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An epilepsy patient with recurring sensorimotor seizures involving the left hand every 10 min, was imaged with a hyperspectral camera during surgery. By calculating the changes in oxygenated, deoxygenated blood, and total blood volume in the cortex, a focal increase in oxygenated and total blood volume could be observed in the sensory cortex, corresponding to the seizure-onset zone defined by intracranial electroencephalography (EEG) findings. This probably reflects very local seizure activity. After multiple subpial transections in this motor area, clinical seizures abated., (Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.)

Epilepsy that originates outside of the temporal lobe can present some of the most challenging problems for surgical therapy. These epilepsies can be broadly categorized as lesional or non-lesional, with the nonlesional cases being the most difficult to localize. Lesional cases can result from malformations of cortical development, tumors, vascular malformations, or areas of old injury. Some lesions, such as focal cortical dysplasia, can be challenging, in that the boundaries of the pathology can be difficult to define. Presurgical goals include defining the structural lesion, the physiologic abnormality, and normal function in the area. These goals can be achieved using a variety of noninvasive and invasive tests. Surgical techniques vary depending on location and pathology but they always include removal of the epileptic brain tissue while preserving en passage vessels and underlying white matter tracts. Surgical outcomes vary depending on the underlying pathology. Surgeries are usually planned with a goal of no expected postoperative deficits, although temporary deficits may be anticipated in some areas, such as the supplementary motor cortex. Extratemporal epilepsy can be managed well with surgical treatment; but proper patient selection, evaluation, and discussion of expected outcomes and risks are critical in this challenging patient population.

Purpose: Seizure manifesting motor arrest, that is, negative motor seizure (NMS), is a rare epileptic condition in which only inability to conduct voluntary movements or praxis is produced, although consciousness is preserved. The negative motor area (NMA) seems to be responsible, but its generator mechanism has not yet been clarified., Patients and Methods: Three patients manifesting NMS were investigated. Two patients (ages 33 and 17) with intractable frontal lobe epilepsy had subdural grid implantation for epilepsy surgery, and one (age 77) had scalp electroencephalography (EEG) monitoring., Results: Ictal semiologies commonly observed, at least in the two patients, were found as follows; (1) indescribable or ill-localized aura, (2) repetitive involuntary vocalization, (3) inability to speak, (4) inability to move the extremities, and (5) subsequent evolution to positive motor seizures. Awareness and comprehension were preserved throughout the episode before generalized seizures. In two patients with epicortical EEG recording, ictal activity arose from the lateral NMA in one, and from the rostral supplementary motor area in the other. Cortical stimulation at NMA in one patient elicited symptoms identical to NMS. Another patient had scalp EEG and magnetic resonance imaging (MRI) abnormality, both suggesting the epileptogenic focus in the mesial frontal area., Conclusion: We showed that (1) NMS was a rare condition in patients with seizure focus in the frontal lobe, and (2) that the NMA was responsible for the symptoms. The documented state in the present study may reflect ictal apraxia, but it requires further investigation.

Purpose: Medically intractable seizures arising from the sensorimotor (rolandic) cortex present a formidable challenge for epileptologists and epilepsy surgeons. The objective of this study was to evaluate the safety and efficacy of surgical treatment for seizures in this region., Methods: We retrospectively reviewed the medical records of 24 children and adolescents who underwent surgical management of refractory rolandic epilepsy at our institution., Results: Patient age at the time of surgery ranged between 1.9 and 19.2 years, and median postoperative follow-up was 2.3 years. Three patients had clear lesions on preoperative magnetic resonance imaging (MRI) that correlated with noninvasive electroencephalography (EEG) and underwent single-stage lesionectomies. Of the 21 patients who underwent invasive monitoring, 19 underwent therapeutic procedures, including lesionectomy, topectomy, and multiple subpial transections. Engel class I and II outcomes were seen in five of six patients (84.0%) after lesionectomy and in seven of nine patients (77.0%) and four of six patients (66.7%) after sensorimotor corticectomy or multiple subpial transections (MSTs), respectively. At last follow-up, neurologic deficits were observed following 50.0% (n = 3 of 6) of lesionectomies and 67.0% (n = 7 of 9) of topectomies; no neurologic deficits were seen in patients undergoing motor cortex MSTs. No correlation existed between seizure outcome and duration of epilepsy, age at diagnosis, age at surgery, histopathology, or the presence or absence of a discrete lesion., Discussion: Surgery for appropriately selected children with intractable seizures arising from rolandic cortex was effective and associated with minimal neurologic morbidity in many cases. Engel I-II outcome was achieved in 77% of patients overall, and neurologic deficits were often mild and improved over time. Lesionectomy resulted in the best seizure control, followed by topectomy, and then MSTs.

