Successful epilepsy surgery in frontal lobe epilepsy with startle seizures: a SEEG studyFrontal epilepsy with startle seizures

Abstract

Pre‐surgical assessment and surgical management of frontal epilepsy with normal MRI is often challenging. We present a case of a 33‐year‐old, right‐handed, educated male. During childhood, his seizures presented with mandibular myoclonus and no particular trigger. As a young adult, he developed seizures with a startle component, triggered by unexpected noises. During his ictal episodes, he felt fear and grimaced with sudden head flexion and tonic axial posturing. Similar seizures also occurred without startle. Neuropsychological assessment showed executive dysfunction and verbal memory deficit. The cerebral MRI was normal. Electro‐clinical reasoning, investigations performed, the results obtained and follow‐up are discussed in detail. [Published with video sequence]

Clinical and electrophysiological pattern of startle epilepsy: a comprehensive literature review

“…For Chauvel and colleagues, startle epilepsy seizures thus originate in the motor and premotor cortices. Other recent studies reported a seizure onset zone located in the premotor cortex [21][22], the prefrontal cortex, and anterior and middle cingulate cortex [23]. The SMA was involved in the epileptic network of the majority of cases [21][22][23][24].…”

“…Other recent studies reported a seizure onset zone located in the premotor cortex [21][22], the prefrontal cortex, and anterior and middle cingulate cortex [23]. The SMA was involved in the epileptic network of the majority of cases [21][22][23][24]. Using the Epileptogenicity Maps method, Job et al [18] identified an increase of high frequency oscillations in the premotor and prefrontal areas during startle epilepsy seizures and a constant involvement of the SMA.…”

“…This device produces a background sound that does not disturb hearing but induces a relaxing mood and a feeling of control over the sound environment. Surgery was effective in many studies [7,18,[21][22][23][24]29,30]. However, the proximity to the primary motor cortex requires rigorous preoperative evaluation and the use of intracranial recordings.…”

“…However, the proximity to the primary motor cortex requires rigorous preoperative evaluation and the use of intracranial recordings. Different types of procedures are proposed with similar results: corpus callostomy [7,29], hemispherotomy [30] or focal resection [7,18,[21][22][23][24]. In these studies, postoperative outcomes at one year (or more) were satisfactory with a majority of Engel class 1 [7,18,[21][22][23][24]29,30], and showed no associated motor or cognitive deficit.…”

SEEG re‐exploration in a patient with complex frontal epilepsy with rapid perisylvian propagation and mixed “startle ‐ reflex” seizures

“…Although this is considered predominantly an involuntary response, mainly integrated at the subcortical, reticulo-spinal level, it is now proven that the cortical structures participate in the voluntary response preparation and in the voluntary slow initiation of the response [8]. A few intracranial studies have showed that startle seizures arise from the medial premotor-prefrontal structures such as the SMA, pre-SMA and anterior cingulate cortex [5,9]. Reflex epilepsies, in contrast, are provoked by stimuli that belong to one or several categories (e.g., somatosensory, auditory) [10] which lead, when involving the peri Rolandic cortex, to more focal and long-lasting motor phenomena (e.g., hand contraction).…”