Postictal nose-rubbing in the diagnosis, lateralization, and localization of seizures

BACKGROUND

Semiology is very useful in the diagnosis and classification of seizures. Some clinical signs occur primarily with specific localization-related epilepsies.

OBJECTIVE

To evaluate postictal nose-rubbing as a potential diagnostic sign and a potential lateralizing or localizing indicator.

METHODS

We reviewed presurgical prolonged video-EEG results of 50 consecutive patients with right temporal lobe epilepsy (TLE), 50 consecutive patients with left TLE, 50 consecutive patients with frontal lobe epilepsy, 11 consecutive patients with generalized epilepsy, and 100 consecutive patients with nonepileptic events. Videotapes of all events were reviewed independently by two investigators who were blinded to the results of the monitoring. The episodes of nose-rubbing and the hand with which the patient rubbed the nose were recorded.

RESULTS

Nose-rubbing occurred in 25 of 50 (50%) right TLE patients and in 21 of 50 (42%) left TLE patients. Approximately 90% of patients rubbed his or her nose with the ipsilateral hand. Nose-rubbing occurred in 5 of 50 (10%) frontal lobe epilepsy patients. Nose-rubbing was not seen in any patient with generalized epilepsy or nonepileptic events. Postictal nose-rubbing did not occur after secondarily generalized seizures.

CONCLUSIONS

Nose-rubbing is an easily observed phenomenon, has high interobserver reliability, and provides useful lateralizing information in patients with TLE. It was less frequently seen in extratemporal lobe epilepsy and was not seen after generalized seizures or nonepileptic events.

Oxcarbazepine: double-blind, randomized, placebo-control, monotherapy trial for partial seizures

OBJECTIVE

To evaluate the efficacy and safety of oxcarbazepine in a placebo-control trial.

METHODS

A multicenter, double-blind, randomized, placebo-control, two-arm parallel group, monotherapy design was used to compare oxcarbazepine administered 1,200 mg twice daily to placebo in hospitalized patients with refractory partial seizures, including simple and complex partial seizures and partial seizures evolving to secondarily generalized seizures. Patients exited the trial after completing the 10-day double-blind treatment phase or after experiencing four partial seizures, two new-onset secondarily generalized seizures, serial seizures, or status epilepticus, whichever came first.

RESULTS

Analysis of the primary efficacy variable--time to meeting one of the exit criteria--showed a statistically significant effect in favor of oxcarbazepine (p = 0.0001). The secondary efficacy variables--percentage of patients who met one of the exit criteria (p = 0.0001) and total partial seizure frequency per 9 days during the double-blind treatment (p = 0.0001)--were also statistically significant in favor of oxcarbazepine.

CONCLUSION

These results demonstrate that oxcarbazepine given as monotherapy is effective and safe for the treatment of partial seizures in this paradigm.

Ambulatory EEG monitoring

Advances in computer technology offer increased capabilities for ambulatory EEG monitoring. The technical specifications of currently available ambulatory EEG machines reasonably approximate inpatient EEG equipment. However, the evolution of ambulatory EEG from 3-channel analog cassette recordings to reformatable 32-channel digital devices with computer-assisted spike and seizure detection raises several unresolved issues. Should patients with nondiagnostic routine EEG receive ambulatory EEG? Is ambulatory EEG as accurate for patients with unclear clinical diagnoses as inpatient video-EEG monitoring? If the diagnostic yield of ambulatory EEG is less than inpatient monitoring, do outpatient savings still make the technique cost-effective? This article reviews the development of ambulatory EEG and the investigations of its clinical utility. An evidence-based analysis explores the benefits and limitations of ambulatory EEG, and offers aspects of its use which require additional clinical research.

Temporal lobe developmental malformations and hippocampal sclerosis: epilepsy surgical outcome

BACKGROUND

Temporal lobe developmental malformations coexist with mesial temporal sclerosis in the form of dual pathology with a high frequency of bilateral amygdala or hippocampal abnormalities.

OBJECTIVE

The aim of this study was to correlate and compare the MRI findings and the surgical outcome in patients with temporal lobe developmental malformations (n = 20) and isolated mesial temporal sclerosis (n = 36).

METHODS

MRI-based normalized volumetry of the amygdala and hippocampal formation in patients with unilateral temporal lobe developmental malformations and isolated mesial temporal sclerosis who underwent temporal lobe resections was performed. Seizure outcome was compared between groups at follow-up.

