 Compared to 12/10/2015, there is interval decrease in the size of some of the cystic components of the craniopharyngioma. The cystic component involving the left prepontine cistern demonstrates decrease in size from approximately 12 x 14 mm to 5 x 9 mm. There is improvement in mass effect on the left aspect of the pons. Previously seen fluid level within this component is no longer appreciated. In the right ambient cistern, a cystic component with T1 hyperintensity measures 10 x 10 mm which is overall not significantly changed in size however there is susceptibility effect and increased areas of T1 hyperintensity compatible with evolution of blood products and perhaps component of proteinaceous material. There is no new mass effect. There continues to be involvement of the prepontine, cerebellopontine angle, right ambient and right quadrigeminal cisterns, as well as the right middle cranial fossa, with associated mass effect upon the brainstem, right medial temporal lobe, and hypothalamus-optic apparatus complex. No enlarging enhancing component. Leftward displacement of the pons and contour deformity involving the right lateral aspect of the midbrain is not significantly changed. There is unchanged volume loss of the left cerebellar hemisphere associated with increased T2 signal, which may be attributable to crossed cerebellar diaschisis versus chronic injury. The basilar artery is tortuous and encased by the tumor. There is stable position of right transfrontal catheter with the tip in the right prepontine cyst. The ventricular system appears to be unchanged. There are foci of susceptibility effect within the right temporal lobe resection cavity, consistent with hemosiderin deposition, and within portions of the tumor particularly in the suprasellar cistern, which likely represent calcifications.
Compared to 12/10/2015, there is further regression of some of the peripheral cystic components of the complex suprasellar and posterior fossa craniopharyngioma, particularly in the left prepontine region where there is associated improvement in mass effect. 