Purpose: Lateralized clonic jerks of the extremities during epileptic seizures usually arise from the contralateral rolandic cortex. In our exceptional case one-sided extremity twitches related to epileptiform activity in the ipsilateral frontal lobe., Methods: Case study with clinical-electroencephalographic correlation., Results: A 47-year-old man suffered destruction of most of his right cerebral hemisphere, including the perirolandic region. Epilepsia partialis continua (EPC) ensued, with clonic jerks of the proximal right upper and lower limbs temporally related to periodic lateralized epileptiform discharges (PLEDs) from the parasagittal region of the right frontal lobe with a variable time interval over 100 ms. Sectioning of the subcortical callosal and projection connections of the frontal lobe abolished the clonic jerks., Conclusions: We propose the ipsilateral EPC arose from projections from the supplementary motor region to the medullary reticular formation to account for the long and variable latency between PLEDs and jerks.

Purpose: To analyze the role of selective middle cerebral artery (MCA) Wada tests in the presurgical workup of patients with drug-resistant focal epilepsies., Methods: Twenty MCA Wada test procedures were performed to identify eloquent cortex (a) in nine patients with hemispheric lesions involving the motor cortex (connatal MCA infarct, n = 5; unilateral cortical dysplasia, n = 3; Rasmussen encephalitis, n = 1), (b) five patients with circumscribed neoplastic or nonneoplastic lesions adjacent to the motor cortex or classic language areas, and (c) for purely electrophysiologic reasons, in two patients with electrical status epilepticus in sleep (ESES). Sodium amobarbital and [99mTc]-HMPAO were simultaneously injected via a microcatheter into the distal M1 segment (n = 7), the inferior MCA trunk (n = 3), or into MCA branches (n = 10)., Results: Co-registered single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI;n = 18) showed that sodium amobarbital did not reach the target area in three procedures. Temporary neurologic deficits occurred in 12 procedures. Eleven patients were operated on with the following surgical approaches: functional hemispherectomy, n = 3; partial or extended lesionectomy, n = 4; anterior temporal lobectomy, n = 1; and multiple subpial transsections, n = 3. Seizure freedom (Engel class I) was achieved in five patients., Conclusions: Selective MCA Wada tests can contribute to risk assessment concerning postsurgical motor deficits before functional hemispherectomy. Other indications are less clear: The identification of language areas is targeted primarily by electrical-stimulation mapping after subdural grid implantations, and selective MCA Wada tests in ESES patients yet have to be validated in larger patient groups.

We studied long-term outcome (range, 28-89 months; mean, 56 months) after multiple subpial transections (MSTs) for medically refractory epilepsy. Forty-three (79.6%) of 54 patients had a consistent significant reduction in seizure frequency, and 27 (50%) of the 54 were either entirely seizure free or virtually so. However, 10 (18.6%) patients sustained an increase in seizure frequency several years after surgery, after showing initial postoperative improvement. This suggests that late seizure recurrence is a more important problem in cases in which MST has been performed than for pure resections.

Purpose: To study the efficacy of extensive coverage of the brain surface with subdural grids in defining extratemporal cortical areas amenable for resection in patients with refractory extratemporal epilepy (R-ExTE) and normal or nonlocalizing magnetic resonance imaging (MRI) scans., Methods: Sixteen patients with R-ExTE were studied. Eleven patients had simple partial, eight had complex partial, and three had supplementary motor area seizures. Seizure frequency ranged from three per month to daily episodes. Interictal EEG showed large focal spiking areas in 11 patients, secondary bilateral synchrony in four, and was normal in one patient. Surface ictal recordings were nonlocalizing in six patients, and in 10, they disclosed large ictal focal spiking areas. MRI was normal in 10 patients, and in six patients, focal nonlocalizing potentially epileptogenic lesions were found. All patients were given an extensive coverage of the cortical convexity with subdural electrodes through large unilateral (n = 13) or bilateral (n = 3) craniotomies. Bipolar cortical stimulation was carried out through the implanted electrodes., Results: Interictal invasive recording findings showed widespread spiking areas in 13 patients and secondary bilateral synchrony in three. Ictal invasive recordings showed focal seizure onset in all patients. There were six frontal, two parietal, one temporooccipital, four rolandic, and three posterior quadrant resections. Thirteen patients had been rendered seizure free after surgery, and three had > or =90% of seizure-frequency reduction. Pathologic findings included gliosis (n = 10), cortical dysplasia (n = 5), or no abnormalities (n = 1). Six patients had transient postoperative neurologic morbidity., Conclusions: Extensive subdural electrodes coverage seems to be an effective way to investigate patients with R-ExTE and normal or nonlocalizing MRI findings.

