| Institution: | 1. Laboratory of Children’s Brain Dynamics, Division of Newborn Medicine, Department of Medicine, Boston Children''s Hospital, Harvard Medical School, Boston, MA, USA;2. Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, University Campus Bio-Medico of Rome, Rome, Italy;3. The Hillingdon Hospital NHS Foundation Trust, London, UK;4. Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA;5. Jane and John Justin Neurosciences Center, Cook Children''s Health Care System, Fort Worth, TX, USA;6. Division of Epilepsy Surgery, Department of Neurosurgery, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA;7. School of Medicine, Texas Christian University and University of North Texas Health Science Center, Fort Worth, TX, USA;8. Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA |
| Abstract: | ObjectiveTo assess whether ictal electric source imaging (ESI) on low-density scalp EEG can approximate the seizure onset zone (SOZ) location and predict surgical outcome in children with refractory epilepsy undergoing surgery.MethodsWe examined 35 children with refractory epilepsy. We dichotomized surgical outcome into seizure- and non-seizure-free. We identified ictal onsets recorded with scalp and intracranial EEG and localized them using equivalent current dipoles and standardized low-resolution magnetic tomography (sLORETA). We estimated the localization accuracy of scalp EEG as distance of scalp dipoles from intracranial dipoles. We also calculated the distances of scalp dipoles from resection, as well as their resection percentage and compared between seizure-free and non-seizure-free patients. We built receiver operating characteristic curves to test whether resection percentage predicted outcome.ResultsResection distance was lower in seizure-free patients for both dipoles (p = 0.006) and sLORETA (p = 0.04). Resection percentage predicted outcome with a sensitivity of 57.1% (95% CI, 34–78.2%), a specificity of 85.7% (95% CI, 57.2–98.2%) and an accuracy of 68.6% (95% CI, 50.7–83.5%) (p = 0.01).ConclusionIctal ESI performed on low-density scalp EEG can delineate the SOZ and predict outcome.SignificanceSuch an application may increase the number of children who are referred for epilepsy surgery and improve their outcome. |
