From palliative care to successful resection: The value of stereoelectroencephalography patterns in two cases of MRI-negative epilepsy within eloquent language areas

Background Surgical management of MRI-negative drug-resistant epilepsy (DRE) in the eloquent language cortex poses a significant challenge. The absence of a clear structural lesion on MRI often leads to palliative rather than curative treatment approaches. This case report highlights the critical role of specific stereoelectroencephalography (SEEG) patterns in guiding successful resective surgery in this high-stakes scenario. Case Presentation: We present the cases of two patients with MRI-negative DRE localized to Broca's area and Wernicke's area, respectively. Following non-diagnostic non-invasive evaluations, SEEG monitoring was performed. In both cases, the SEEG revealed characteristic interictal patterns highly suggestive of focal cortical dysplasia type II (FCD II), including continuous rhythmic spiking and sleep-wake cycle modifications. Based on these definitive electrophysiological findings, the patients underwent awake resection with intraoperative monitoring. Histopathological examination confirmed FCD Type II in both instances. Conclusion These cases demonstrate that a distinct SEEG signature can reliably indicate an underlying FCD II, even in MRI-negative epilepsy involving critical language areas. This finding can empower clinicians to pursue potentially curative resective surgery with an excellent prospect of seizure freedom and functional preservation. The identification of these SEEG characteristics is, therefore, pivotal in the surgical decision-making algorithm for similar complex cases.