Comparative analysis of MR imaging, ictal SPECT and EEG in temporal lobe epilepsy: a prospective IAEA multi-center study.
OBJECTIVE
MR imaging, ictal single-photon emission CT (SPECT) and ictal EEG play important roles in the presurgical localization of epileptic foci. This multi-center study was established to investigate whether the complementary role of perfusion SPECT, MRI and EEG for presurgical localization of temporal lobe epilepsy could be confirmed in a prospective setting involving centers from India, Thailand, Italy and Argentina.


METHODS
We studied 74 patients who underwent interictal and ictal EEG, interictal and ictal SPECT and MRI before surgery of the temporal lobe. In all but three patients, histology was reported. The clinical outcome was assessed using Engel's classification. Sensitivity values of all imaging modalities were calculated, and the add-on value of SPECT was assessed.


RESULTS
Outcome (Engel's classification) in 74 patients was class I, 89%; class II, 7%; class III, 3%; and IV, 1%. Regarding the localization of seizure origin, sensitivity was 84% for ictal SPECT, 70% for ictal EEG, 86% for MRI, 55% for interictal SPECT and 40% for interictal EEG. Add-on value of ictal SPECT was shown by its ability to correctly localize 17/22 (77%) of the seizure foci missed by ictal EEG and 8/10 (80%) of the seizure foci not detected by MRI.


CONCLUSIONS
This prospective multi-center trial, involving centers from different parts of the world, confirms that ictal perfusion SPECT is an effective diagnostic modality for correctly identifying seizure origin in temporal lobe epilepsy, providing complementary information to ictal EEG and MRI.
Zaknun
John J
JJ
Department of Nuclear Medicine, University Hospital of Innsbruck, Innsbruck, Austria. J.Zaknun@iaea.org
Bal
Chandrasekhar
C
Maes
Alex
A
Tepmongkol
Supatporn
S
Vazquez
Silvia
S
Dupont
Patrick
P
Dondi
Maurizio
M
D000293:Adolescent; D000328:Adult; D001118:Argentina; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007194:India; D007390:International Agencies; D007558:Italy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013785:Thailand; D015899:Tomography, Emission-Computed, Single-Photon