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Correctly classifying seizures is essential for appropriate epilepsy management. Focal and generalized epilepsy rarely occur independently in the same patient. Cases of focal ictal evolution during seizures that are generalized in onset have been reported though these have included a small heterogeneous series of patients with generalized epilepsy and features on the EEG. We wish to report two patients with absence epilepsy that were noted on video-EEG monitoring to manifest a focal temporal electroclinical transformation from a typical absence seizure. Defining the electroclinical spectrum of absence seizures could add to our understanding of the selective cortical and subcortical networks that are involved in patients with "prototypic" generalized and focal seizures., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Quantitative MRI techniques have demonstrated thalamocortical abnormalities in idiopathic generalized epilepsy (IGE). However, there are few studies examining IGE early in its course and the neurodevelopmental course of this region is not adequately defined., Objective: We examined the 2-year developmental course of the thalamus and frontal lobes in pediatric new-onset IGE (i.e., within 12 months of diagnosis)., Methods: We performed whole-brain MRI in 22 patients with new-onset IGE and 36 age-matched healthy controls. MRI was repeated 24 months after baseline MRI. Quantitative volumetrics were used to examine thalamic and frontal lobe volumes., Results: The IGE group showed significant differences in thalamic volume within 1 year of seizure onset (baseline) and went on to show thalamic volume loss at a significantly faster rate than healthy control children over the 2-year interval. The control group also showed a significantly greater increase in frontal white matter expansion than the IGE group. In contrast, frontal lobe gray matter volume differences were moderate at baseline and persisted over time, indicating similar developmental trajectories with differences early in the disease process that are maintained., Conclusions: Brain tissue abnormalities in thalamic and frontal regions can be identified very early in the course of IGE and an abnormal trajectory of growth continues over a 2-year interval.

Objective: To make evidence-based recommendations concerning the evaluation of the child with a nonprogressive global developmental delay., Methods: Relevant literature was reviewed, abstracted, and classified. Recommendations were based on a four-tiered scheme of evidence classification., Results: Global developmental delay is common and affects 1% to 3% of children. Given yields of about 1%, routine metabolic screening is not indicated in the initial evaluation of a child with global developmental delay. Because of the higher yield (3.5% to 10%), even in the absence of dysmorphic features or features suggestive of a specific syndrome, routine cytogenetic studies and molecular testing for the fragile X mutation are recommended. The diagnosis of Rett syndrome should be considered in girls with unexplained moderate to severe developmental delay. Additional genetic studies (e.g., subtelomeric chromosomal rearrangements) may also be considered in selected children. Evaluation of serum lead levels should be restricted to those children with identifiable risk factors for excessive lead exposure. Thyroid studies need not be undertaken (unless clinically indicated) if the child underwent newborn screening. An EEG is not recommended as part of the initial evaluation unless there are historical features suggestive of epilepsy or a specific epileptic syndrome. Routine neuroimaging, with MRI preferred to CT, is recommended particularly if abnormalities are found on physical examination. Because of the increased incidence of visual and auditory impairments, children with global developmental delay may undergo appropriate visual and audiometric assessment at the time of diagnosis., Conclusions: A specific etiology can be determined in the majority of children with global developmental delay. Certain routine screening tests are indicated and depending on history and examination findings, additional specific testing may be performed.

Semipermanent venous catheters remain the most commonly used access for chronic hemodialysis (HD) in pediatric patients. The recent availability of Tesio catheters in 7 and 10 F has expanded available HD catheter options for children and adolescents. We report our experience with Tesio catheter survival, complications, and effect on dialysis adequacy in comparison to standard dual-lumen (DL) catheters in our pediatric HD patients. Demographic data were similar between the two groups. Overall actuarial survival was significantly longer for Tesio versus DL catheters (46% versus 0% at 1 year; P = 0.003). A comparison of smaller catheters (7 F Tesio catheter, 8 or 10 F DL catheter) showed that smaller Tesio catheters had a significantly longer survival (median survival, 244 versus 13 catheter-days; P < 0.01). Tesio 10 F catheters also survived significantly longer than the larger 11.5 and 12 F DL catheters (P < 0.02). Catheter sepsis occurred less frequently with Tesio catheters (one episode/20 catheter-months) than DL catheters (one episode/5 catheter-months) despite the longer duration of Tesio catheters. Adequate dialysis (single-pool Kt/V > 1.2) was delivered with the same frequency, but for a longer duration with Tesio catheters (76% +/- 32% over 100 monthly measurements versus DL catheter, 57% +/- 45% over 54 monthly measurements). Our clinical practice was to replace cuffed catheters when adequate dialysis could not be delivered. We conclude that Tesio catheters provide superior performance compared with DL catheters in terms of catheter survival, infection rates, and duration of adequate performance.

