title: Validation of FDG-PET/MRI coregistration in nonlesional refractory childhood epilepsy.
abstract: OBJECTIVE
  To validate the use of 18F-fluorodeoxyglucose-positron emission tomography/magnetic resonance imaging (FDG-PET/MRI) coregistration for epileptogenic zone detection in children with MRI nonlesional refractory epilepsy and to assess its ability to guide a second interpretation of the MRI studies.
  
  
  METHODS
  Thirty-one children with refractory epilepsy whose MRI results were nonlesional were included prospectively. All patients underwent presurgical evaluation following the standard protocol of our epilepsy unit, which included FDG-PET and FDG-PET/MRI coregistration. Cerebral areas of decreased uptake in PET and PET/MRI fusion images were compared visually and then contrasted with presumed epileptogenic zone localization, which had been obtained from other clinical data. A second interpretation of MRI studies was carried out, focusing on the exact anatomic region in which hypometabolism was located in FDG-PET/MRI fusion images.
  
  
  RESULTS
  Both FDG-PET and FDG-PET/MRI detected hypometabolism in 67.8% of patients, with good concordance on a subject basis and on the cerebral region involved (κ statistic = 0.83 and 0.79, respectively). Hypometabolism detected by single PET, as well as by PET/MRI fusion images, was located in the same hemisphere, as indicated by electroclinical data in 58% of patients, and at the same place in 39% of cases. Of the patients who showed hypometabolism on PET/MRI, 43% also experienced changes in the guided second MRI interpretation, from nonlesional to subtle-lesional.
  
  
  CONCLUSIONS
  PET/MRI coregistration is an imaging variant that is at least as accurate as PET alone in detecting epileptogenic zone in pediatric nonlesional patients, and can guide a second look at MRI studies previously reported as nonlesional, turning a meaningful percentage into subtle-lesional.
authors: Department of Nuclear Medicine, Hospital Clinic, Barcelona, Spain. s.rubi.sureda@gmail.com
authors: Sebastià
authors: S
authors: Rubí
authors: Xavier
authors: X
authors: Setoain
authors: Antonio
authors: A
authors: Donaire
authors: Núria
authors: N
authors: Bargalló
authors: Francesc
authors: F
authors: Sanmartí
authors: Mar
authors: M
authors: Carreño
authors: Jordi
authors: J
authors: Rumià
authors: Anna
authors: A
authors: Calvo
authors: Javier
authors: J
authors: Aparicio
authors: Jaume
authors: J
authors: Campistol
authors: Francesca
authors: F
authors: Pons
mesh_terms: D000293:Adolescent; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D001931:Brain Mapping; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography / Q000379:methods; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D014741:Video Recording
chemical_list: D019788:Fluorodeoxyglucose F18