Insular cortex epilepsy: an overview.

In this review the authors discuss insular cortex epilepsy, an under-recognized localization-related syndrome that may explain some temporal (but also frontal and parietal lobe) epilepsy surgery failures. The insula may generate a variety of symptoms (including visceral, motor and somatosensory) that mimic temporal, frontal or parietal lobe onset seizures. Intracerebral electrodes directly implanted in the insula are currently the only way to confirm insular seizures. Consideration should be given to exploration of the insular cortex in MRI negative patients with seizure semiology consistent with insular onset seizures. Electroencephalographers should have a low threshold to sample this region, especially in the absence of a structural lesion. Microneurosurgical technical advances allow resective surgery of the insula with relatively low morbidity.