RESULTS

The frequency of bilateral hippocampal or amygdala atrophy (p < 0.04) and combined hippocampal-amygdala atrophy (p < 0.02) was higher in patients with temporal lobe developmental malformations. Although no significant difference in postsurgical seizure-free status was found between the temporal lobe developmental malformations and isolated mesial temporal sclerosis groups (70% versus 91%), patients with temporal lobe developmental malformations and bilateral amygdala or hippocampal-amygdala atrophy had a significantly worse outcome (p < 0.02).

CONCLUSION

Bilateral hippocampal atrophy is frequent in patients with temporal lobe developmental malformations. However, it is the presence of bilateral amygdala or amygdalo-hippocampal atrophy that is associated with a higher risk of seizure recurrence.

Cognitive effects of topiramate, gabapentin, and lamotrigine in healthy young adults

OBJECTIVE

To study the acute and steady-state cognitive effects of three new antiepileptic drugs (AEDs): gabapentin, lamotrigine, and topiramate.

BACKGROUND

Several newer antiepileptic medications approved recently by the Food and Drug Administration are gaining attention as efficacious alternatives to established AEDs. Greater tolerability with fewer side effects are reported in some. However, the potential cognitive effects of these newer AEDs have received limited attention.

METHODS

Healthy young adults randomized to either of the three drugs were administered tests of attention, psychomotor speed, language, memory, and mood at baseline (predrug), acute single-dose period, and after 2 and 4 weeks on the drug.

RESULTS

Compared with baseline, the topiramate group had selective, statistically significant declines on measures of attention and word fluency at acute doses, whereas the other two AED groups had no performance changes. At the 2- and 4-week test periods, only the topiramate subjects continued to display neurocognitive effects from drug administration.

CONCLUSIONS

Results demonstrate potential acute and steady-state adverse cognitive effects for topiramate, whereas minimal effects were displayed for either gabapentin or lamotrigine in young healthy adults.

Clinical studies of topiramate

Topiramate had well-documented efficacy as an adjunctive agent for partial-onset seizures in 5 double-blind, parallel trials, reducing seizure frequency by 35-47% at 400 mg/day, the optimal dose for most patients. It can also be used as monotherapy for partial-onset seizures. A broad spectrum of action is suggested by studies showing efficacy against a variety of generalized-onset seizure types, including primary generalized tonic-clonic seizures and the component seizures of Lennox-Gastaut syndrome. The major adverse effects of topiramate are of CNS origin. Psychomotor slowing is most common, but disappears in most patients with time or dosage adjustments; 11-28% of patients discontinue the drug because of side effects. No serious skin, liver or blood toxicity has been identified. Efficacy and adverse effect profiles are similar for children and adults. Introduction at rates not exceeding 25-50 mg increases per week will minimize adverse effects and be satisfactory for most adults.

Amygdala atrophy and seizure outcome after temporal lobe epilepsy surgery

Surgical outcome in hippocampal atrophy (n = 44) and amygdalohippocampal atrophy (n = 14) were compared. Hippocampal atrophy had better seizure-free outcome than amygdalohippocampal atrophy (80% versus 50%, p = 0.043). Severity of hippocampal atrophy correlated with duration of epilepsy in patients with hippocampal atrophy (r = 0.4, p = 0.007), but not in those with amygdalohippocampal atrophy, suggesting that these two groups may have a different pathogenesis.

Individual memory change after anterior temporal lobectomy: a base rate analysis using regression-based outcome methodology

PURPOSE

To characterize patterns of base rate change on measures of verbal and visual memory after anterior temporal lobectomy (ATL) using a newly developed regression-based outcome methodology that accounts for effects of practice and regression towards the mean, and to comment on the predictive utility of baseline memory measures on postoperative memory outcome.

METHODS

Memory change was operationalized using regression-based change norms in a group of left (n = 53) and right (n = 48) ATL patients. All patients were administered tests of episodic verbal (prose recall, list learning) and visual (figure reproduction) memory, and semantic memory before and after ATL.

RESULTS

ATL patients displayed a wide range of memory outcome across verbal and visual memory domains. Significant performance declines were noted for 25-50% of left ATL patients on verbal semantic and episodic memory tasks, while one-third of right ATL patients displayed significant declines in immediate and delayed episodic prose recall. Significant performance improvement was noted in an additional one-third of right ATL patients on delayed prose recall. Base rate change was similar between the two ATL groups across immediate and delayed visual memory. Approximately one-fourth of all patients displayed clinically meaningful losses on the visual memory task following surgery. Robust relationships between preoperative memory measures and nonstandardized change scores were attenuated or reversed using standardized memory outcome techniques.

