Clinical question: History of epilepsy status post ablation. Signs and symptoms: Surveillance scan of ablation. Pre-and post-enhanced brain MRI:No diffusion weighted abnormality.Examination demonstrates a focus of T2/flair hyperintensity along the mesial aspect of right temporal lobe with evidence of internal susceptibility signal changes (blood product) representing the site of tracer activation. This focus measures approximately 23 mm in AP axis and 7-mm in transverse axis measured on axial T2 series 4 image 11. There is slight dilatation (ex vacuo) of the tip of right temporal horn adjacent to this finding. A thin linear band of susceptibility extends from this region posteriorly two right posterior temporal calvarium likely representing the track of previously removed DBS.Similar susceptibility linear changes are also noted extending from the medial aspect of the left temporal lobe posteriorly to the left posterior temporal -- occipital inner table of skull. Additional smaller similar finding is in the right frontal lobe extending from right frontal horn to the inner table of the skull. There is significant interval improvement of this finding since prior exam. There is residual tiny focus of flair hyperintensity representing small focus of encephalomalacia.There is generalized mild prominence of cortical sulci for patient's stated age of 21 without change since prior exams.There is also mild prominence of lateral ventricles without change since prior study. Post-enhanced images demonstrate patchy rim enhancement along the sites of right mesial temporal laser ablation. Compared to prior exam there is suggestion of interval decreased size of lesion a combination and the decreased extent of enhancement indicating interval improvement. There is also significant two near complete resolution of rim enhancement in the right frontal lobe at the level of the burr hole for surgical approach.Post-enhanced images also demonstrate a tiny left frontal developmental venous anomaly.
1.Small focus of hemorrhagic encephalomalacia in the mesial aspect of right temporal lobe at the site of laser ablation with patchy linear enhancement which demonstrates interval improvement since prior exam.2.Interval resolution of focus of enhancement in the right frontal lobe under a frontal burr hole representing track of surgical approach.3.Multiple tracts of hemosiderin deposition along the previously placed and removed DBS electrode and laser ablation device.