Temporal lobe syncope: clinical variants

Temporal lobe syncope (TLS) is a term coined by Landolt. Characteristically, the patient has psychomotor and drop attacks, and the interictal electroencephalogram (EEG) shows temporal lobe epileptic abnormalities. TLS is synonymous with type III complex partial seizures (CPSs) in the Delgado Escueta classification. Several variants of TLS can be recognized including atonic akinetic, simple akinetic, atonic, atonic-tonic complex (automatisms), sexual seizures, stress-induced convulsions, and gelastic atonic seizures. TLS must be distinguished from drop attacks of vertebrobasilar insufficiency and associated EEG abnormalities, and from hereditary tachyarrhythmias mimicking stress-induced convulsions. Epileptic falls and drop attacks are discarded by ictal EEG recordings. Recognition of TLS variants is important in the prospective evaluation of the surgical treatment of epilepsy given the past conflicting reports on the differential outcome of surgically treated CPSs. TLS is an attractive clinical term, easy to remember, and with pathophysiologic relevance to the clinician confronting the patient with a history of syncope and whose EEG discloses temporal lobe paroxysmal activity. The detailed ictal electrophysiology of TLS is unknown.     

Complex partial seizures of frontal lobe origin

Complex partial seizures of medial or orbital frontal origin were documented in 10 of 90 patients with intractable epilepsy who were studied with depth electrodes. The clinical features that, in part, served to distinguish these seizures from complex partial seizures originating elsewhere included brief, frequent attacks, complex motor automatisms with kicking and thrashing, sexual automatisms, vocalization, and frequent development of complex partial status epilepticus. The constellation of clinical characteristics was often bizarre, leading to the erroneous diagnosis of hysteria. Stereotyped attack patterns helped establish the diagnosis of epilepsy. Interictal and ictal scalp electroencephalograms were often not helpful and were sometimes misleading.     

Occipital lobe epilepsy: clinical characteristics, seizure spread patterns, and results of surgery.

Twenty-five patients with occipital lobe seizure origin were retrospectively evaluated to determine clinical seizure characteristics and electroencephalographic manifestations. Certain symptoms and signs served to identify occipital lobe origin in 22 (88%). These included elementary visual hallucinations, ictal amaurosis, eye movement sensations, early forced blinking or eyelid flutter, and visual field deficits. Eye or head deviation, or both, was observed frequently and was contralateral to the side of seizure origin in 13, but 3 patients exhibited ipsilateral deviation in some or all their seizures. After the initial signs and symptoms, clinical seizure characteristics resembled those of seizures originating elsewhere. Seizures typical of temporal lobe origin with loss of contact and various types of automatic, semipurposeful activity occurred in 11 patients. Seizures in 3 patients exhibited asymmetrical tonic or focal clonic motor patterns characteristic of frontal lobe seizures. Eleven of the 25 patients had, on two occasions, two or more distinctly different seizure types. Scalp electroencephalographic findings were seldom helpful for occipital lobe localization and were frequently misleading. Intracranial electroencephalographic recording correctly identified occipital lobe seizure origin in most, but not all, patients who had such studies. Intracranial electroencephalic recording also proved the variability in clinical seizure characteristics was related to different seizure spread patterns, medially or laterally above and below the sylvian fissure, both ipsilateral and contralateral to the occipital lobe of seizure origin. Eighteen patients had occipital lobe lesions detected with computed tomographic or magnetic resonance imaging scans or both. Resection of the lesions in 16 patients produced excellent results in 14 (88%). Five patients had temporal lobectomies, with good results in 3, but poor results in 2. Two patients with unlocalized seizures had complete section of the corpus callosum, 1 with a good result and the other with a poor result.     

Lateralizing value of postictal automatisms in temporal lobe epilepsy

PURPOSE: To describe clinical characteristics and lateralizing value of postictal automatisms in patients with temporal lobe epilepsy (TLE). METHODS: One hundred and ninety-three videotaped seizures of 55 consecutive patients with refractory TLE and postoperatively seizure-free outcome were analyzed. Ictal as well as postictal (manual, oral and speech) automatisms were monitored. RESULTS: Thirty-four (62%) of the 55 patients showed PA at least once during their seizures. Postictal automatism was observed in 70 (36%) attacks as manual (21%), oral (13%) or speech (9%) automatisms. Fifteen seizures contained a combination of two different postictal automatisms. The presence of postictal oral automatisms did not lateralize the seizure onset zone (p=0.834). Speech automatisms (repetitive verbal behavior) occurred more frequently after left-sided seizures (p=0.002). Postictal unilateral manual automatism showed no lateralizing value occurring by the ipsilateral hand in 10 and the contralateral upper limb in 6 seizures (p=0.454). CONCLUSION: : Postictal automatism is a relatively frequent phenomenon in TLE. Postictal speech automatism lateralizes the seizure onset zone to the left hemisphere. Our observation can help the presurgical evaluation of TLE because verbal perseveration frequently occurs spontaneously, even in seizures without appropriate postictal language testing.     

