Male, 41 years old, with anaplastic astrocytoma, follow-up exam. Again seen are sequelae of right frontal craniotomy and right frontal lobe surgery for tumor resection. Heterogeneous extradural and probable subdural collections along the craniotomy flap have not significantly changed from the prior examination. A thick rim of enhancement along the periphery of these collections, best seen on delayed postcontrast images, likely represents granulation and is not significantly changed.The right frontal lobe is severely encephalomalacic. The right frontal horn shows ex vacuo dilatation, more pronounced than on the prior exam. T2 hyperintensity and gyral thickening within the inferior right frontal gyri are not significantly changed when compared to the prior two examinations. T2 hyperintensity within the right middle and superior frontal gyri is slightly progressed from the exam of 11/10/2014, but similar to that seen on 7/12/2014. A small focus of white matter T2 hyperintensity along the posterior right lateral ventricle body is new.T2 hyperintensity and thickening of the genu of the corpus callosum, with some associated diffusion restriction appears similar to the prior exam of 11/10/2014, and improved when compared to 7/12/2014. T2 hyperintensity extending into the left periventricular white matter has progressed when compared to both prior exams.Single and multi voxel spectroscopy was performed on the areas of signal abnormality surrounding both the left and right frontal horns. No unequivocally suspicious choline elevation is seen, and most voxels show either benign or nonspecific metabolite patterns. rCBV mapping was also performed which shows low blood volume correlating to most of the periventricular T2 hyperintense regions. Some elevated blood volume is suspected within the far anterior left frontal lobe but this is of uncertain significance as the parenchyma in this region does not appear thickened or infiltrated.No evidence of pathologic parenchymal enhancement is seen. No new mass effect is detected. Apart from progressive ex vacuo dilatation of the right frontal horn, the ventricular system is not significantly changed.
1.Demonstration of extensive postoperative findings related to prior right frontal tumor resection.2.T2 hyperintensity within the white matter surrounding the right frontal horn, as well as more posteriorly along the body of the right lateral ventricle, and along the left frontal horn, has progressed compared to the immediate prior examination. There is no associated enhancement in these areas. Spectroscopy and rCBV mapping of this tissue show no definite concerning features. As such, this may simply represent treatment effect with progressive tumor considered less likely.3.Abnormal signal and thickening of the genu of the corpus callosum is similar to that seen on the prior exam, and is improved relative to older studies.