Ictal laughter is a relatively unusual phenomenon that appears to arise from within hypothalamic hamartomas. Gelastic seizures of neocortical origin are rare and when reported typically originate from temporofrontal regions in proximity to the hypothalamus, raising the possibility of a subtle lesion in the hypothalamus. A girl with gelastic seizures originating in a dysembryoblastic neuroepithelial tumor at the cranial vertex had resolution of her seizures following surgical resection. Electrical propagation of seizures via the cingulate gyrus appears to be an alternative mechanism underlying gelastic seizures.

Epilepsy surgery in children requires a multidisciplinary approach. This section examines the role of scalp EEG, video-EEG monitoring, and intracranial EEG in the presurgical evaluation. Concepts central to understanding the basis for surgical treatment, such as the epileptogenic zone, the irritative zone, and the epileptogenic lesion, are discussed. An illustrative case then demonstrates application of the process in clinical practice. Neuroimaging and neuropsychological issues are not discussed herein; rather they are addressed elsewhere in this issue.

Neuroimaging and the neuropsychological evaluation are important components of the presurgical evaluation for epilepsy surgery. Advances in neuroimaging over the last decade, to a large part, underlie improvements in pediatric epilepsy surgery outcomes. The neuropsychological evaluation plays an important role in the evaluation of the older child and adolescent, particularly in the evaluation of mesial temporal sclerosis. However, its role in the young child being considered for surgery remains to be defined. This section reviews the definition of medical intractability, issues related to medication withdrawal during video-EEG monitoring, recent neuroimaging advances, and the neuropsychological evaluation.

Isolated deposition of the third component of complement (C3) in the renal arterioles has been noted on biopsy specimens in patients with hematuria. This entity is of little known significance and reports of this finding in pediatric patients with hematuria are rare. We reviewed the clinical histories and biopsies of 17 children with hematuria and vascular C3 deposition on biopsy at Texas Children's Hospital over an 14-year period. The mean age of presentation was 10.8 (range 4.5-16.6) years with a male preponderance (71%). Family history for hematuria was positive in 6 of 17 patients (35%). Light microscopy was normal or showed only minor abnormalities. Immunofluorescence was negative for IgA and IgG in all patients. Seven patients (41.1%) were noted to have diffuse or focally thin basement membranes on electron microscopy in addition to positive C3 immunofluorescence. The mean follow-up time was 23.8 months, during which 2 of 17 patients (12%) developed worsening proteinuria. The etiopathogenesis of this condition remains unclear, but an underlying immunological process cannot be ruled out. It is possible that this condition represents a stage of an acute glomerulonephritis. Clinical follow-up of these patients is warranted, as the long-term prognosis remains unclear.

Cefepime is a fourth-generation cephalosporin widely used for gram-negative sepsis. The authors report two patients in whom nonconvulsive status epilepticus developed while they were on treatment with cefepime for Pseudomonas aeruginosa infection. The status epilepticus resolved completely once the drug was withdrawn. Cefepime therapy can result in status epilepticus, especially if given in higher doses than required.

