Clinical question: History of GBM, status post chemotherapy RT, surveillance MRI. Signs and symptoms: None. Pre and postcontrast enhanced brain MRI:Negative diffusion-weighted images.Examination demonstrates significant interval improvement in postoperative changes of a large right anterior frontal and temporal craniotomy since prior exam.There is interval complete resolution of subgaleal CSF density collection over the craniotomy flap likely secondary to CSF leakage since prior exam. Extra-axial serosanguineous collection along the inner table of the surgical flap in the right frontal lobe is within expected postop change and measures approximately at maximum of 9.5 mm thickness. There is also overlapping pleural thickening with enhancement also within expected postop change.A well-demarcated CSF signal intensity surgical cavity in the right anterior/inferior frontal lobe measures approximately at 33 x 61 mm and with interval decreased size since prior study.There is mild surrounding FLAIR hyperintensity suggestive of residual edema or gliosis.There is a thin and uniform enhancement of the surgical cavity wall with significant interval improvement since prior exam. There is no convincing evidence of residual tumor on this exam at this time. Further follow-up is needed to exclude recurrence.Lateral ventricles are slightly prominent however without interval change or deviation of the midline. Revisualization of a chronic retention cyst in the sphenoid sinus.
1.No acute intracranial process.2.Interval improvement of postoperative changes of right anterior frontal lobe with decreased size of surgical cavity and interval decreased enhancement along the surgical cavity wall as detailed above. No convincing evidence of residual tumor.3.Interval complete resolution of right frontal subgaleal fluid collection over the craniotomy flap since prior study.4.Epidural collection along the inner table of craniotomy flap measuring maximum of 7.5 mm in thickness. Overlapping dural thickening with enhancement which is inseparable from the surgical cavity.