M. Lemesle et al., Correlation between inter-ictal regional cerebral blood flow and sphenoidal electrodes - recorded inter-ictal spikes in mesial temporal lobe epilepsy, NEUROL RES, 22(7), 2000, pp. 674-678
The objective of this study was to assess the reliability of the diagnosis
of mesial temporal lobe epilepsy using EEG and sphenoidal electrodes. Inter
-ictal 99 m Tc-HMPAO SPECT scans were registered in 21 patients with confir
med mesial temporal lobe epilepsy identified by scalp EEG and sphenoidal el
ectrodes. Visual and quantitative SPECT analysis was performed blind to EEG
data. An asymmetry index (Al) was measured from the ratio of two symmetric
al regions of interest A temporal lobe hypoperfusion was defined as an upta
ke reduced by 5% with respect to the contralateral region. Inter-ictal SPEC
T abnormalities were observed in 12 out of 21 patients (57%) from both visu
al and quantitative analysis (focal hypoperfusion in 11 cases, focal hyperp
erfusion in one case). In seven patients (33%) both visual and quantitative
scintigraphy were normal. Abnormal Al was found in 11/15 patients with a h
igh frequency of seizures and in 1/6 patients with a low frequency of seizu
res. The major data is that the probability to have an abnormal SPECT is st
atistically correlated to the frequency of the epileptic fits. The couple E
EG recordings with sphenoidal electrodes and SPECT is sensitive and reliabl
e in the diagnosis of mesial temporal lobe epilepsy.