Objective: To review the pharmacology, pharmacokinetics, efficacy, and adverse effects of vigabatrin and its role in the management of seizure disorders., Methods: A MEDLINE search of English-language literature from January 1993 through January 1999 was conducted using vigabatrin as a search term to identify pertinent studies and review articles. Additional studies were identified from the bibliographies of reviewed literature. The manufacturer provided postmarketing surveillance data. Priority was given to randomized, double-blind, placebo-controlled studies., Findings: Vigabatrin is a selective and irreversible inhibitor of gamma-aminobutyric acid transaminase. In controlled clinical trials of vigabatrin add-on therapy in patients with uncontrolled partial seizures, 24-67% of patients achieved a < or =50% reduction in seizure frequency. Data from two comparative trials with carbamazepine monotherapy indicate that vigabatrin monotherapy reduces the frequency of partial seizures in patients with newly diagnosed epilepsy. Vigabatrin also controls infantile spasms, particularly those associated with tuberous sclerosis. Vigabatrin is more effective in patients with partial seizures than in those with generalized seizures. The drug is generally well tolerated. Headache and drowsiness were the most common adverse effects observed in controlled clinical trials; visual field defects, psychiatric reactions, and hyperactivity also have been reported. There are no known clinically significant drug interactions., Conclusions: Vigabatrin improves seizure control as add-on therapy for refractory partial seizures and may produce therapeutic benefits in the treatment of infantile spasms. Vigabatrin is generally well tolerated, with a convenient administration schedule, a lack of known significant drug interactions, and no need for routine monitoring of plasma concentrations.

Central nervous system arteriovenous malformations typically present with chronic neurologic impairment. An 8-year-old boy presented with acute spinal cord infarction associated with a spinal arteriovenous malformation. Vascular steal phenomenon suggested by spinal angiography happens to underly the pathogenic mechanism.

Respiration and suck are gestational age-dependent reflexes modulated in the brain stem. To determine if the suck reflex pattern could be used to predict apnea, the relationship between the two was examined in 28 neonates. The suck reflex was quantified with respect to burst-pause rhythm, amplitude of negative suck pressure, and synchrony of the negative-positive pressure. Apneas were counted 5 days prior to and following measurement of the suck reflex pattern. Increasing gestational age correlated with a lower frequency of apnea (P < .01) and higher suck scores (P < .01). A mature suck reflex pattern, however, failed to predict the occurrence of apnea.

A 13-year-old girl of normal intellect had clinically silent occipital electrographic status epilepticus that persisted for more than 3 years. Neurologic examination and cranial magnetic resonance imaging were entirely normal. [18F]Fluorodeoxyglucose positron emission tomography demonstrated a hypermetabolic focus in the right occipital lobe. Electrographic status lasting years can be seen in epilepsia partialis continua. However, the absence of focal clinical seizures, nonprogressive course, and normal magnetic resonance imaging study seen in this patient are not features characteristic of epilepsia partialis continua.

Botulism in infants, unless recognized early, is associated with high mortality and morbidity. The diagnosis is suspected when infants present with sudden onset of weakness, respiratory failure, and constipation and is confirmed by demonstration of botulinum toxin in stool several weeks later. Electrodiagnosis allows quick and reliable confirmation of botulism. Low-amplitude compound muscle action potentials, tetanic or post-tetanic facilitation, and the absence of post-tetanic exhaustion support the diagnosis. Two infants with confirmed botulism did not exhibit the characteristic electrodiagnostic features, demonstrating the pitfalls in electrodiagnosis of infantile botulism.

Objective: To examine the influence of gestational age on seizures in the neonatal intensive care unit., Study Design: A cohort of 4165 neonates admitted to a university intensive care unit between 1986 and 1995. The incidence, time of onset, and etiology of neonatal seizures in the cohort were distributed by gestational age. Logistic regression and t test were used to examine the relationship between gestational age and seizures in the neonatal intensive care unit., Results: Seizures occurred in 356 (8.6%) infants. The seizure rate was parabolically related to gestational age, such that infants at 30 to 36 weeks' gestation had a 4.8% rate compared with 11.9% and 14.1% rates for infants < 30 and > 36 weeks, respectively (p < 0.001). Seizures manifested earlier in infants < 30 weeks (2.3 +/- 5.6 days of life) and > 36 weeks (3.7 +/- 8.7 days) gestational age compared with neonates 30 to 36 weeks (10.4 +/- 14.5 days) (p < 0.001). Intraventricular hemorrhage was the principal etiology underlying the higher seizure rate for infants < 30 weeks (p < 0.001). Hypoxic-ischemic encephalopathy and congenital malformations were primary factors for infants > 36 weeks (p < 0.01). Nervous system infections were evenly distributed across gestational age., Conclusion: Gestational age exerts a considerable influence on the incidence, onset, and etiology of neonatal seizures.

