Functional imaging: II. Prediction of epilepsy surgery outcome
Article first published online: 20 JUN 2008
Copyright © 2008 American Neurological Association
Annals of Neurology
Volume 64, Issue 1, pages 35–41, July 2008
How to Cite
Knowlton, R. C., Elgavish, R. A., Bartolucci, A., Ojha, B., Limdi, N., Blount, J., Burneo, J. G., Ver Hoef, L., Paige, L., Faught, E., Kankirawatana, P., Riley, K. and Kuzniecky, R. (2008), Functional imaging: II. Prediction of epilepsy surgery outcome. Ann Neurol., 64: 35–41. doi: 10.1002/ana.21419
- Issue published online: 29 JUL 2008
- Article first published online: 20 JUN 2008
- Manuscript Accepted: 4 APR 2008
- Manuscript Revised: 12 FEB 2008
- Manuscript Received: 3 DEC 2007
- NIH (National Institute of Neurological Diseases and Stroke). Grant Number: K23 NS02218
- Epilepsy Foundation of America (Clinical Training and Research Fellowship)
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).
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.
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).
MSI, FDG-PET, and ictal SPECT each have clinical value in predicting seizure-free surgical outcome in epilepsy surgery candidates who typically require ICEEG. Ann Neurol 2008