Purpose: Although resection of an epileptogenic region is the mainstay of epilepsy surgery, epileptogenic areas in functionally critical cortex cannot be approached in that manner. Multiple subpial transection (MST) was developed to treat those refractory seizures without causing unacceptable neurologic deficit. We review our experience with this technique., Methods: Twelve patients who underwent MST with or without resection between 1990 and 1998 were retrospectively reviewed with regard to seizure and neurologic outcome, and predictive factors., Results: Five (42%) of 12 patients obtained a significant improvement in seizure frequency, and two other patients had a marked decrease in the severity of their seizures. Resection with MST reduced seizure frequency more, but this was not a significant difference. No predictive factors for outcome were identified. Only one patient sustained any persistent neurologic deficit., Conclusions: In selected patients, MST may be a viable alternative when the epileptogenic focus lies in unresectable cortex. A multicenter study with appreciable patient numbers will be necessary to define predictive factors for success.

Purpose: To evaluate the suspected epileptic origin in children with episodes masquerading as sleep terrors., Method: One such child was investigated with scalp-derived long-term monitoring (LTM), inter and ictal single photon emission computed tomography (SPECT) scans, and an invasive LTM, followed by surgical subpial slicing of the focally discharging motor cortex., Results: The scalp-derived LTM and the SPECT scans did not localize the suspected epileptogenic focus. The invasive LTM revealed the focal onset of the ictal discharge. After the surgery, the seizures have been 90% controlled. No deficits resulted from the surgery., Conclusions: Although most nocturnal terrors (NTs) are parasomnias, in a few children their frequent episodes that masquerade as NTs have an epileptic origin. There are several features to distinguish these from common NTs or from other frontal lobe epilepsies.

Purpose: To study the effectiveness of surgical therapy on 2 patients with startle epilepsy with infantile brain damage (SEIBD), a rare but distinctive epileptic syndrome characterized by motor seizures resistant to antiepileptic drugs (AEDs)., Methods: The patients with SEIBD both had hemiplegia, due to gross contralateral hemispheric lesions, and suffered from tonic postural seizures, frequently provoked by sudden unexpected somatosensory stimuli on the paretic side of the body. These attacks occasionally caused the patients to drop to the floor, and mild-to-moderate injuries had been sustained; they were resistant to all currently available AEDs. Consequently, these daily drop attacks severely restricted the patients' social lives and school participation. Both patients underwent corpus callosotomy and resection of epileptogenic premotor and supplementary motor lesions. One patient also underwent additional multiple subpial transections of the primary sensorimotor area., Results: Seizures, as well as quality of life, improved dramatically in both patients after surgery., Conclusions: Startle epilepsy with infantile hemiplegia is a distinct epileptic syndrome characterized by structural brain damage restricted primarily to one hemisphere, large ipsilateral epileptogenic lesions involving the perisensorimotor area, refractory startle-provoked drop attacks, and a good response to epilepsy surgery.

The mesiofrontal cortex comprises a number of distinct anatomic and functional areas. Structural lesions and cortical dysgenesis are recognized causes of mesial frontal epilepsy, but a specific gene defect may also be important, as seen in some forms of familial frontal lobe epilepsy. The predominant seizure manifestations, which are not necessarily strictly correlated with a specific ictal onset zone, are absence, hypermotor, and postural tonic seizures. Other seizure types also occur. The task of localization of the epileptogenic zone can be challenging, whether EEG or imaging methods are used. Successful localization can lead to a rewarding outcome after epilepsy surgery, particularly in those with an imaged lesion.

Our purpose was to evaluate the safety and efficacy of surgical treatment for perirolandic lesional epilepsy. We analyzed the records of 14 consecutive patients who underwent a stereotactic lesionectomy for intractable partial epilepsy between 1985 and 1994. All patients had a neuroimaging-identified lesion in the perirolandic cortex. The mean duration of follow-up was 6 years (range 1-11 years). Thirteen patients (93%) had a significant improvement in seizure tendency. Eleven patients (78%) were rendered seizure-free. Morbidity occurred in only one patient, who experienced an increased monoparesis after surgery. Stereotactic lesionectomy is an effective surgical strategy in patients with perirolandic lesional epilepsy. The recent development of functional brain imaging using subtraction ictal single-photon emission computed tomography co-registered with volumetric magnetic resonance imaging has been shown to be a reliable indicator of epileptic brain tissue that may significantly alter the preoperative evaluation in patients with extratemporal seizures.

On the basis of cytoarchitectural and functional studies, the frontal lobe can be subdivided into the primary motor cortex, premotor cortex, prefrontal cortex, and the limbic and paralimbic cortices. However, we are still a long way from clearly identifying individual frontal lobe epilepsies. Instead, we are limited to a discussion of frontal lobe seizures arising from various regions of the frontal lobe. Supplementary motor area epilepsy and perirolandic epilepsy have been quite well defined, in contrast to syndromes involving other regions of the frontal lobe. Recent technological advances in neuroimaging, electroencephalography, magnetoencephalography and detailed videotape analysis of seizure semiology may enable us to delineate these frontal lobe syndromes with better accuracy, thereby improving outcome after epilepsy surgery.