for differences in technique, as current orbital images are somewhat degraded by patient motion. The suprasellar CSF signal intensity collection with greater right paramedian prominence has further increased in size, now measuring 23 mm AP x 17 mm CC compared to previous measurement of 20 mm AP x 18 mm CC on sagittal images. This appears contiguous with the right lateral ventricle on 501/16. There is persistent mass effect upon the underlying tectum which again was previously thickened. No definite abnormal signal is seen within the tectum. There is stable focal effacement of the aqueduct of Sylvius associated with stable lateral and third ventricular dilatation as well as periventricular T2/FLAIR hyperintensity likely relating to chronic transependymal CSF flow. There is stable T2 hyperintensity along the previous right transfrontal surgical tract, likely related to prior endoscopic third ventriculostomy. The floor the third ventricles not well delineated, although on CSF flow imaging there appears to be a small area of biphasic CSF flow through the expected location of the third ventriculostomy into the prepontine region. There are stable foci of non-enhancing T2 hyperintensity in the anterior left frontal lobe and cerebellar white matter which are nonspecific, although the cerebellar findings likely represent FASI of NF-1. There is no diffusion abnormality or extra-axial collection.There is slight increased CSF space at the level of the crowded foramen magnum and surrounding the slightly pointed cerebellar tonsils, with slightly improved biphasic CSF flow along the dorsal aspect of the foramen magnum. There appears to be slight decreased dorsal convexity of the mildly T2/STIR hyperintense cervicomedullary mass, which now measures 16 mm AP compared to prior 17 mm on the 3-D T2 weighted images. On sagittal STIR imaging, the ill-defined lesion appears similar the prior dedicated cervical spine imaging. Mild retroflexion of the dens with platybasia also contributes to the above narrowing.
1.Slight further increased size of CSF signal intensity collection in the supracerebellar location with slight right paramedian extension, which appears contiguous with the right lateral ventricle. Continued mass effect upon the underlying tectum, previously noted to be thickened although without abnormal signal.2.Stable dilatation of the lateral and third ventricles, with suggestion of biphasic CSF flow through the expected location of the third ventriculostomy.3.Stable appearance of bilateral diffuse hypothalamic optic glioma.4.Subtle improved CSF space and biphasic CSF flow at the level of the crowded foramen magnum with slightly pointed cerebellar tonsils with underlying expansile cervicomedullary mass appearing slightly decreased in dorsal convexity on comparison of 3-D T2 weighted images, although this may relate to differences in patient head positioning.