The electroencephalogram (EEG) is confirmatory in 70% of children and adults with seizures, although gestation- and etiology-specific EEG confirmatory rates in neonates have not been well defined. All neonates treated for seizures and who underwent EEG were identified from 4,575 neonates admitted between 1985 and 1996 to a neonatal intensive care unit. The relationship between EEG findings (epileptiform discharges and background abnormalities) and gestation, mortality rate, and seizure etiology was examined using the Student t test. One hundred eighty-three neonates treated for seizures underwent a total of 352 EEGs: 144 of these neonates (79%) had an abnormal EEG (epileptiform discharges in 113 (60%) and nonepileptiform background abnormalities in 31). The EEG confirmatory rate increased with gestation (63% at 28 weeks vs 77% at term, P < 0.02). Etiology for seizures also influenced the EEG confirmatory rate: central nervous system (CNS) infection 95% (P < 0.05), hypoxic-ischemic encephalopathy 80% (P < 0.05), germinal matrix-intraventricular hemorrhage 65%, and CNS malformations 65%. The EEG confirmatory rate was predictive of neonatal mortality (19% vs 6%, P < 0.03). The EEG was directly confirmatory (epileptiform discharges) in 60% and supportive (nonepileptiform background abnormalities) in a further 17% of neonates with seizures. Gestation and etiology influence the EEG confirmatory rate in neonatal seizures.

A child with basilar artery occlusion in the neonatal period is reported. The occlusion was documented by unenhanced computed tomography performed in the neonatal period demonstrating a "dense" artery at the tip of the basilar artery. The pattern of cerebral damage on MRI scan at 10 years of age confirmed the site of the vascular occlusion. The evidence suggests that embolization was the operating pathogenic mechanism of cerebral vascular occlusion. Neonatal arterial thrombosis involving the carotid circulation has been well documented and may be due to many pathological factors including direct trauma to the carotid artery and embolization from remote sites. Thrombosis of the vertebral artery in the neonate is only rarely reported and only in association with significant cervical trauma. A second child with a similar pattern of cerebral injury demonstrated on neuroimaging is described suggesting that this event may be more common than recognized. The clinical features of basilar artery occlusion as seen in the adult are not apparent in the neonate. Recognition of the neuroimaging characteristics seen in this condition may help to provide the clinician with a reasonable pathogenetic explanation for unexplained cerebral injury.

Neonatal intensive care unit survival rates have improved significantly over the past decade. This improvement primarily reflects declining mortality rates among preterm infants. Neurologic morbidity increases with prematurity and is the major predictor of long-term disability. Accordingly, concern has been expressed that the burden of neurologic dysfunction among contemporary neonatal intensive care unit survivors may be increasing. To define the trends of neurologic disorders in the contemporary neonatal intensive care unit, all 4164 admissions between 1986 and 1995 to a tertiary neonatal intensive care unit were examined. Neonatal intensive care unit admissions (413 +/- 49 per year), proportion of births at less than 37 weeks (70 +/- 3% per year), and referral patterns were stable between 1986 and 1995. Over the study period, 773 (18%) of 4164 neonatal intensive care unit infants had a total of 1062 neurologic disorders. The neonatal intensive care unit mortality rate declined from 12% in 1986 to 4.2% in 1995 (P < .01). Neurologic disorders declined, from 27% of infants born in 1986 to 12% in 1995 (P < .001): 356 had seizures (14% in 1986 to 4% in 1995; P < .001), 235 had hypoxic-ischemic encephalopathy (8% in 1986 to 4% in 1995, P < .01), and 167 had intraventricular hemorrhage (7% in 1986 to 1.4% in 1995, P < .005). Frequency of congenital or chromosomal aberration affecting the nervous system was relatively constant (4.5% per year). Despite a three-fold improvement in neonatal intensive care unit survival between 1986 and 1995, the frequency of perinatally acquired neurologic disorders declined by more than 50%.