CONCLUSIONS

Our results demonstrated substantial group variability in memory outcome for ATL patients. These results extend previous research by incorporating known effects of practice and regression to the mean when addressing meaningful neuropsychological change following epilepsy surgery. Our findings also suggest that future neuropsychological outcome studies should take steps towards controlling for regression-to-the-mean before drawing predictive conclusions.

Improved health care resource utilization following video-EEG-confirmed diagnosis of nonepileptic psychogenic seizures

The economic burden of epilepsy is well recognized. However, empirical investigation establishing costs associated with the diagnosis and treatment of non-epileptic psychogenic seizures (NEPS) is lacking. We studied 20 patients with video/EEG monitoring-confirmed NEPS to determine the effect of definitive diagnosis and treatment on medical costs and utilization. A medical resource utilization questionnaire and inpatient medical chart review were employed to calculate utilization information. Medication usage, outpatient visits, emergency room admissions, and diagnostic testing over a 6-month pre-diagnosis and a 6-month post-diagnosis period were compared. There was an 84% average reduction in total seizure-related medical charges in the 6 months following NEPS diagnosis. Average diagnostic testing charges declined 76%, average medication charges decreased 69%, outpatient clinic visits declined 80%, and emergency room visits reduced by 97%. A majority of patients obtaining a definitive inpatient video/EEG-seizure-monitoring-confirmed NEPS diagnosis experience substantial reductions in health care utilization and dollar costs.

A comparison of four treatments for generalized convulsive status epilepticus. Veterans Affairs Status Epilepticus Cooperative Study Group

BACKGROUND AND METHODS

Although generalized convulsive status epilepticus is a life-threatening emergency, the best initial drug treatment is uncertain. We conducted a five-year randomized, double-blind, multicenter trial of four intravenous regimens: diazepam (0.15 mg per kilogram of body weight) followed by phenytoin (18 mg per kilogram), lorazepam (0.1 mg per kilogram), phenobarbital (15 mg per kilogram), and phenytoin (18 mg per kilogram). Patients were classified as having either overt generalized status epilepticus (defined as easily visible generalized convulsions) or subtle status epilepticus (indicated by coma and ictal discharges on the electroencephalogram, with or without subtle convulsive movements such as rhythmic muscle twitches or tonic eye deviation). Treatment was considered successful when all motor and electroencephalographic seizure activity ceased within 20 minutes after the beginning of the drug infusion and there was no return of seizure activity during the next 40 minutes. Analyses were performed with data on only the 518 patients with verified generalized convulsive status epilepticus as well as with data on all 570 patients who were enrolled.

RESULTS

Three hundred eighty-four patients had a verified diagnosis of overt generalized convulsive status epilepticus. In this group, lorazepam was successful in 64.9 percent of those assigned to receive it, phenobarbital in 58.2 percent, diazepam plus phenytoin in 55.8 percent, and phenytoin in 43.6 percent (P=0.02 for the overall comparison among the four groups). Lorazepam was significantly superior to phenytoin in a pairwise comparison (P=0.002). Among the 134 patients with a verified diagnosis of subtle generalized convulsive status epilepticus, no significant differences among the treatments were detected (range of success rates, 7.7 to 24.2 percent). In an intention-to-treat analysis, the differences among treatment groups were not significant, either among the patients with overt status epilepticus (P=0.12) or among those with subtle status epilepticus (P=0.91). There were no differences among the treatments with respect to recurrence during the 12-hour study period, the incidence of adverse reactions, or the outcome at 30 days.

CONCLUSIONS

As initial intravenous treatment for overt generalized convulsive status epilepticus, lorazepam is more effective than phenytoin. Although lorazepam is no more efficacious than phenobarbital or diazepam plus phenytoin, it is easier to use.

Topiramate increases cerebral GABA in healthy humans

Topiramate (TOP) is a novel anticonvulsant drug with multiple mechanisms of action used in the treatment of epilepsy. Measurements of cerebral GABA were obtained in six controls using 1H MRS at baseline and at 3 and 6 hours following the administration of 3 mg/kg of TOP. Brain GABA concentrations rose by 72% at 3 hours and by 64% at 6 hours compared with baseline (p < 0.004). This study demonstrates that TOP significantly increases human cerebral GABA concentrations in healthy individuals.

