Clinical question: 14-year-old with history of glioblastoma multiforme status post 42 days of radiation and adjunctive chemotherapy. Signs and symptoms: Brain tumor. Pre-and post-enhanced brain MRI:Negative diffusion weighted series.Examination demonstrates significant interval decrease in edema since prior exam surrounding a left posterior temporal -- parietal surgical cavity. Small residual flair hyperintensity at the site surrounding the surgical cavity still persist. There is interval better visualization of adjacent cortical sulci and the left lateral ventricle secondary to decreased mass effect.There is also interval decreased size of the surgical cavity which demonstrate CSF signal intensity and measuring at 27 x 18-mm compared to prior study measurement of 34 x 28. The surgical cavity is well demarcated and demonstrate a very thin partial enhancement along its medial wall which appears to be contiguous with the trigone of left lateral ventricle. There is a small more nodular focus of enhancement at the site of attachment of surgical cavity with the trigone of left lateral ventricle as well as a second additional small focus of enhancement within the trigone. Findings could represent postoperative changes and a focus of enhancement in the trigone as well could represent a focus of choroid plexus. Further follow-up is holder is needed for better assessment. Enhancement along the inner wall of the surgical cavity has decreased since prior exam. There is also complete resolution of enhancement of the ependymal lining of the trigone and the occipital horn of left lateral ventricle since prior study. Ventricular system remain within normal size and without addition of midline.Postoperative changes of a left craniotomy and a small CSF signal intensity extra-axial collection demonstrates subtle interval decreased size.
1.Significant interval decreased peri-surgical vasogenic edema of the left posterior temporal, occipital and parietal lobe since prior exam.2.Interval decreased size of surgical cavity in left posterior temporal -- parietal with CSF signal intensity content.3.A thin band of enhancement along the medial wall of the surgical cavity extends from the trigone of left lateral ventricle to the inner table of skull and likely representing post surgical change. A tiny focus of enhancement within the left trigone is also noted. Enhancements at this sites are suggestive of post treatment /surgical change however further follow up is needed to entirely exclude possibility of residual tumor.4.Complete resolution of previously noted enhancement of the ependymal lining of the left trigone and occipital horn of lateral ventricle.