The incidence of germinal matrix-intraventricular hemorrhages declined from 50% in 1977 to 24% in 1985. Over the last decade intraventricular hemorrhage rates ranging from 8% to 56% were reported, leaving uncertainty as to the direction of recent intraventricular hemorrhage trends. Records of all 1950 neonates weighing 2250 g or less at birth (867 weighing 1500 g or less and 1083 weighing 1501-2250 g) at a university neonatal intensive care unit between 1986 and 1995 were studied. Intraventricular hemorrhage rate declined by 53%, from 11.5% in 1986 to 5.5% in 1995 (P < .01), and was consistent across all birthweight groups: 750 g or less from 36% to 24%, 751-1000 g from 38% to 22%, 1001-1250 g from 19% to 13%, 1251-1500 g from 12% to 2% and 1551-2250 g from 3% to 0.2% (P < .05). Proportionately, severe intraventricular hemorrhage (grades 3 +/- intraparenchymal hemorrhage) declined from 70% of all intraventricular hemorrhages in 1986 to 23% in 1995 (P < .005). Overall mortality declined by 65% between 1986 and 1995 (P < .001), whereas mortality associated with intraventricular hemorrhage declined by 30% (P = .34). Despite dramatic declines in intraventricular hemorrhage rates, 21% of infants weighing less than 1000 g and 12% of those weighing less than 1500 g at birth were affected in 1995.

The electroencephalogram (EEG) plays an important role in the evaluation of a child with developmental delay. An EEG is often required to classify seizures in children with developmental delay. Equally important is the role of the EEG in the identification of specific electroclinical syndromes in children who may or may not manifest seizures. Specific electroclinical syndromes include the acquired epileptiform aphasia syndrome, Landau-Kleffner syndrome, and electrical status epilepticus during slow wave sleep. Other clinical situations where the EEG offers diagnostic and prognostic information, such as subacute sclerosing encephalitis, progressive myoclonus epilepsies, Rett syndrome, and Lennox Gastaut syndrome are also discussed.

An 8 year-old girl presented with simple facial motor seizures. Although the electroencephalogram (EEG) demonstrated left hemisphere centrotemporal spikes with features consistent with benign rolandic epilepsy, magnetic resonance imaging (MRI) indicated a left hemisphere focal cortical dysplasia. MRI-assisted EEG dipole analysis of the spikes suggested that the rolandic fissure rather than the focal cortical dysplasia was the origin of the epileptic spike discharge. This noninvasive method may be a useful adjunct in evaluation of some patients with epilepsy and focal superficial cerebral lesions.

Objective: Measure bone mineral density (BMD) in healthy Newfoundland adolescents and determine whether BMD is comparable in geographically diverse adolescent populations., Study Design: Lumbar spine BMD was measured by dual-energy radiograph absorptiometry in 26 healthy adolescents between ages 8 and 20 years. The age and gender of these subjects were used to predict BMD from equations derived from normative BMD data in six geographically diverse populations. The actual BMD value obtained for each subject was then compared with each of the six predicted BMD values for that adolescent using the Wilcoxon signed-ranks test., Results: Actual lumbar spine BMD in Newfoundland adolescents was not significantly different from that predicted by age and gender if they were from California, Finland, France, North Carolina, and Switzerland. Only the prediction based on the Spanish population resulted in a 4% greater BMD than was actually measured in the Newfoundland adolescents., Conclusions: Lumbar spine BMD measurements for most healthy adolescent populations, as in adults, are comparable despite geographic diversity. Thus, generation of institution-specific normative BMD data may not be necessary for most adolescent populations.

Nuchal rigidity and headache are important signs of bacterial meningitis, although, in the absence of fever other etiologies would be considered. An evaluation of a 15-year-old boy with the above features, focal neurological deficits, and two cerebral contrast enhancing ring lesions is discussed.

Recurrent episodes of coma are usually associated with a metabolic disorder. A healthy 9-year-old boy of normal intellect and intact corpus callosum on neuroimaging had recurrent episodes of coma associated with profound spontaneous hypothermia. An evaluation, differential diagnosis and insights into the pathogenesis of this disorder are discussed.

The evaluation of mental retardation is a frequent and challenging problem in pediatric neurology. Often clues obtained on history or by physical examination will help to direct the evaluation in the appropriate channel. This 16-year-old boy had clinical features which suggested the appropriate diagnostic studies.

