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R R Clancy

Publications and source records attributed to R R Clancy.

At least 37 records · Page 2Linked to original sources
PubMed1995

Serum prolactin in neonates with seizures.

We studied serum prolactin (PRL) in 28 newborn infants with acute encephalopathy. Six patients had electrographically confirmed seizures. Twenty-two patients comprised the nonictal group. In the seizure group, PRL was determined at the first onset of the seizure (baseline) and at 15 and 30 min postictal. In the nonseizure group, PRL was determined at the end of the EEG and 15 min later. EEGs were visually analyzed for the presence of seizures and background abnormality (normal or mildly, moderately, or markedly abnormal). Etiologic diagnoses included congenital heart disease (12), hypoxic-ischemic encephalopathy (4), sepsis (4), respiratory distress syndrome (5) meconium aspiration (1), and metabolic disease (2). Serum PRL was significantly higher (p < 0.05) at baseline and 15 min postictally in the patients with seizures than in the nonictal group. However, PRL levels 15 and 30 min postictally were not statistically different from baseline values. Baseline PRL correlated significantly (p < 0.001) with EEG background abnormality in both groups; therefore, patients with the most abnormal EEG backgrounds had higher levels of PRL than those with a relatively normal EEG background. We conclude that newborns with EEG-confirmed seizures, particularly if seizures are not associated with clinical signs, have high baseline serum PRL levels that do not increase significantly in the immediate postictal period. Serum PRL levels correlate with the severity of the brain insult as evaluated by EEG background. Further studies are needed to enhance our understanding of the dynamics of PRL secretion in newborns with seizures and acute encephalopathy.

Acute Disease↗
PubMed1994

The pharmacokinetics of injectable allopurinol in newborns with the hypoplastic left heart syndrome.

OBJECTIVE: The purpose of this investigation was to determine the pharmacokinetic disposition of intravenous allopurinol and its metabolite oxypurinol in neonates with the hypoplastic left heart syndrome (HLHS) and to evaluate the subsequent degree of xanthine oxidase inhibition using serum uric acid as a marker. METHODS: Pharmacokinetic data were evaluated in 12 stable preoperative neonates with HLHS after a single intravenous allopurinol administration of 5 mg/kg or 10 mg/kg. Pharmacokinetic parameters were determined for elimination half-life, clearance, volume of distribution, and mean residence time. Xanthine oxidase inhibition, measured by serum uric acid reduction, was also measured. RESULTS: Pharmacokinetic parameters revealed no statistically significant differences between a 5-mg/kg and 10-mg/kg dose of intravenous allopurinol on elimination half-life, clearance, volume of distribution, and mean residence time. Mean serum uric acid levels were significantly reduced from baseline by 39.99 and 42.94%, respectively, in the 5- and 10-mg/kg treatment groups. DISCUSSION: The enzyme xanthine oxidase plays a key biochemical role in the generation of toxic oxygen-derived free radicals during ischemia-reperfusion conditions. Allopurinol and its active metabolite oxypurinol inhibit xanthine oxidase, and significantly reduce the conversion of hypoxanthine to xanthine and xanthine to uric acid. Cell injury may be caused by toxic oxygen free radicals produced by ischemia-reperfusion injury such as could occur during the repair of HLHS under hypothermic total circulatory arrest. We hypothesize that allopurinol may provide protection from cellular injury in this clinical context.

Allopurinol↗
PubMed1992

Electroencephalographic and behavioral-state studies in infants of cocaine-addicted mothers.

OBJECTIVE: To evaluate cerebral cortical function with electroencephalography in infants of cocaine-addicted mothers. DESIGN: Patient series. SETTING: The Children's Hospital of Philadelphia (Pa). PARTICIPANTS: Thirty-five consecutive infants of cocaine-addicted mothers hospitalized for a comprehensive health assessment and 51 healthy, age-matched infants studied with electroencephalography and respiratory thermistor because they were siblings of sudden infant death victims (comparison group). INTERVENTIONS: None. MEASUREMENTS/MAIN RESULTS: Behavioral states during spontaneous daytime sleep were classified as active sleep or quiet sleep; quiet sleep was further characterized as immature, tracé alternant sleep or mature, continuous, slow wave sleep. No episodes of ictal apnea or nonictal apnea were recorded in infants of cocaine-addicted mothers; nonictal apnea was observed in one control patient. No electrographic seizures were recorded. There were no significant differences between the proportions of infants exposed to cocaine in utero and that of controls who displayed excessive sharp electroencephalographic transients, background abnormalities, immaturity, and hypermaturity. Electroclinical sleep discordance was present in 5.7% of infants of cocaine-addicted mothers vs 0% of controls. Cocaine-exposed infants displayed mature, continuous, slow wave sleep below 45 weeks of conceptional age in a significantly higher percentage than those in the comparison group. CONCLUSIONS: Although frank electroencephalographic abnormalities were infrequent in infants whose mothers were addicted to cocaine, they differed significantly in their younger age of onset of continuous, slow wave sleep. Our findings provide continued reason for concern that infants of cocaine-addicted mothers may suffer subtle adverse neurologic, cognitive, or behavioral effects later in life. The longitudinal assessment of sleep disturbance and its relation to later development might permit tracking of the long-term effects of prenatal exposure to cocaine.

