title: DTI of tuber and perituberal tissue can predict epileptogenicity in tuberous sclerosis complex.
abstract: OBJECTIVE
  To evaluate whether diffusion tensor imaging (DTI) can predict epileptogenic tubers by measuring apparent diffusion coefficient (ADC), fractional anisotropy, axial diffusivity, and radial diffusivity in both tubers and perituberal tissue in pediatric patients with tuberous sclerosis complex (TSC) undergoing epilepsy surgery.
  
  
  METHODS
  We retrospectively selected 23 consecutive patients (aged 0.4-19.6 years, mean age of 5.2; 13 female, 10 male) who underwent presurgical DTI and subsequent surgical resection between 2004 and 2013 from the University of California-Los Angeles TSC Clinic. We evaluated presurgical examinations including video-EEG, brain MRI, (18)F-fluorodeoxyglucose-PET, magnetic source imaging, and intraoperative electrocorticography for determining epileptogenic tubers. A total of 545 tubers, 33 epileptogenic and 512 nonepileptogenic, were identified. Two observers generated the regions of interest (ROIs) of tubers (ROI(tuber)), the 4-mm-thick ring-shaped ROIs surrounding the tubers (ROI(perituber)), and the combined ROIs (ROI(tuber+perituber)) in consensus and calculated maximum, minimum, mean, and median values of each DTI measure in each ROI for all tubers.
  
  
  RESULTS
  The Mann-Whitney U test demonstrated that the epileptogenic group showed higher maximum ADC and radial diffusivity values in all ROIs, and that maximum ADC in ROI(tuber+perituber) showed the strongest difference (p = 0.001). Receiver operating characteristic analysis demonstrated that maximum ADC measurements in ROI(tuber+perituber) (area under curve = 0.68 ± 0.05, p < 0.001) had 81% sensitivity and 44% specificity for correctly identifying epileptogenic tubers with a cutoff value of 1.32 μm(2)/ms.
  
  
  CONCLUSIONS
  DTI analysis of tubers and perituberal tissue may help to identify epileptogenic tubers in presurgical patients with TSC more easily and effectively than current invasive methods.
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles. AYogi@mednet.ucla.edu.
authors.forename: Akira
authors.initials: A
authors.lastname: Yogi
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hirata
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Elena
authors.initials: E
authors.lastname: Karavaeva
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Harris
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Joyce Y
authors.initials: JY
authors.lastname: Wu
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Sue L
authors.initials: SL
authors.lastname: Yudovin
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Michael
authors.initials: M
authors.lastname: Linetsky
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Gary W
authors.initials: GW
authors.lastname: Mathern
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Ellingson
authors.affiliation: From the Department of Neuroradiology (A.Y., Y.H., E.K., R.J.H., M.L., B.M.E., N.S.), Department of Pediatrics, Division of Pediatric Neurology (J.Y.W., S.L.Y.), and Department of Neurosurgery (G.W.M.), David Geffen School of Medicine, University of California, Los Angeles.
authors.forename: Noriko
authors.initials: N
authors.lastname: Salamon
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging / Q000379:methods*; D004827:Epilepsy / Q000175:diagnosis* / Q000453:epidemiology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D014402:Tuberous Sclerosis / Q000175:diagnosis* / Q000453:epidemiology / Q000378:metabolism*; D055815:Young Adult