Thirty-one patients, aged 12.6 +/- 5.6 years, with refractory seizures for 8 +/- 4.3 years, were treated with adjunctive vigabatrin. Twenty-four percent had a > 50% reduction in seizure frequency (95% one-sided confidence interval). Generalized myoclonic, atonic, and tonic clonic and partial, with and without secondary generalization, seizures were all reduced at a mean dose of 70 +/- 38 mg/kg/day. Comparison of vigabatrin therapy duration, for partial and generalized seizure groups, utilizing Kaplan-Meier methodology showed similar survival times. Vigabatrin therapy was ineffective in the four children with tuberous sclerosis. Transient somnolence, ataxia and dizziness were the most frequent side effects. A severe aggressive agitation occurred in three patients, and necessitated discontinuation of vigabatrin in one patient. Vigabatrin was as effective in generalized as in partial seizures in this study. Clinical utility may be limited by unacceptable behavioral side effects in some patients.

It has been suggested that the size of the corpus callosum may have diagnostic significance in cerebral palsy, although this relationship is incompletely defined. Ninety-one patients with cerebral palsy had been studied by magnetic resonance imaging in the 5-year period from 1990 to 1994. Fifty-seven of these 91 patients had a technically appropriate midsagittal magnetic resonance image for quantitative morphometric analysis. The ratio of the area of the corpus callosum to the area of the supratentorial brain was compared to published age- and gender-specific norms. Imaging findings were correlated with clinical history and cause of cerebral palsy. The corpus callosum was of normal size in 43 patients and more than 2 standard deviations below the mean in 14 patients. The causes for cerebral palsy included hypoxic ischemic encephalopathy (32), cerebral dysgenesis (8), and porencephalic strokes (6); the etiology could not be established in 11 patients. The size of the corpus callosum was highly correlated with the cause of cerebral palsy, such that all patients with cerebral dysgenesis had hypoplasia of the corpus callosum (one-sided z test, p < 0.0001). Conversely, the callosum was of normal size in 32 of 38 patients with hypoxic ischemic encephalopathy and porencephalic strokes. The presence of a hypoplastic corpus callosum is highly associated with cerebral dysgenesis as a cause for cerebral palsy.

Midazolam, a potent short-acting benzodiazepine, is a safe and highly effective agent for the control of status epilepticus. Its efficacy in the control of neonatal seizures, however, has not been determined. Six neonates (aged 1-9 days; gestation, 30-41 weeks) developed seizures from a variety of causes. In each case, seizures persisted for > 12 h despite high-dose phenobarbital therapy with or without the addition of phenytoin. Midazolam was then administered by continuous intravenous infusion (0.1-0.4 mg/kg/h) for 1 to 3 days. Within 1 h of initiation of midazolam, seizures were controlled in all six neonates. Electroencephalographic seizures were abolished in four of six neonates; however, two neonates continued to have electrographic seizures (without clinical accompaniment) for a further 12 h. Blood pressure and pulse rate were not changed after the initiation of midazolam, and adverse reactions were not observed in any neonate. Because more than one third of all neonatal seizures are refractory to high-dose phenobarbital and phenytoin, midazolam administered by continuous intravenous infusion may be a valuable adjunctive therapy.

Eight patients with hypertensive encephalopathy from diverse etiologies developed cerebral edema in the vertebrobasilar distribution which resolved after blood pressure was lowered. Parietal occipital edema is a recognized feature of hypertensive encephalopathy. The explanation for this regional pathological variation in hypertensive encephalopathy remains undefined. Some evidence suggests that sympathetic innervation of the anterior cerebral vasculature may be protective, and conversely, the relative lack of sympathetic innervation in the vertebrobasilar vasculature may predispose the parietal occipital region to the development of cerebral edema in hypertensive encephalopathy.

Objective: To determine growth in head circumference from birth to 18 months of age in normal infants with low birth weight., Methods: Healthy, appropriate-for-gestational-age, singleton, white infants weighing less than or equal to 2500 g at birth and with normal development at 18 months of age were included in this study. Serial measurements of head circumference (corrected for gestational age) from 450 eligible infants were compared with reference data for head circumference., Results: Longitudinal measurements of head circumference for infants weighing more than 1000 g at birth were similar to reference data for term infants. Head measurements for infants weighing less than or equal to 1000 g at birth were notably smaller than the measurements in the reference data. A cubic spline curve drawn through the head circumference measurements between birth and age 18 months (corrected for gestational age) for infants weighing less than or equal to 1000 g at birth was significantly (P < .001) below the curve for infants weighing more than 1000 g at birth. At age 18 months, the mean difference in head circumference between the group weighing less than or equal to 1000 g at birth and the weights in the reference data was 1.6 cm (P < .01). (Data were analyzed with Wilcoxon's signed rank test.), Conclusions: These data show that head circumference grids are appropriate for observing head growth in infants with a birth weight more than 1000 g. However, head circumference growth for normal infants with birth weight less than or equal to 1000 g does not "catch up" with that of larger premature infants or term infants.