Child↗
PubMed1992

Adequacy of routine EEG examinations in neonates with clinically suspected seizures.

This study identified the clinical and electroencephalographic (EEG) characteristics that distinguished neonates with EEG-confirmed seizures from those without, in order to assess the adequacy of routine short-term EEG examinations in neonates with clinically suspected seizures. Two different subgroups of tracings were analyzed: EEGs performed on therapeutically paralyzed (TP+) neonates and EEGs performed on non-therapeutically paralyzed (TP-) neonates. The rate of electrographic seizures, abnormal EEG background activity, and excessive sharp EEG transients (SETs) was significantly more common in the tracings performed on TP- neonates. In lethargic/comatose TP- neonates with clinically suspected seizures and abnormal EEG background activity, the rate of EEGs with excessive SETs (implying a "lowered seizure threshold") occurred equally in tracings with or without documented electrographic seizures. Consequently, we suspect that routine EEGs may be inadequate to electrographically confirm suspected seizures in some TP- neonates due to a large sampling error. In contrast, routine 40-minute EEGs are probably adequate to seek evidence of electrographic seizure activity in TP+ neonates because their seizure rate is low and most do not display background abnormalities or excessive SETs.

Cerebral Cortex↗
PubMed1991

EEG changes during recovery from acute severe neonatal citrullinemia.

We report our observations of serial clinical and EEG examinations in 3 neonates during recovery from acute severe encephalopathy due to citrullinemia. Their electroclinical picture closely resembles the clinical stages of experimental models of hyperammonemia in monkeys. The length of the EEG interburst interval, a quantitative measure of EEG background abnormality, correlated with elevated serum levels of ammonia and suggests that hyperammonemia itself is a key figure in the genesis of encephalopathy in this condition. Finally, the manner in which the EEG normalizes during recovery from hyperammonemia in this setting suggests that burst-suppression resembles an exaggerated regression to the discontinuity of the very premature infant.

Ammonia↗
PubMed1991

Significance of positive temporal sharp waves in the neonatal electroencephalogram.

We reviewed our computerized neonatal EEG database for records judged to display excessive positive temporal sharp waves (PTS) to determine their electroclinical associations and significance. Typical infants with excessive PTS were: (1) mature, with a mean conceptional age of 41.2 weeks, and (2) neurologically ill, judged by their high rate of associated EEG background abnormality (37 of 46; 80%) and clinical signs of encephalopathy (19 of 29; 66%). In comparison, healthy age-matched control infants never had excessive PTS. We consider an excess of PTS to be pathologic since they arise out of an abnormal EEG background in children exposed to potentially serious central nervous system illnesses and are associated with a high incidence of cerebral structural abnormalities (16 of 25; 64%). PTS may be comparable to the positive rolandic or vertex sharp waves in premature infants with periventricular injury of the deep white matter.

Brain Diseases↗
PubMed1991

Lissencephaly-pachygyria associated with congenital cytomegalovirus infection.

