Abstracts

Rationale: Focal Cortical Dysplasia (FCD) is a common malformation of cortical development and one of the most common etiologies of intractable epilepsy in pediatric and adult population. Many of these patients fail multiple AEDs and often undergo surgical evaluation, including multiple MRIs [1, 2]. We are investigating the relationships between chronological MRI changes, eventual location of pathological findings, and surgical outcomes in these patients. Methods: Reviewing chronological MRI changes, final pathology, and eventual surgical outcomes in patients with FCD who underwent epilepsy surgery at our institution since 2016. Results: Total of eight FCD cases were reviewed. 2/8 cases were associated with interval cystic changes on MRI and prominent reactive astrogliosis on pathology. Both cases were from left frontal lobe onset and resulted in Engel IIB outcome. 4/8 cases with only typical MRI findings of FCD were found to have no or mild reactive astrogliosis and better surgical outcome at Engel IA-ID. These cases were from right frontal or temporal lobe origin. Finally, 2/8 cases which did correlate with normal MRI showed poor surgical outcome, one of which was associated with dual pathology of FCD and meningioencephalitis. Cystic-like changes in MRI became conspicuous after an average of 184 months. Stable FCD MRI changes over an average of 74.5 months, corresponded with better surgical outcome. Negative MRIs of 8 month interval with FCD pathologically proven cases correlated relatively with lower surgical outcome. Conclusions: Chronological MRI changes in our two cases corresponded to prominent reactive astrogliosis and relative good surgical outcome. It is unclear if these findings have any surgical predictor value. It has been documented that certain MRI findings may correlate with surgical outcomes [3]. The location of these lesions has also been discussed. In our small series, the right hemispheric lesions have relative better surgical outcome. In our small series, all cases with no or mild reactive gliosis had the best surgical outcome. The worst surgical outcome was in the cases of normal MRIs. The significance of lateralization is currently unknown but may impact surgical planning. Overall, FCD have a good surgical outcome (Engel I-II) in 6/8 patients. Funding: No funding