title: The interactive electrode localization utility: software for automatic sorting and labeling of intracranial subdural electrodes.
abstract: OBJECTIVE
  Existing methods for sorting, labeling, registering, and across-subject localization of electrodes in intracranial encephalography (iEEG) may involve laborious work requiring manual inspection of radiological images.
  
  
  METHODS
  We describe a new open-source software package, the interactive electrode localization utility which presents a full pipeline for the registration, localization, and labeling of iEEG electrodes from CT and MR images. In addition, we describe a method to automatically sort and label electrodes from subdural grids of known geometry.
  
  
  RESULTS
  We validated our software against manual inspection methods in twelve subjects undergoing iEEG for medically intractable epilepsy. Our algorithm for sorting and labeling performed correct identification on 96% of the electrodes.
  
  
  CONCLUSIONS
  The sorting and labeling methods we describe offer nearly perfect performance and the software package we have distributed may simplify the process of registering, sorting, labeling, and localizing subdural iEEG grid electrodes by manual inspection.
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA. aestrivex@gmail.com.|Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 13th Street, Charlestown, MA, USA. aestrivex@gmail.com.
authors.forename: Roan A
authors.identifier: http://orcid.org/0000-0002-5309-1036
authors.initials: RA
authors.lastname: LaPlante
authors.affiliation: Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.|Department of Radiology, Harvard Medical School, Boston, MA, USA.
authors.forename: Noam
authors.initials: N
authors.lastname: Peled
authors.affiliation: Cortical Physiology Laboratory, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Deborah I
authors.initials: DI
authors.lastname: Vallejo
authors.affiliation: Cortical Physiology Laboratory, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Mia
authors.initials: M
authors.lastname: Borzello
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Darin D
authors.initials: DD
authors.lastname: Dougherty
authors.affiliation: Department of Neurological Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Emad N
authors.initials: EN
authors.lastname: Eskandar
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.|Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA.
authors.forename: Alik S
authors.initials: AS
authors.lastname: Widge
authors.affiliation: Cortical Physiology Laboratory, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Sydney S
authors.initials: SS
authors.lastname: Cash
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.|Department of Radiology, Harvard Medical School, Boston, MA, USA.|Harvard-MIT Health Sciences and Technology, Cambridge, MA, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Stufflebeam
mesh_terms: D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging*; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000295:instrumentation*; D004827:Epilepsy / Q000175:diagnosis*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D012372:ROC Curve; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: CT; Electrocorticography; Image registration; MRI; Software