Predictive clinical factors for the differential diagnosis of childhood extratemporal seizures

PURPOSE: To describe predictive clinical factors for the differentiation between childhood frontal lobe epilepsy (FLE) and posterior cortex epilepsy (PCE). METHODS: Two independent, blinded investigators analyzed 177 seizures from 35 children (aged 11 months to 12 years) with extratemporal epilepsy selected by postoperative seizure-free outcome. Semiologic seizure components and different periictal signs were observed. Age at onset, auras, seizure frequency, and nocturnal dominance, as well as surgical and histopathologic data, were collected from medical charts. RESULTS: Twenty patients had FLE, and 15 had PCE. Patients from both groups had daily seizures without significant differences in frequency but with higher nocturnal dominance in children with FLE (p < 0.05). Visual aura, nystagmus, and versive seizure were observed exclusively in the PCE group, whereas somatosensory aura and hypermotor seizures appeared only in FLE. Tonic seizures were significantly more frequent in FLE (p < 0.01), whereas the presence of clonic seizure (FLE; p = 0.07) and postictal nose-wiping (PCE; p = 0.05) showed only a trend to localize the seizure-onset zone. Myoclonic seizures, epileptic spasms, psychomotor seizures, atonic seizures, oral and manual automatisms, as well as vocalization and eye deviation appeared in both groups without significant differences in their frequency. CONCLUSIONS: Characteristic features described in adults' extratemporal epilepsies were frequently missing during childhood seizures, especially in infants and preschool children. Ictal features help only a little in differentiating childhood FLE from PCE. Nocturnal appearance and the type of aura have high localizing value; therefore an accurate history taking is still an essential element of pediatric presurgical evaluation.     

Intractable seizures of frontal lobe origin: clinical characteristics, localizing signs, and results of surgery

PURPOSE: We analyzed the clinical characteristics of seizures of frontal lobe (FL) origin with particular emphasis on establishing different categories and determining if these categories had any localizing or lateralizing value. In addition, results of surgery are reported. METHODS: Seizure characteristics were established by historical review and electroencephalographic/videotape analysis of 449 seizures in 26 adult patients with refractory seizures of FL origin. RESULTS: No outstanding risk factor was identified for seizures of FL origin. Seizures were frequent (7.1 per week), brief (mean duration, 48.3 seconds), and had a nocturnal preponderance in 58% of the patients. Status epilepticus was reported in 54%, and generalized convulsions as a prominent seizure type were reported in 26% of patients. The most common reported aura was a nonspecific sensation, often localized to the head (35%). Early forced head and eye deviation was not a consistent lateralizing sign, whereas late head and eye deviation always occurred contralateral to the site of seizure origin. Early asymmetric tonic posturing occurred consistently contralateral to the side of seizure origin. Clinical seizure patterns did not consistently localize to specific regions of the frontal lobe, although there were some noticeable trends: focal clonic seizures were associated with seizure origin in the frontal convexity; tonic seizures were most often associated with origin in the supplementary motor area but also occurred with origin in other parts of the frontal lobe; seizures resembling typical temporal lobe seizures with oroalimentary automatisms were observed with seizure origin in the orbitofrontal region; and seizures with hyperactive, frenetic automatisms were not associated with any specific region within the frontal lobes. Eighty percent of patients had favorable seizure outcome after surgery (class I/II). CONCLUSION: Although certain clinical features are characteristic for seizures of frontal lobe origin and some have lateralizing value, they do not localize to specific areas within the FL. After careful presurgical evaluation, both lesional and nonlesional patients benefit from epilepsy surgery.     

