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A section of 11 abstracts on dermatology, ophthalmology, surgery, neurology, general psychiatry, internal medicine, head and neck surgery, pediatrics and adolescent medicine, and facial plastic surgery are presented. Abstracts include "Indoor Tanning Attitudes and Practices of US Dermatologists Compared With Other Medical Specialists," "Protracted Ictal Confusion in Elderly Patients," and "Adoption of Patient-Centered Care Practices by Physicians: Results From a National Survey."

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.)

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.

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.

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.

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.