Eating epilepsy: phenotype, MRI, SPECT and video-EEG observations

Background: Eating epilepsy is one of the rare forms of reflex epilepsy precipitated by eating. Previous studies have demonstrated lesions due to variable aetiology involving the temporolimbic and suprasylvian regions.

Objective: To study anatomical correlates of reflex eating epilepsy using multimodality investigations (MR imaging, video-EEG and SPECT).

Methodology: Six patients (M:F=3:3; mean age: 20.7±4.9 years) with eating epilepsy were subjected to MRI of brain, video-EEG studies and SPECT scan. These were correlated with phenotypic presentations.

Results: Among the five patients with ictal recording of eating epilepsy during video-EEG, semiology was characterized by behavioural arrest followed by either flexion or extension of trunk and neck and two patients had speech arrest and four had salivation from angle of mouth. Another patient had EEG changes during "thought about eating". Four patients had perisylvian frontal lobe lesions and one had high frontal lesion on MRI. Ictal EEG (n=6) showed ictal rhythmic slowing/fast activity in parieto-temporal (n=2) or fronto-temporal (n=4) regions with subsequent secondary generalization in three. Ictal and interictal SPECT imaging showed changes in frontal lobe (n=1), anterior temporal lobe (n=1), and parieto-insular region (n=1) suggesting it to be seizure onset zone. Three of four patients with structural lesions in MRI had concordant ictal EEG and ictal SPECT changes.

Conclusion: Lesions near the perisylvian region might play a major role in eating epilepsy.