From our surgical epilepsy imaging database, we selected 15 consecutive patients undergoing presurgical evaluation for drug-resistant focal epilepsy with radiologically apparent (MRI positive) or histologically proven (MRI positive or MRI negative) focal cortical dysplasia who had available 3T MRI structural imaging carried out at the NIH Clinical Center with our standard epilepsy imaging protocol between 2014 and 2019.  Patients scanned on a different scanner or with a different imaging protocol were excluded, as were subjects with low image quality or other image artifacts on visual inspection. Data from a control group of 30 healthy volunteers with no previous history of neurologic, psychiatric or other significant medical illnesses that may affect the central nervous system were also included. Data were collected at the Clinical Center of the National Institutes of Health (NIH; Bethesda, MD). All participants were enrolled in a research protocol approved by the Institutional Review Board; informed consent was obtained from all participants.