We report the presence of major cerebral migrational defects in five severely, multiply handicapped children with congenital cytomegalovirus (CMV) infection. These patients had both computed tomographic (CT) scan and magnetic resonance imaging (MRI) evidence of marked migrational central nervous system defects consistent anatomically with the spectrum of lissencephaly-pachygyria, a disorder commonly idiopathic or associated with chromosomal abnormalities or with unknown early gestational insults. Neuroradiologic features included broad, flat gyri, shallow sulci, incomplete opercularization, ventriculomegaly, periventricular calcifications, and white-matter hypodensity on CT scans or increased signal intensity on long-TR MRI scans. Evidence for congenital CMV infection included prenatal onset of microcephaly, periventricular calcifications, neonatal jaundice, hepatomegaly, elevated CMV-specific immunoglobulin M, or viral isolation from urine. Previous reports of the neurologic sequelae of CMV have emphasized varying degrees of psychomotor retardation, cerebral palsy and epilepsy due to polymicrogyria, periventricular calcification, microcephaly, or rarely, hydrocephalus. Our patients appear to represent extremely severe examples of the effects of CMV on neurologic growth, maturation, and development. Recognition of these severe migrational abnormalities was improved by use of MRI, a technique that affords superior definition of the nature and extent of gyral and white-matter abnormalities. We suggest that these abnormalities may be more common than has previously been recognized.

Atrophy↗
PubMed1991

Neurologic outcome after electroencephalographically proven neonatal seizures.

Infants in whom neonatal seizures were confirmed by randomly recorded ictal electroencephalographic (EEG) tracings were retrospectively examined to determine their global neurologic outcome and the specific frequency of epilepsy, development delay, and cerebral palsy. Perinatal and postnatal clinical and EEG variables were also examined for their relevance to the neurologic outcome. Forty infants with EEG documented seizures of diverse etiologies were studied. The 27 survivors were followed up at a mean of 31 months. The outcome was unfavorable in 70%. The rate of epilepsy was 56%, of developmental delay 67%, and of cerebral palsy 63%. The etiology of seizures was an important factor influencing the outcome. Other clinical factors that showed a significant relationship with global or specific aspects of the neurologic outcome included the age at the onset of seizures, birth weight, and neurologic examination results. The EEG parameters that significantly predicted the neurologic outcome were interictal EEG background, increased seizure frequency, and decreased seizure duration.

Asphyxia↗
PubMed1990

Congenital brain anomalies associated with the hypoplastic left heart syndrome.

This study details the type, frequency, and clinical presentation of developmental brain anomalies in 41 infants with the hypoplastic left heart syndrome encountered during a 52-month interval. Overall, 29% of the infants had either a major or minor central nervous system abnormality. Overt central nervous system malformations, including 3 cases of agenesis of the corpus callosum and 1 case of holoprosencephaly, were seen in 4 infants (10%). Micrencephaly (brain weight at autopsy more than 2 SDs below the mean for age) was found in 27% of the infants. An immature cortical mantle was seen in 21% of the study group. Seven infants (17%) had specific recognizable patterns of malformation. The absence of dysmorphic physical features did not preclude overt or subtle central nervous system malformations. Conversely, the presence of dysmorphic features did not reliably indicate an underlying brain anomaly. Infants who had hypoplastic left heart syndrome as one of multiple nonneurologic malformations were more likely to have micrencephaly than those infants with hypoplastic left heart syndrome as an isolated abnormality. Occurrence of developmental neuropathology was elevated in those infants with hypoplastic left heart syndrome who did not have a recognizable pattern of malformation but who were small for gestational age, microcephalic, or had ocular abnormalities. Infants with hypoplastic left heart syndrome deserve careful genetic, opthalmologic, and neurologic evaluations, imaging of their intracranial anatomy, and long-term neurologic follow-up.

Abnormalities, Multiple↗
PubMed1990

Acquired neuropathologic lesions associated with the hypoplastic left heart syndrome.

This study details the type, frequency, clinical presentation, and etiologic associations of acquired brain lesions in 40 infants with the hypoplastic left heart syndrome encountered during a 52-month interval. Detailed postmortem neuropathologic examinations showed that 55% of the infants were free of acquired brain lesions. However, the other 45% had combinations of hypoxic-ischemic lesions and intracranial hemorrhage. Central nervous system perfusion and glucose-oxygen delivery appeared to be important factors in the occurrence of hypoxic-ischemic lesions or intracranial hemorrhage, whereas acidosis and hypercarbia were not. Cerebral necrosis may be a predisposing factor for a major intracranial hemorrhage. A duration of cardiopulmonary bypass with hypothermic total circulatory arrest longer than 40 minutes was associated with a higher incidence of acquired neuropathology. These results indicate that the majority of infants with hypoplastic left heart syndrome are free of acquired neuropathology and suggest practical ways to reduce the risks in the others.

Abnormalities, Multiple↗
PubMed1989

Hypoxic-ischemic spinal cord injury following perinatal asphyxia.