Multiple cystic lesions in brain parenchyma supplied by the anterior cerebral circulation is a recognized pattern of cerebral injury associated with hypoxic-ischemic encephalopathy in the term infant. This report presents a series of seven infants (gestational age, 39.3 +/- 2.8 weeks; range, 36 to 44 weeks) who developed multicystic encephalomalacia in the distribution of the anterior cerebral circulation after severe neonatal asphyxia. Cerebral imaging and pathologic studies demonstrate relative preservation of the cerebellum, brain stem, and cerebral structures supplied by the vertebrobasilar circulation. Compared to the vertebrobasilar vasculature, the anterior cerebral vessels in the term infant have dense sympathetic innervation. Asphyxia, a potent sympathetic stimulator, may induce vasoconstriction in the anterior circulation and differentially accentuate the effects of hypoxia/ischemia on cerebral tissue.

Approximately 15% of all cerebral arteriovenous malformations (AVMs) present with progressive neurologic deficits, the pathogenic mechanism of which has not been established. One suggestion is that AVMs by expanding over time compress normal surrounding cerebral parenchyma and thereby cause progressive neurologic impairment. Alternatively, a vascular steal results in progressive ischemia of normal cerebral tissue. Because the area occupied by the AVM and the area of observed blood flow reductions in all reported patients have overlapped, delineating the relative contribution of local compression from that of vascular steal has not been possible. We present a 7-month-old girl and a 7-year-old boy with AVMs restricted to the diencephalon who had progressive cognitive impairment and dystrophic cerebral hemispheral calcification (in the 7-month-old girl) indicating diffuse cerebral cortical involvement remote from the AVM. These patients provide evidence for vascular steal, and not local compression, as the primary mechanism underlying a progressive neurologic course associated with some AVMs.

Sepsis occurs frequently in the pediatric intensive care unit and is a significant cause of morbidity and mortality. Multiple organ systems are adversely affected by sepsis. Approximately 70% of adult patients with sepsis have peripheral nervous system dysfunction on electrophysiologic studies, of whom 30% are symptomatic. Neuromuscular dysfunction in children with sepsis is increasingly reported; however, the incidence remains undefined. Flaccid quadriplegia with the inability to wean from ventilatory support despite full cardiopulmonary recovery is the typical presentation. However, lesser degrees of weakness may be demonstrated with careful evaluation. Electrophysiologic studies often demonstrate the presence of axonal polyneuropathies, abnormalities of neuromuscular transmission, or acute myopathies. Identifiable neuromuscular syndromes in children with sepsis include critical illness polyneuropathy, pure motor polyneuropathy, thick-filament myopathy, and necrotizing myopathy. The common underlying pathogenic process in these syndromes appears to be sepsis, which may be accentuated by the administration of steroids or neuromuscular blocking agents. Recovery in strength usually occurs over a period of weeks to months.

Objective: To examine the effect of carbamazepine and valproate monotherapy on bone mineral density in children., Methods: Axial (second, third, and fourth lumbar vertebrae) and appendicular (distal third of radius) bone mineral density was measured by dual-energy x-ray absorptiometry in 27 healthy children and 26 children with uncomplicated idiopathic epilepsy treated with either carbamazepine (n = 13) or valproate (n = 13) for more than 18 months. Control subjects and patients were similar with respect to age, race (all white), and geographic area, and had no dietary restrictions, neurologic impairment, or physical handicaps., Results: Subjects were seizure-free for more than 6 months on a regimen of carbamazepine or valproate therapy, and had mean serum trough levels of 6.88 +/- 2 micrograms/ml and 72.04 +/- 45.6 micrograms/ml, respectively. Dietary calcium intake was similar in control and treated groups. After correction for gender and age, children treated with valproate had a 14% (p = 0.003) and 10% (p = 0.005) reduction in bone mineral density at the axial and appendicular sites, respectively. The reduction in bone mineral density increased with the duration of valproate therapy. Carbamazepine did not significantly reduce bone mineral density., Conclusion: Valproate montherapy, but not carbamazepine therapy, significantly reduces axial and appendicular bone mineral density in children with idiopathic epilepsy and may increase their risk of osteoporotic fractures.

