 There is a stable right frontal approach Ommaya catheter with mild associated susceptibility artifact. The tip is located in the posterior left frontal horn. Corresponding to the area of abnormal low density in the right frontal lobe, there is extensive T2/FLAIR hyperintensity, again significantly enlarged since the most recent MRI of 12/19/2015. This remains vasogenic pattern. There is mild localized mass effect on the anterior right lateral ventricle as well as overlying sulci.The ventricles and sulci are otherwise within normal limits. The cisterns remain patent. There is no midline shift. There are no areas of pathological enhancement. No definite leptomeningeal enhancement is appreciated. There is no diffusion abnormality. 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 severe fluid opacification of the right mastoid air cells
1.Prominent area of T2/FLAIR hyperintensity in the right frontal subcortical and deep white matter along the right frontal approach Ommaya catheter tract corresponding to low-density abnormality on CT, without associated enhancement. This again appears vasogenic in pattern with preservation of cortex, with localized mass effect. Again, the area of T2 abnormality is significantly progressed since that of the 12/19/2015 MRI. Please evaluate for catheter dysfunction, especially in relation to most recent chemotherapy administration of 12/22/2015.2.No definite leptomeningeal enhancement appreciated.3.Severe right mastoid air cell fluid opacification which is nonspecific. Please correlate clinically.