Relative utility of 1H spectroscopic imaging and hippocampal volumetry in the lateralization of mesial temporal lobe epilepsy

OBJECTIVES

To determine the relative utility of 1H MRSI and hippocampal volumetry for the lateralization of mesial temporal lobe epilepsy (MTLE) in patients with intractable epilepsy.

BACKGROUND

MTLE is the most common partial-onset seizure disorder in patients undergoing temporal lobe epilepsy surgery. MR volumetry and spectroscopy are reliable preoperative imaging techniques for the lateralization of MTLE.

METHODS

We analyzed the 1H MRSI and hippocampal formation volumes preoperatively in 30 consecutive patients who had undergone temporal lobectomy.

RESULTS

Volumetry correctly lateralized the side of surgery in 93% of patients and 1H MRSI did so in 97% of patients. Incorrect lateralization occurred by volumetry in two patients and by 1H MRSI in one patient. Concordance between all MRI modalities was 73%. Pearson's analysis revealed no correlation between the degree of hippocampal volume loss and the creatine-to-N-acetylated-compounds ratio.

CONCLUSIONS

Volumetry and 1H MRSI correctly lateralized most patients with MTLE and complement each other in final lateralization. The lack of correlation between the severity of volume loss and the degree of metabolic disturbance suggests that the techniques examine distinct pathophysiologic processes in MTLE.

Contribution of neuropsychological data to the prediction of temporal lobe epilepsy surgery outcome

PURPOSE

We empirically examined the contribution of neuropsychological data to the prediction of postoperative seizure control relative to base rate information in an existing series of patients undergoing anterior temporal lobectomy (ATL).

METHODS

A discriminant function predicting surgery outcome (seizure-free vs. non-seizure-free) was computed separately for samples of patients with left (n = 79) and right (n = 62) temporal lobectomy (LATL, RATL). Predictor variables included 14 measures tapping five neurocognitive domains. The predicted base rates were compared with the actual base rates in the two samples. Finally, overall predictive accuracy was examined in optimal versus suboptimal ATL patients.

RESULTS

The base rate of seizure freedom in the LATL group was 74.70%; that in the RATL group was 66.10%. The predictive function for the LATL group achieved a hit rate of 80.00% and a positive predictive power of 92.11%. The function for the RATL group achieved a hit rate of 83.33% and a positive predictive power (PPP) of 89.66%. The overall predictive accuracy for the optimal group was only 55%, but that in the suboptimal group was 72%.

CONCLUSIONS

Neuropsychological data used in a multivariate statistical fashion may be able to offer an incremental increase in the prediction of postoperative seizure freedom relative to existing base rates of surgery success in patients with ATL epilepsy. The use of neuropsychological data may be of greatest predictive value in a population of ATL candidates with suboptimal findings with a lower base rate of postoperative seizure freedom, but may actually reduce predictive accuracy in a group of ATL candidates from an optimal population with an already high base rate of surgical success.

Volumetric MRI of the limbic system: anatomic determinants

The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system.

Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities

Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p < 0.0001). Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

Congenital porencephaly: MR features and relationship to hippocampal sclerosis

PURPOSE

We determined the frequency of amygdalar-hippocampal atrophy in patients with congenital porencephaly-related seizure disorders to ascertain whether specific MR features of the porencephaly correlate with amygdalar-hippocampal atrophy and epilepsy.

METHODS

We studied brain MR images of 22 patients with congenital porencephaly and measured the volume of the amygdala, the hippocampal formation, and the porencephalic cyst. We then compared imaging features with seizure symptoms.

RESULTS

Porencephaly was unilateral in 20 patients and bilateral in two. Eighteen patients had cortical or subcortical cavitation and four had encephaloclastic changes (noncircumscribed parenchymal destruction associated with cystic components). The porencephaly was located in the middle cerebral artery territory in 12 patients, in the posterior cerebral artery in four, in the internal carotid artery in two, and in multiple vessels in four. The volume of the porencephalic cyst ranged from 1% to 32% of total intracranial volume (mean, 11%). Volumetry detected atrophy of the hippocampal formation in 21 cases (11 unilateral, 10 bilateral) and atrophy of the amygdala in 12 (nine unilateral, three bilateral). No correlation was found between size or location of the porencephaly and degree of hippocampal atrophy. Seizure symptoms correlated with mesial temporal origin but not with cyst location.

CONCLUSION

Amygdalar-hippocampal atrophy often coexists with congenital porencephaly (95%), and the atrophy may be bilateral despite unilateral cysts. Hippocampal structures should be carefully assessed in patients with porencephaly-related seizures.

Association of combined MRI, interictal EEG, and ictal EEG results with outcome and pathology after temporal lobectomy

PURPOSE

Magnetic resonance imaging, interictal scalp EEG, and ictal scalp EEG each have been shown to localize the primary epileptic region in most patients with mesial-basal temporal lobe epilepsy (MBTLE), but the association of surgical outcome and pathology with each combination of these test results is not known.

METHODS

We reviewed the MRI, interictal scalp EEG, and ictal scalp EEG results of 90 consecutive patients with MBTLE. Twelve patients were excluded from the analysis because inconclusive bitemporal intracranial EEG results precluded anterior temporal lobectomy (ATL); none had concordant MRI and interictal scalp EEG results. We compared all combinations of presurgical MRI, interictal EEG, and ictal EEG results to seizure outcome and tissue pathology in the 78 patients who underwent an ATL.

RESULTS

Forty-eight (61%) patients had concordant lateralized MRI and interictal EEG temporal lobe abnormalities, with no discordant ictal EEG results; 77% of these patients were seizure-free after ATL. Concordance of MRI and interictal EEG abnormalities correlated with seizure cessation (p < 0.05), compared to all combinations with discordant or nonlateralizing MRI and interictal EEG results. Mesial temporal sclerosis (MTS) was confirmed pathologically in about 80% of both groups (p = 0.5). Outcome in patients with concordant MRI and ictal EEG with nonlateralizing interictal EEG was significantly worse than combinations with concordant MRI and interictal EEG (p < 0.02).

CONCLUSIONS

Compared to other combinations of test results, concordance of MRI and interictal EEG is most closely associated with surgical outcome in MBTLE. However, most selected patients have pathologic confirmation of MTS regardless of test results or outcome. This information may be useful for planning the presurgical evaluation of patients with medically intractable MBTLE.

Congenital porencephaly and hippocampal sclerosis. Clinical features and epileptic spectrum

We studied clinical features and seizure localization in 14 patients with porencephaly and intractable seizures. Perinatal complications were present in nine patients, childhood febrile convulsions in two, congenital hemiparesis in 12, and intellectual impairment in seven. Ten patients had psychoparetic complex partial seizures (CPS), three had sensorimotor simple partial seizures, and one had generalized tonic-clonic seizures. Surface EEG showed temporal onset in nine patients (one bitemporal) and extratemporal onset in four. MRI showed porencephaly in the distribution of the middle cerebral artery in eight patients, posterior cerebral in three, internal carotid in one, and multiple vessels in two. MR-based volumetry revealed hippocampal formation atrophy in 13 patients (eight unilateral and five bilateral) and amygdalar atrophy in 10 patients (nine unilateral and one bilateral). Hippocampal formation atrophy was concordant with CPS semiology in 10 patients (71%) and with EEG temporal localization in nine patients. Two patients had pathologic confirmation of mesial temporal sclerosis and were seizure free after temporal lobectomy. We conclude that mesial temporal sclerosis often coexists with porencephaly and is the likely seizure focus in the presence of concordant electroclinical data. This recognition implies that effective surgical intervention can be offered to certain patients with porencephaly-related seizure disorders. The dual pathology and association with perinatal cerebral vascular occlusion suggest a common ischemic pathogenesis.

Multimodality MRI in mesial temporal sclerosis: relative sensitivity and specificity

Our objectives were to determine the relative sensitivity and specificity of different MRI sequences and analysis techniques for the detection of mesial temporal sclerosis (MTS). Mesial temporal sclerosis is the most common pathologic finding in patients undergoing temporal lobe epilepsy surgery. Magnetic resonance imaging is the most reliable preoperative imaging technique for the detection of MTS. We analyzed the abnormalities in preoperative MRIs of 44 consecutive patients who had undergone temporal lobectomy and who had pathologic confirmation of MTS. Techniques included inversion recovery (IR); T1-weighted, volume-acquired images; hippocampal T2 relaxometry (HT2); volumetric assessment; and visual analysis. Sensitivity was 86% with IR, 90% with T1-weighted qualitative visual analysis, and 97% with quantitative volumetry. Pathologic prolongation of HT2 (> 2 SD of normal) was present in 79%. Analysis of variance showed statistically significant differences in sensitivity between HT2, volumetric measurements (p < 0.01), and qualitative visual atrophy (p < 0.05). Concordance between all MRI modalities was 68%. Inversion recovery and qualitative analysis lateralized the side of surgery in 93%. The combination of IR and T1-weighted images correctly identify MTS in most patients. Hippocampal volumetry provided localization in an additional small number of patients.