We report the first two children to have the "opsoclonus myoclonus syndrome" after a serologically confirmed acute Epstein-Barr virus infection. Although opsoclonus was absent in one patient, both patients had all other features typical of this syndrome. Patients without opsoclonus have been described as having an isolated postinfectious myoclonus syndrome but probably lie within the spectrum of opsoclonus myoclonus syndrome. The prognosis for the opsoclonus myoclonus syndrome in children with Epstein-Barr virus infection and without evidence for a neuroblastoma appears to be better than in those patients where a cause cannot be identified.

We report our experience with add-on clobazam therapy over a 5-year period in 63 children with refractory epilepsy. The mean duration of epilepsy was 6.7 years. Children were followed for 15 to 64 months. Of 63 children, 57 were developmentally delayed, and 54 had a symptomatic/cryptogenic epilepsy. Forty-one percent became either seizure free or had a greater than 90% reduction in seizure frequency. Seizure frequency was reduced 50% to 90% in another 24%. The average daily dose of clobazam was 0.8 mg/kg. Thirty-five percent had the medication withdrawn for persistent or unacceptable side effects or the development of tolerance (seven patients). Side effects included severe aggressive outbursts, hyperactivity, insomnia, and depression with suicidal ideation. Clobazam is a useful add-on medication for 65% of children with epilepsy. Clinical utility may be limited by behavioral side effects in some patients.

Four children with prolonged dependency on a ventilator were found to have reversible quadriparesis, muscle wasting, and hyporeflexia after 8 to 20 days of assisted ventilation for life-threatening sepsis or respiratory failure. Critical illness neuromuscular disease, which was recently recognized as a distinct clinical syndrome in adults, may also be manifested in children by prolonged ventilatory dependency.

Acute confusional migraine in children and transient global amnesia in adults share a number of similar clinical manifestations. Acute confusional migraine in 6 children (mean age: 11.7 years; range: 7.5-17 years) was characterized by transient episodes of amnesia and acute confusion lasting 1-12 hours. Episodes were preceded by headache and vomiting in 4 patients. In 2 patients acute confusional migraine was the initial symptom. A history of preceding trivial head injury was reported in 3 patients and migraine in 4. Urine and serum drug screens were negative. Cerebral imaging studies and interictal electroencephalograms were normal. Ictal electroencephalograms in 3 patients revealed diffuse or bioccipital delta wave slowing. Recurrent episodes of acute confusional migraine occurred in 2 children during 1-3 years of follow-up. The clinical manifestations of acute confusional migraine in this series of children are similar to those reported in transient global amnesia. The similarity of the clinical manifestations of acute confusional migraine in children and transient global amnesia in adults suggests that these disorders may share a common pathophysiology.

A significant portion of patients with neurodevelopmental abnormalities (mental retardation, learning disabilities, and so forth) have no definable cause for these problems. Mounting evidence suggests a substantial number of these idiopathic conditions have subtle abnormalities of brain development (cerebral dysgenesis) as the inherent pathophysiologic event. In this article the authors summarize normal and abnormal brain development, the diagnostic approach to idiopathic neurodevelopmental anomalies, and the new molecular genetic insights into the underlying causes of brain malformations.

In young children, differentiating seizures from nonepileptic "spells" by history alone can be difficult, even for the specialist. Nonepileptic spells may be psychogenic (rare in the young child) or physiologic in origin. Physiologic spells misidentified as epileptic may be treated with antiepileptic medication where none is needed. Recording spells on video provides a potentially valuable supplement to the clinical history in arriving at a correct diagnosis. In practice, however, most home-video recordings prove difficult to interpret. Simple instructions to parents on the manner in which spells should be recorded will greatly increase the usefulness of home-video recordings. A systemic analysis of precipitating factors and the evolution and resolution of the spell will very often exclude seizures. The widespread availability of home-video recordings provides the pediatrician with an opportunity to visually examine a child's spells, often avoiding unnecessary investigations and referrals and allowing the physician to more confidently offer reassurance to the parents.