title: Comparison of brain perfusion SPECT parameters accuracy for seizure localization in extratemporal lobe epilepsy with discordant pre-surgical data.
abstract: OBJECTIVE
  Extratemporal lobe epilepsy is difficult to localize. We aimed to define the best parameter(s) of SPECT for confirmation of seizure origin among the region of maximum cerebral perfusion in ictal phase (MP), maximum change of cerebral perfusion from interictal to ictal phase (MC), and maximum extent of hyperperfusion in ictal phase (ME) of (99m)Tc ECD brain perfusion SPECT as well as combined SPECT parameters, and combined SPECT and MRI for seizure localization in extratemporal lobe epilepsy.
  
  
  METHODS
  Twenty intractable extratemporal lobe epilepsy patients who had (99m)Tc-ECD brain SPECT were reviewed. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of single SPECT parameter, combined SPECT parameters, and combined SPECT and MRI parameters for localization of seizure origin were calculated using pathology and surgical outcomes (Engel class I and II) as gold standards.
  
  
  RESULTS
  Combined SPECT parameters provided more specificity, PPV and accuracy than single SPECT parameters. The best combined SPECT parameters was MP+MC with 80.6 % accuracy, 92.4 % specificity and 43.8 % PPV. Combination of SPECT parameter with MRI (ME+MRI) was the most sensitive (41.7 %), specific (97.5 %), accurate (88.2 %) parameter and had highest PPV (76.9 %) and NPV (89.3 %) for seizure localization. It improved specificity and PPV when compared to MRI alone.
  
  
  CONCLUSIONS
  Combined SPECT parameters improved the specificity and accuracy in seizure localization. The most specific and accurate SPECT combination is MP+MC. The combined SPECT parameter with MRI further improved sensitivity, specificity, accuracy, PPV and NPV. The authors recommend using SPECT combination, MP+MC, when MRI is negative and ME+MRI when there is MRI lesion.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Chulalongkorn University, Rama 4 Road, Pathumwan, Bangkok, 10330, Thailand, supatporn@hotmail.com.
authors.forename: Supatporn
authors.initials: S
authors.lastname: Tepmongkol
authors.forename: Kanokporn
authors.initials: K
authors.lastname: Tangtrairattanakul
authors.forename: Sukalaya
authors.initials: S
authors.lastname: Lerdlum
authors.forename: Tayard
authors.initials: T
authors.lastname: Desudchit
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D003545:Cysteine / Q000031:analogs & derivatives; D004828:Epilepsies, Partial / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D064847:Multimodal Imaging / Q000379:methods; D015609:Organotechnetium Compounds; D057234:Preoperative Period; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012640:Seizures / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine