Functional imaging: II. Prediction of epilepsy surgery outcome

Ann Neurol. 2008 Jul;64(1):35-41. doi: 10.1002/ana.21419.


Objective: To gain information on the value of magnetic source imaging (MSI), 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET), and ictal single photon emission computed tomography (SPECT) to predict seizure-free outcome following epilepsy surgery in patients who require intracranial electroencephalography (ICEEG).

Methods: This work was part of a prospective observation study of epilepsy surgery candidates not sufficiently localized with scalp EEG and MRI. Of 160 patients enrolled 62 completed ICEEG and subsequent surgical resection. Sixty-one percent resulted in an Engel I seizure-free outcome at a minimum of one-year follow-up (mean = 3.4 years). Sensitivity, specificity, and predictive values were computed for each modality. Multivariate logistical regression was used to identify prediction of surgical outcome by imaging test.

Results: MSI sensitivity for a conclusively localized study was 55% with a positive predictive value of 78%. Eliminating non-diagnostic MSI cases (no spikes captured during recording) yielded a corrected negative predictive value of 64%. With available comparison subgroups FDG-PET and ictal SPECT values were similar to MSI. The OR (adjusted for epilepsy and MRI classification) for MSI prediction of seizure-free outcome was 4.4 (p =0.01). In cases with both PET and MSI, the adjusted OR for PET was 7.1 (p <0.01) and for MSI was 6.4 (p = 0.01). In the cases with all three tests (n = 27), ictal SPECT had the highest OR of 9.1 (p = 0.05).

Interpretation: MSI, FDG-PET, and ictal SPECT each have clinical value in predicting seizure-free surgical outcome in epilepsy surgery candidates who typically require ICEEG.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Brain / diagnostic imaging
  • Brain / physiopathology
  • Brain / surgery
  • Child
  • Child, Preschool
  • Cohort Studies
  • Decision Support Techniques
  • Electroencephalography / methods
  • Electroencephalography / standards
  • Epilepsy / diagnostic imaging*
  • Epilepsy / physiopathology
  • Epilepsy / surgery*
  • Female
  • Fluorodeoxyglucose F18
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Patient Selection
  • Positron-Emission Tomography / methods*
  • Positron-Emission Tomography / standards
  • Predictive Value of Tests
  • Preoperative Care / methods*
  • Preoperative Care / standards
  • Prospective Studies
  • Tomography, Emission-Computed, Single-Photon / methods*
  • Tomography, Emission-Computed, Single-Photon / standards
  • Treatment Outcome


  • Fluorodeoxyglucose F18