The role of spinal cord injury in the pathogenesis of abnormal motor signs (depressed tone and reflexes) following severe perinatal hypoxia-ischemia was prospectively evaluated by clinical, electrophysiological, and neuropathological examinations in 18 asphyxiated neonates. All infants had an abnormal mental status (lethargy or coma), and seizures were present in 12. Neuromuscular examinations revealed hypotonia or flaccidity and hyporeflexia or areflexia in all infants. Neuropathological examinations of the cerebrum and spinal cord were conducted in the 12 neonates who expired. Cerebral pathological findings included cortical neuronal necrosis in 10 of 12 and subcortical white matter injury in 5 of 12. All infants with coma or seizures displayed diffuse cortical injury, but no injury conformed to a parasagittal "watershed" distribution. Spinal cord gray matter displayed prominent ischemic necrosis in 5 patients who were typically flaccid and areflexic. Electromyographic examinations of all 6 survivors were abnormal, consistent with recent injury to the lower motor neuron above the level of the dorsal root ganglion. We conclude that ischemic injury to anterior horn cells within spinal cord gray matter is relatively common among hypotonic-hyporeflexic neonates following severe perinatal hypoxia-ischemia. Although the acute neurological syndrome of neonatal asphyxia is often overshadowed by prominent cerebral signs such as coma and seizures, the motor abnormalities may be partially attributed to concurrent spinal cord injury.

Asphyxia Neonatorum↗
PubMed1989

Serial EEGs in normal and abnormal infants with birth weights less than 1200 grams--a prospective study with long term follow-up.

Serial EEGs were recorded during the postnatal period from 62 infants with birth weights less than or equal to 1200 gms. Neurological examinations were performed in proximity to the EEG and each infant had at least one imaging study of the brain in the immediate postnatal period. All infants were examined at 2-3 years age. Neurological sequelae were seen in all infants with markedly abnormal neonatal EEGs and in the majority of those with persistently moderately abnormal tracings. A particularly unique EEG abnormality consisting of an arrest of maturation of cerebral electrical activity was seen in infants with bronchopulmonary dysplasia who suffered neurological sequelae. A persistently asymmetric EEG background was recorded in infants with hemispheric pathology who were found to have hemisyndromes at long term follow-up. Serial EEGs were better predictors of long term outcome than imaging studies and the neurological examination.

Brain↗
PubMed1989

Interictal sharp EEG transients in neonatal seizures.

This study describes the differences between several quantifiable variables that characterize interictal sharp EEG transients (SETS) recorded from neurologically ill neonates with proven electrographic seizures and a comparison group of apparently neurologically well babies with no known seizures. The abundance (number of sharp EEG transients per ten minutes), waveform morphology, repetitive behavior, and spatial distribution of SETS provide interpretive guidelines that help discriminate between these two patient populations.

Electroencephalography↗
PubMed1987

New anticonvulsants in pediatrics: carbamazepine and valproate.

The majority of patients with epilepsy have their first seizure during childhood and are first evaluated and diagnosed by their pediatrician. For many patients the medication selected by the pediatrician will be taken for an extended time period, perhaps even for a lifetime. The first job of the pediatrician is to be sure that the patient's recurrent attacks represent genuine epilepsy and not some other paroxysmal medical disorder such as migraine or cardiac arrhythmias. Epileptic seizures are then classified by a careful clinical description of the attacks in conjunction with the results of the physical and EEG examinations. Based on all of the information at hand, the clinician chooses the drug that is most likely to reduce or eliminate further seizures without exposing the child to unnecessary medical risk or behavioral-cognitive adverse effects. In properly selected patients, both carbamazepine and valproate are safe, physically well tolerated, and less likely to provoke chronic mental side effects than the pediatrician's "traditional" choices: phenobarbital or phenytoin. Although carbamazepine and valproate have been widely acclaimed by neurologists and epileptologists, practicing pediatricians have heretofore been less likely to initiate treatment with these drugs. Yet pediatricians have something of priceless value to offer the child with epilepsy: seizure control and a clear mind. The information in this monograph should assist the practicing pediatrician in the rational choice, initiation, and follow-up of treatment with these two excellent anticonvulsants.

Adolescent↗
PubMed1987

Midline foci of epileptiform activity in children and neonates.

We report the clinical and electroencephalographic (EEG) correlates of focal potentially epileptogenic discharge arising from midline sagittal vertices (Fz, Cz, