Postictal psychiatric events during prolonged video-electroencephalographic monitoring studies.

BACKGROUND: Postictal psychiatric events presenting as postictal psychotic events and postictal nonpsychotic events are known to occur following seizure clusters. Accordingly, patients undergoing prolonged video-electroencephalographic (EEG) monitoring studies may be at increased risk of experiencing postictal psychiatric event, as they often have flurries of seizures during these studies. OBJECTIVES: To determine the annual incidence and clinical characteristics of postictal psychotic events and postictal nonpsychotic events in video-EEG monitoring studies in patients with partial seizure disorders and to identify potential pathogenic factors. RESULTS: Thirteen patients met the criteria for a postictal psychiatric event during the 18-month study period, 10 presenting as postictal psychotic events and three as postictal nonpsychotic events. The annual incidence of postictal psychiatric events at our monitoring unit for 1988 was 7.8%, 6.4% presenting as postictal psychotic events and 1.4% as postictal nonpsychotic events. Seven patients had their first-ever postictal psychiatric event during the monitoring study. In 12 of the 13 patients, the postictal psychiatric events mimicked well-defined psychiatric entities of shorter duration (mean, 66.5 hours); they appeared 12 to 72 hours after the last seizure and remitted spontaneously or with the use of low-dose psychotropic medication. No significant differences in EEG, neuroradiologic, psychiatric, medical, or psychosocial data were found between the patients with postictal psychiatric events and a group of 13 age-matched control patients. Follow-up data of comparable duration were available in nine patients with postictal psychiatric events and nine controls. Psychiatric events were reported more frequently by patients with postictal psychiatric events than by control patients (P=.03). In three patients, postictal psychiatric events converted to interictal events. CONCLUSION: These findings suggest that monitoring studies increase the risk for postictal psychiatric events, which neurologists need to be familiar with, as they represent important morbidity associated with these studies.

Complex partial seizures of childhood onset. A five-year follow-up study.

Few detailed studies have examined the long-term outcome of complex partial seizures (CPS) in children and adolescents. Previous studies have selected patients on clinical criteria only or have included those with benign focal epileptiform discharges of childhood, nonepileptiform sharp transients, and generalized epileptiform discharges. We have followed up 29 patients with clinically and electroencephalographically defined CPS of childhood onset for five years or more. Twelve patients are seizure free, eight of them after having epilepsy surgery. Of the remaining, eight patients have intractable seizures. Only one patient was able to discontinue anticonvulsant therapy after epilepsy surgery. No patient had spontaneous remission of seizures without anticonvulsant medications. School difficulties, behavior problems, and unemployment were seen in half the group. We believe CPS in this age group are difficult to control and need aggressive management. In selected patients, epilepsy surgery offers a good chance of seizure control and improvement of educational, social, and vocational potential.

Unilateral blinking: a lateralizing sign in partial seizures.

BACKGROUND: Despite lateralizing signs, clinical lateralization of partial seizures may be difficult. We evaluated the usefulness of ictal unilateral blinking as a new lateralizing sign. METHODS: We retrospectively searched our seizure database over a 30-month period and collected videotapes of patients with ictal unilateral blinking. After initial review, we excluded patients in whom blinking was not clearly unilateral and those in whom it was accompanied by simultaneous facial clonic activity or mouth deviation. All patients underwent prolonged EEG-video monitoring. RESULTS: We identified 14 patients who met the above criteria, for a frequency of 1.5%. Age ranged from 18 months to 50 years (mean, 21.6). There were 11 males and 3 females. Unilateral blinking occurred 0 to 37 seconds (mean, 10) after clinical onset and was visible for 1 to 37 seconds (mean, 17). In 10 patients, other lateralizing signs were present. All patients had partial epilepsy, localized by surface EEG in 10 and by additional invasive EEG in four--nine were left hemisphere (four temporal, four frontal, one not further localized), three right hemisphere (two temporal, one frontal), and two undetermined. Of the 12 patients whose epileptogenic zone was lateralized, blinking was ipsilateral in 10 and contralateral in two. The predictive value of unilateral blinking was 83% against EEG localization. CONCLUSION: Unilateral blinking is a relatively uncommon but reliable lateralizing sign in partial seizures, usually indicating an ipsilateral epileptogenic zone.

Language dominance in patients with early childhood tumors near left hemisphere language areas.

RATIONALE: Language function often develops in the right hemisphere following an acute left hemispheric insult in early childhood. Little is known, however, about lateralization of language function in patients with early childhood tumors near potential left hemisphere language areas. Issues of language dominance are important in the strategy for resection of left temporal and frontal tumors. METHODS: We studied 12 patients who had determination of hemispheric language dominance by the intracarotid amobarbital procedure prior to resection of a left inferolateral frontal or left mid or posterior temporal tumor that (1) was near a classic language area and (2) first manifested with partial seizures by age 6 years (mean, 3.7). RESULTS: Hemispheric language dominance was left in 10 patients (83%), right in one patient, and bilateral in one patient. Six patients with left temporal tumors had localization of Wernicke's area with cortical stimulation, and in five the language area was posterior to the tumor. In one patient, the tumor infiltrated Wernicke's area. Eleven of the 12 patients had complete tumor resection (mean age at operation, 11.8 years) and were seizure-free at follow-up (mean, 3.1 years). Neuropsychological testing showed a tendency for improved language function after operation, and no patient had new overt language deficits. CONCLUSIONS: Early low-grade left frontal and temporal tumors usually did not result in transfer of language dominance to the contralateral hemisphere. Tumors may grow slowly along with the developing brain in young children, with continued left hemisphere language development in regions separate from the neoplasm. Successful tumor resection can be accomplished, but it may require cortical stimulation for localization and sparing of nearby language areas.

Lateralizing signs in intractable partial epilepsy: blinded multiple-observer analysis.

We evaluated the accuracy and interobserver variability of selected ictal and postictal behavioral changes. Three observers, blinded to clinical history, EEG, and side of surgical resection, analyzed videotapes of 166 seizures in 38 patients, looking for lateralizing signs. Twenty-seven patients with temporal lobe resections were seizure-free for > or = 1 year postoperatively, and 11 with extratemporal resections had at least 90% reduction in seizures > or = 1 year postsurgery. The epileptogenic region (ER) was lateralized by analyzing lateralizing signs in 78% of patients; positive predictive value (PPV) was 94% (90% CI = 87% to 100%). Overall kappa was 0.68. Signs were considered present if seen by two or more observers. Forty-five percent had version, ie, forced and sustained head deviation (kappa = 0.76, PPV = 94%); 37% had dystonic posturing of the upper extremity (kappa = 0.47, PPV = 93%); and 34% had unilateral mouth deviation (kappa = 0.83, PPV = 92%). These signs indicated a contralateral ER. Twenty-one percent had unilateral upper extremity automatisms, all ipsilateral to the ER (kappa = 0.65, PPV = 100%); 21% had postictal dysnomia, indicating a dominant-hemisphere ER (kappa = 0.89, PPV = 100%); and 16% had ictal speech, usually indicating a nondominant-hemisphere ER (kappa = 0.75, PPV = 83%). Dystonic posturing, postictal dysnomia, ictal speech, and unilateral upper extremity automatisms may indicate a higher probability of temporal lobe epilepsy. Analysis of lateralizing signs shows good interobserver agreement and provides useful clinical information.

Seizure outcome after functional hemispherectomy for malformations of cortical development.

MRI features were correlated with postsurgical seizure outcome in patients with hemispheric malformations of cortical development (MCD). After functional hemispherectomy, 5 of 6 patients (83%) with hemimegalencephaly had persistent, although markedly improved, seizures; 5 of 6 patients (83%) with relative preservation of part of one lobe or atrophy were seizure free. Hemimegalencephaly and other types of hemispheric MCD appear to differ in prognosis for freedom from seizures after functional hemispherectomy.

Intractable epilepsy in vascular congenital hemiparesis: clinical features and surgical options.

Forty-one patients with vascular congenital hemiplegia and intractable epilepsy were reviewed. Most had severe hemiparesis, mental retardation, porencephaly, and focal epilepsy. Thirty-three were considered surgical candidates and 25 underwent surgery. Seizure freedom and significant seizure reduction were achieved in 12 of 13 patients after functional hemispherectomy, 4 of 6 after temporal lobectomy, 2 of 2 with extratemporal focal resections, 1 of 3 with corpus callosotomy, and 1 with porencephalic cyst drainage.

Seizure symptomatology in infants with localization-related epilepsy.

The clinical characteristics of seizures in adults and children with localization-related epilepsy have been clearly described and classified, but few data are available based on video EEG studies of postneonatal infants under 2 years of age. We analyzed 125 videotaped seizures from 23 infants aged 2 to 24 months with localization-related epilepsy defined by localized ictal EEG or localized lesion on neuroimaging with seizure-free surgical outcome. Seizure symptomatology was classified based on observable behavioral and motor manifestations and then correlated with location of the epileptogenic zone. Seizures characterized by decrease in behavioral motor activity with indeterminate level of consciousness and minimal or no automatisms ("hypomotor" seizures) arose from temporal, temporoparietal, or parieto-occipital regions (7 patients). Seizures with localized or bilateral clonic, tonic, or atonic motor phenomena arose predominantly from frontal, frontocentral, central, or frontoparietal areas (12 patients). One patient had versive seizures arising from the contralateral occipital lobe, 2 patients had infantile spasms (one with a frontal tumor, one with temporo-parieto-occipital dysplasia), and one patient had unclassifiable seizures. Disruption of temporal or temporoparietal function resulted primarily in diminution of behavioral activity, whereas ictal activation of motor areas during frontal or central onset seizures resulted mainly in localized or generalized motor phenomena. Infantile spasms occurred because of lesions in either location. Using an approach based on easily observable behavioral and motor phenomena, it was possible to classify the seizures in all but one infant.

Dystonic posturing in complex partial seizures of temporal lobe onset: a new lateralizing sign.

We observed unilateral dystonic posturing of an arm or leg in 41 complex partial seizures (CPS) from 18 patients. In all cases this was contralateral to the ictal discharge. Unilateral automatisms occurred in 39 of 41 seizures on the side opposite the dystonic limb. Version occurred in 11 of the 41 CPS to the same side as the dystonic posturing and always followed the posturing. Subdural recordings of seven seizures showed ictal onset from the mesial basal temporal lobe. At the onset of dystonic posturing, maximum ictal activity was in the basal temporal lobe with minimal involvement of the cerebral convexity. Unilateral dystonic posturing occurs frequently in CPS of temporal lobe onset and is a lateralizing sign with a high degree of specificity. It probably reflects spread of the ictal discharge to basal ganglia 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.

Temporal lobe epilepsy due to hippocampal sclerosis in pediatric candidates for epilepsy surgery.

OBJECTIVE: To characterize the clinical, EEG, MRI, and histopathologic features and explore seizure outcome in pediatric candidates for epilepsy surgery who have temporal lobe epilepsy (TLE) caused by hippocampal sclerosis (HS). METHODS: The authors studied 17 children (4 to 12 years of age) and 17 adolescents (13 to 20 years of age) who had anteromesial temporal resection between 1990 and 1998. RESULTS: All patients had seizures characterized by decreased awareness and responsiveness. Automatisms were typically mild to moderate in children and moderate to marked in adolescents. Among adolescents, interictal spikes were almost exclusively unilateral anterior temporal, as opposed to children in whom anterior temporal spikes were associated with mid/posterior temporal, bilateral temporal, extratemporal, or generalized spikes in 60% of cases. MRI showed hippocampal sclerosis on the side of EEG seizure onset in all patients. Fifty-four percent of children and 56% of adolescents had significant asymmetry of total hippocampal volumes, whereas the remaining patients had only focal atrophy of the hippocampal head or body. Subtle MRI abnormalities of ipsilateral temporal neocortex were seen in all children and 60% of adolescents studied with FLAIR images. On histopathology, there was an unexpectedly high frequency of dual pathology with mild to moderate cortical dysplasia as well as HS, seen in 79% of children and adolescents. Seventy-eight percent of patients were free of seizures at follow-up (mean, 2.6 years). A tendency for lower seizure-free outcome was observed in patients with bilateral temporal interictal sharp waves or bilateral HS on MRI. The presence of dual pathology did not portend poor postsurgical outcome. CONCLUSIONS: TLE caused by HS similar to those in adults were seen in children as young as 4 years of age. Focal hippocampal atrophy seen on MRI often was not reflected in total hippocampal volumetry. Children may have an especially high frequency of dual pathology, with mild to moderate cortical dysplasia as well as HS, and MRI usually, but not always, predicts this finding. Postsurgical seizure outcome is similar to that in adult series.

Seizure outcome after surgery for epilepsy due to malformation of cortical development.

PURPOSE: To explore seizure outcome after surgery for focal epilepsy due to malformation of cortical development (MCD), with focus on the role of MRI. METHODS: Thirty-five patients who had surgery for intractable focal epilepsy due to MCD identified by preoperative MRI and confirmed by histopathologic analysis of resected tissue were studied. Patients were aged 3 months to 47 years (median, 14 years) at the time of surgery. Duration of follow-up was 1 to 7.9 (mean, 3.4) years. RESULTS: At latest follow-up, 17 patients (49%) had Engel Class I outcome with no seizures or auras only; eight patients (23%) had Class II outcome, with rare disabling seizures; seven patients (20%) had worthwhile improvement; and three patients (9%) had no improvement. Seizure-free outcome tended to be more frequent among patients who had complete resection of unilateral MCD (excluding hemimegalencephaly) based on postoperative MRI (7/12; 58%), compared with patients with unilateral MCD who had incomplete resection (3/11; 27%), but the difference was not significant. The frequency of seizure-free outcome did not differ significantly between children (8/14; 57%), adolescents (7/15; 47%) or adults (2/6; 33%); between patients who had daily (12/24; 50%), weekly (4/9; 44%), or monthly (1/2; 50%) seizures preoperatively; between patients who had temporal (2/6; 33%) or extratemporal or multilobar resections (14/28; 50%); or between patients who were (9/16; 56%) or were not (8/19; 42%) studied with subdural electrodes. Results for all analyses were similar when analyzed at latest available follow-up or at 1 year after surgery. CONCLUSIONS: Surgery can offer seizure-free outcome for approximately one half of carefully selected patients with intractable focal epilepsy due to MCD. Complete resection of the MRI-apparent lesion may improve the likelihood for favorable outcome. MRI evidence of hemimegalencephaly or bilateral MCD suggests a low likelihood for postoperative freedom from seizures.

Complications of invasive video-EEG monitoring with subdural grid electrodes.

OBJECTIVE: To evaluate the risk factors, type, and frequency of complications during video-EEG monitoring with subdural grid electrodes. METHODS: The authors retrospectively reviewed the records of all patients who underwent invasive monitoring with subdural grid electrodes (n = 198 monitoring sessions on 187 patients; median age: 24 years; range: 1 to 50 years) at the Cleveland Clinic Foundation from 1980 to 1997. RESULTS: From 1980 to 1997, the complication rate decreased (p = 0.003). In the last 5 years, 19/99 patients (19%) had complications, including two patients (2%) with permanent sequelae. In the last 3 years, the complication rate was 13.5% (n = 5/37) without permanent deficits. Overall, complications occurred during 52 monitoring sessions (26.3%): infection (n = 24; 12.1%), transient neurologic deficit (n = 22; 11.1%), epidural hematoma (n = 5; 2.5%), increased intracranial pressure (n = 5; 2.5%), and infarction (n = 3; 1.5%). One patient (0.5%) died during grid insertion. Complication occurrence was associated with greater number of grids/electrodes (p = 0.021/p = 0.052; especially >60 electrodes), longer duration of monitoring (p = 0.004; especially >10 days), older age of the patient (p = 0.005), left-sided grid insertion (p = 0.01), and burr holes in addition to the craniotomy (p = 0.022). No association with complications was found for number of seizures, IQ, anticonvulsants, or grid localization. CONCLUSIONS: Invasive monitoring with grid electrodes was associated with significant complications. Most of them were transient. Increased complication rates were related to left-sided grid insertion and longer monitoring with a greater number of electrodes (especially more than 60 electrodes). Improvements in grid technology, surgical technique, and postoperative care resulted in significant reductions in the complication rate.

Psychogenic seizures in children and adolescents: outcome after diagnosis by ictal video and electroencephalographic recording.

Psychogenic seizures in 21 nonepileptic children and adolescents, aged 8 to 18 (mean 14.5) years, were recorded by means of video recording and electroencephalography. The episodes included thrashing movements, limb jerking, or staring, with unresponsiveness. Ictal and interictal electroencephalograms showed no abnormalities after antiepileptic medication was discontinued. Fifteen patients had psychogenic seizures spontaneously during recording, and six had seizures in response to suggestion and intravenous saline injection. After the video-electroencephalographic evaluation, patients and families were told that the episodes were emotional in origin. All patients but 1 agreed to remain without antiepileptic medication, and 16 patients (76%) agreed to begin psychiatric treatment. At 6 to 66 (mean 30) months' follow-up, 14 of 18 (78%) were free of episodes. These data indicate that the majority of young patients with psychogenic seizures have a good outcome. A firm diagnosis is critical so that the episodes can be classified and emphasized as medically not worrisome, permitting a shift away from antiepileptic medication and toward psychiatric treatment.

Psychiatric features of children and adolescents with pseudoseizures.

BACKGROUND: Pseudoseizures may occur as a somatoform disorder in children and adolescents as well as adults. However, few data are available about psychiatric features or outcome in pediatric patients. PATIENTS AND METHODS: We studied 34 patients (25 girls [74%]) who were evaluated by a child psychiatrist at our institution immediately after diagnosis of pseudoseizures by ictal video electroencephalogram (EEG) at ages 9 to 18 years (mean age, 14 years). Each patient had at least 1 pseudoseizure recorded by video EEG that was judged by the patient and family as typical, characterized by unresponsiveness plus limb twitching or limpness and other features, with EEG showing persistence of normal cortical background rhythms. RESULTS: In addition to conversion disorder, 11 patients (32%) had mood disorders including major depression, bipolar disorder, or dysthymic disorder, usually with severe psychosocial stressors. Eight children (24%) had separation anxiety and school refusal with moderate psychosocial stressors. Two patients (6%) had brief reactive psychosis or schizophreniform disorder. A few (1-3) patients each had panic disorder, overanxious disorder, adjustment disorder, oppositional/defiant disorder, or impulse control disorder. Four patients (12%) also had personality disorders. Eleven patients (32%) had a history of sexual abuse. This was especially frequent in the subgroup with mood disorders (7 [64%] of 11 patients). Fifteen patients (44%) had severe family stressors including recent parental divorce, parental discord, or death of a close family member. Two patients (6%) had a history of physical abuse. Freedom from pseudoseizures for the preceding 9 to 55 months (mean, 30 months) was achieved for 15 (72%) of the 21 patients who could be reached for telephone follow-up. For 8 (53%) of these 15 patients, the last pseudoseizure was within 1 month of diagnosis by video EEG. CONCLUSIONS: Major mood disorders and severe environmental stress, especially sexual abuse, are common among children and adolescents with pseudoseizures and should be considered in every case. A subgroup of children with separation anxiety and school refusal had less severe psychiatric problems and moderate psychosocial stressors. Clear diagnosis by video EEG, together with prompt psychiatric evaluation and treatment, may result in freedom from pseudoseizures for most children and adolescents.

Periodic limb movements and sleep apnoea.

This study investigated the relationship of Periodic Leg Movements (PLMs) to the severity of Obstructive Sleep Apnoea (OSA) in 52 patients. In addition the prevalence of PLMs in OSA was compared with two other patient populations: narcolepsy and idiopathic PLM disorder (n = 38). All patients were between 20 and 50 years in age and were compared with a control group of 88 asymptotic paid volunteers aged between 20 and 50. PLMs were scored when tibialis anterior EMG activity lasted 0.5-5.0 s with an amplitude of at least half that of pre-sleep voluntary ankle dorsiflexion and when they were part of 4 or more consecutive events separated by 20-90 s. The prevalence of PLMs in OSA was 27.6%, which was similar to the prevalence in our normal controls of 20.5%. However, in the OSA group the majority of the PLMs occurred in the mild OSA patients (40.7%). This was similar to the prevalence of PLMs in narcoleptics (50%). The prevalence of PLMs in moderate OSA, was 24.5%; similar to that of normal controls. In severe OSA, PLMs were also low (12.5%). There is an inverse relationship between PLMs and the severity of OSA. The greater number of arousals and awakenings associated with respiratory irregularities seen in the severe OSA group produced an equivocal manifestation of PLMs.

Multiple sleep latency test and polysomnography in diagnosing Kleine-Levin syndrome and periodic hypersomnia.

Kleine-Levin syndrome and periodic hypersomnia are often misdiagnosed initially because there is no objective test for these conditions. To determine the value of the Multiple Sleep Latency Test and polysomnography in this respect, the authors studied four patients with Kleine-Levin syndrome or periodic hypersomnia who had taken the Multiple Sleep Latency Test and undergone polysomnography during the symptomatic episode and/or during the asymptomatic interval. During but not between symptomatic episodes, the Multiple Sleep Latency Test revealed abnormal sleep latencies in all patients, and polysomnography revealed increased rapid eye movement propensity in one patient and a reduction in delta-sleep in two patients. In conclusion, the Multiple Sleep Latency Test and polysomnography are useful in diagnosing Kleine-Levin syndrome and periodic hypersomnia, especially when administered in a standardized fashion during and after the symptomatic period. The authors recommend that polysomnography and the Multiple Sleep Latency Test be performed no earlier than the second night after the onset of a symptomatic episode and the following day to reveal maximal hypersomnolence, and more than 2 weeks after a symptomatic episode to represent the asymptomatic interval.

Psychomotor seizures of temporal lobe onset: analysis of symptom clusters and sequences.

We analyzed 91 psychomotor seizures from 31 patients seizure free at least one year after temporal lobectomy (implying temporal lobe onset). Fifty symptoms were looked for in every seizure and their time of onset and ending noted. Statistical analysis was used to define symptom clusters and the order of appearance of symptoms. Of the eighteen most common symptoms examined, all of these symptoms form a tight cluster showing a high degree of correlation. Within this cluster, there was a tendency towards the following subclusters: (a) epigastric aura, ictal vomiting, alimentary and hand automatisms; (b) behavioral arrest, complete loss of consciousness, staring and bilateral facial contraction; (c) unilateral dystonic posturing of an arm, mimetic automatisms, complex gestures, ictal speech and partial loss of consciousness; (d) looking around, agitation, vocalizations and whole body movements. We also found a strong correlation between epigastric sensation and ictal vomiting in psychomotor seizures arising from the right but not the left temporal lobe. The commonest sequence of symptoms was: behavioral arrest followed by alimentary and hand automatisms, looking around and whole body movements, in that order.

Hippocampal volumetry in children 6 years or younger: assessment of children with and without complex febrile seizures.

PURPOSE: To study the relationship of complex febrile seizures (CFS) in the evolution of mesial temporal sclerosis. METHODS: We studied five children 22-68 (mean 44) months old with MRI volumetry 2 days-46 months after their first CFS, and compared total hippocampal volumes and right to left hippocampal volume ratios to those of 11 controls, 15-83 (mean 55) months old, who had MRI for complaints which turned out to be neurologically insignificant. RESULTS: In control children, total hippocampal volumes increased linearly with age, while right to left hippocampal volume ratios tended to decrease with age. In children with CFS total hippocampal volumes tended to be smaller than in controls. Right to left ratios were greater than 1 in all five children with CFS compared to seven of 11 controls. Hippocampal asymmetry was noted in only one child, with the right to left volume ratio exceeding two standard deviations from the control mean. The MRI of this child also demonstrated a subarachnoid cyst in the left frontocentral region, ipsilateral to the smaller hippocampus. Visual inspection of the remaining patients revealed no definite structural cortical abnormalities. None of the children developed subsequent afebrile seizures during the brief follow-up period. CONCLUSIONS: Hippocampal volumetry in controls revealed a linear increase in total hippocampal volumes and a statistically nonsignificant trend toward reduced right larger than left hippocampal ratios between 17 and 83 months old. The tendency for smaller total hippocampal volumes and larger right to left hippocampal volume ratios in children with CFS compared to controls could suggest a developmental abnormality, injury during CFS, or be age-related. The significant hippocampal asymmetry in a single child with CFS suggests that age may not be a factor in every case. Further studies are needed to collect control data in young children as well as prospectively follow children with CFS with serial imaging to better understand the relationship between CFS and the evolution of hippocampal atrophy.

Benign myoclonus of early infancy: an imitator of West's syndrome.

Benign myoclonus of early infancy is a rare condition characterized by nonepileptic spasms that may resemble the epileptic spasms seen in West's syndrome. The spells in benign myoclonus of early infancy begin before age 1 year and are self-limited. The electroencephalogram (EEG) is invariably normal, and neurologic development is not affected. West's syndrome is characterized by infantile spasms that appear before 1 year of age, an abnormal EEG with hypsarrhythmia, and a poor prognosis. We describe six infants who presented for evaluation of clusters of head, trunk or extremity spasms, eye blinking, brief jerking of upper extremities or trunk, and head nodding episodes. In most, a presumptive diagnosis of West's syndrome was made prior to the referral. One infant had been placed on valproate. Routine EEG recordings or prolonged video EEG monitoring were normal both during and between episodes. After the negative evaluations, the diagnosis of benign myoclonus of early infancy was made in each infant. Subsequently, no infant was treated with anticonvulsants. Follow-up revealed complete resolution of the episodes in all children within 2 weeks to 8 months of onset. All had normal neurologic development. Based on our cases and review of the literature, the prognosis for this disorder is excellent. Care should be taken to recognize this rare entity and avoid unnecessary and potentially harmful antiepileptic therapy.