Intrinsic epileptogenesis of hypothalamic hamartomas in gelastic epilepsy

Hypothalamic hamartomas and gelastic seizures are often associated with cognitive deterioration, behavioral problems, and poor response to anticonvulsant treatment or cortical resections. The origin and pathophysiology of the epileptic attacks are obscure. We investigated 3 patients with this syndrome and frequent gelastic seizures. Ictal single-photon emission computed tomography performed during typical gelastic seizures demonstrated hyperperfusion in the hamartomas, hypothalamic region, and thalamus without cortical or cerebellar hyperperfusion. Electroencephalographic recordings with depth electrodes implanted in the hamartoma demonstrated focal seizure origin from the hamartoma in 1 patient. Electrical stimulation studies reproduced the typical gelastic events. Stereotactic radiofrequency lesioning of the hamartoma resulted in seizure remission without complications 20 months after surgery. The functional imaging findings, electrophysiological data, and results of radiofrequency surgery indicate that epileptic seizures in this syndrome originate and propagate from the hypothalamic hamartoma and adjacent structures.

Supplementary sensorimotor area epilepsy. Seizure localization, cortical propagation and subcortical activation pathways using ictal SPECT

We studied clinical signs, EEGs and ictal cerebral blood flow by single-photon emission computed tomography (SPECT) in eight patients with intractable supplementary sensorimotor area (SSMA) seizures. SPECT scans were performed after injection of the regional cerebral blood flow tracer [99mTc]HMPAO (hexametylpropylene amine oxime) early in the ictal phase (2-5 s after seizure onset). Ictal SPECT demonstrated unilateral predominance of hyper-perfusion of the SSMA in all patients, concordant with either lateralizing clinical signs, lateralization of ictal scalp EEG or with the site of ictal onset of seizures, obtained from intracranial electrodes. Two distinctive cortical blood-flow propagation patterns were identified in SSMA seizures. The type I pattern consisted of primary involvement of the ipsilateral SSMA and dorsal premotor and motor cortex. The type II pattern consisted of bilateral but asymmetric mesial frontal propagation. Ictal contraversive head and eye movements were associated with a type I propagation pattern (P < 0.03). Activation of subcortical structures led to variable hyper-perfusion of the basal ganglia and thalamus. Contralateral cerebellar hyperperfusion was observed in all cases. We conclude that ictal SPECT is a useful method for seizure localization in patients with SSMA epilepsy. The observed heterogeneity of clinical features in SSMA epilepsy correlates with propagation to, and activation of, specific cortical structures, and is consistent with known anatomical interconnections between the SSMA, ipsilateral cortical and transcallosal cortical structures.

Epilepsy surgery outcome: comprehensive assessment in children

The effect of extratemporal and temporal lobe cortical resection on children with intractable epilepsy is not well understood. We evaluated a comprehensive array of outcome variables in 33 consecutive children who received epilepsy surgery at 12 years of age or younger. Twenty-two (67%) children were seizure-free, three (9%) had a greater than 90% reduction in seizures, and four had no improvement. Antiepileptic drugs (AEDs) were not required in 10 (30%) children and were reduced in number in another 10. Six (29%) of 21 tested children had an improvement of greater than 10 points in Verbal or Performance IQ after surgery, while one (4%) had a decrease greater than 10 points in Verbal IQ. One mild hemiparesis and one inferior quadrantanopsia occurred; both were anticipated. We used the Child Health Questionnaire (CHQ), a valid and reliable instrument for children, to assess health-related quality of life (HRQOL). Six of 12 subscale scores of the CHQ were significantly lower in the surgical group compared with 410 age-matched control subjects. Parents were satisfied with surgical results in 28 (85%) cases. Pathologic tissue diagnosis and site of resection were not associated significantly with any outcome measure. We conclude that surgery eliminates seizures and reduces AED requirements in most children with intractable epilepsy selected by currently available methods. Further investigation is needed to establish the nature and significance of inferior scores in the surgical group in the HRQOL domains of physical function, general health, and self-esteem.