Somatomotor manifestations in temporal lobe seizures

Some authors include somatomotor manifestations (SMM) among the clinical features of temporal lobe seizures in man; however, data are limited and conflicting. This study describes 101 seizures recorded during stereo-EEG explorations in 50 patients, selected on the basis of the demonstration of onset in temporal lobe structures (stereo-EEG) and the presence of lateralized SMM and/or secondary generalization (SG). SMM and SG were present in about 20% of our population of patients with temporal seizures explored with stereo-EEG, and were only rarely observed during the first 10 s (early SMM) of the seizures (less than 10%). Seizures characterized by early SMM were generally induced by electrical stimulation or chemical activation and only exceptionally spontaneous. In all cases the ictal electrical discharge also involved at an early stage extratemporal structures such as the rolandic operculum, the parietal lobe, or contralateral temporal structures. In most cases (greater than 90%) SMM represented a late (greater than 10 s) event in the ictal symptomatology. The face and the upper limb were by far the most frequently involved segments. Thirty-eight percent of seizures ended up in SG. The associated ictal symptomatology was rather poor and differed from our previous findings in temporal lobe seizures: oroalimentary automatisms were relatively rare, whereas an impairment of consciousness was observed in more than 50% of seizures. The critical electrical discharge had a long duration and always involved extratemporal structures in one or both hemispheres. The involvement of the central region could be demonstrated in all patients with deep electrodes in that region. In conclusion, SMM are not characteristic of temporal lobe seizures, and their presence indicates spreading of the critical discharge beyond the temporal lobe.     

Frontal Lobe Seizures: Electroclinical Syndromes

Summary: To define further the electroclinical manifestations of frontal lobe epilepsy (FLE), we studied 150 seizures manifested by 24 patients; 18 patients had subdural electrode arrays (SEA). The findings in these patients clearly overlapped presumably reflecting the interconnections between functionally related frontal zones; yet the manner in which the symptoms clustered and the sequence in which they occurred generally indicated the anatomic site of the epileptogenic zone. We divided the patients into three major groups: (a) those with supplementary motor seizures, (b) those with focal motor seizures, and (c) those with complex partial seizures (CPS, psychomotor seizures). Supplementary motor seizures began with tonic posturing of the extremities. Focal motor seizures generally began with conscious contralateral version or unilateral clonic focal motor activity; tonic posturing was noted only late in the seizure. CPS (psychomotor) began with unresponsiveness at onset, followed by staring or unconscious contraversion. We compared frontal lobe seizures with temporal lobe seizures reported previously; oral-alimentary automatisms, repetitive hand movements, or looking around, were more common in temporal lobe seizures, whereas tonic posturing and bicycling movements were more common in frontal lobe psychomotor seizures.     

Nonmanipulative proximal upper extremity automatisms lateralize contralaterally in temporal lobe epilepsy

Purpose : Upper extremity automatisms are considered to be an ipsilateral seizure lateralizing sign in temporal lobe epilepsy (TLE). Herein we describe different types of contralateral upper extremity automatisms (CUEAs). Methods : One hundred ninety‐three video–(electroencephalography) EEG recordings of 59 patients were reviewed. Other than two patients who refused surgery, all patients underwent standardized temporal lobectomy with favorable postoperative outcome. Fifty‐seven seizures of 21 patients were selected with CUEAs. We evaluated their electroclinical characteristics and their relation to other lateralizing motor symptoms. Results : Two types of CUEAs were observed. Nonmanipulative, proximal upper extremity automatisms were seen unilaterally and contralaterally to the operated side. These automatisms were rhythmic; repetitive; and often occurred with a circulatory component resembling waving, flaunting, circling, or stirring movements. They occurred in 29 seizures (15%) of 11 patients (19%), in most seizures in the first half of the seizure, and never postictally, in various time sequences and combined with dystonic/tonic posturing or limb immobility. Manipulative/distal type of CUEAs occurred in 11 seizures (6%) of 7 patients (12%) on the unexpected contralateral side. These CUEAs were seen in all phases of the seizures, including in the postictal state. Discussion : Nonmanipulative unilateral proximal upper extremity automatism is a reliable lateralizing sign to the contralateral hemisphere in TLE. This sign may be pathophysiologically related to dystonic/tonic posturing. Manipulative distal automatisms have less lateralizing value.     

额叶癫痫的特点及手术治疗

目的 :分析额叶癫痫的临床特征、发作期及发作间期脑电图特点 ,探讨额叶癫痫手术治疗。方法 :应用视频脑电图对 9例额叶癫痫患者进行长程监测 ,并对其中 6例记录颅内脑电图。分析癫痫发作的临床表现及脑电图特点 ,定位致痫灶 ,行手术切除。结果 :额叶癫痫的发作特点为 :发作频繁而短暂 ,以睡眠期发作为主 ,常见过度运动 ,姿势性强直 ,发声等发作症状。发作期可见棘波节律 ,广泛低幅快活动 ,节律性慢波等特征性脑电活动。颅内电极记录可清晰显示异常脑电活动的发作起源及扩散情况 ,有助于定位致痫灶。手术切除病灶及致痫灶 ,效果满意。结论 :额叶癫痫是一组具有特征性的癫痫综合征 ,颅内电极记录有助于揭示其脑电活动变化。对于难治疗性额叶癫痫 ,准确定位致痫灶是手术成功的关键。