Clinical question: Intraop ablation. Signs and symptoms: Intraop ablation. Pre- and postenhanced treatment planning MRI:Study is performed utilizing treatment planning protocol and is not a true diagnostic exam.Examination redemonstrates a tectal plate mass with a thick rim of enhancement and measuring approximately 21 x 21 mm in transaxial dimensions.The lesion demonstrates a defect within its posterior right lateral rim likely secondary to ablation. There is a large central necrosis which is new since prior exam from 4-29-50.The mass demonstrates slight interval increased size since prior study which could be treatment related. Severely dilated supratentorial ventricular system demonstrate no appreciable interval change.Small CSF signal intensity right hemispheric subdural collection demonstrate no appreciable change since prior exam. No detectable new foci of abnormal parenchymal or leptomeningeal enhancement.
1.Interval significant central necrosis of a tectal plate tumor and a defect along its left posterior wall believed to be secondary to ablation.2.The tumor measures 21 x 21 mm in transaxial dimensions which is slightly larger than prior study and likely treatment related.3.Stable enlarged supratentorial ventricular system.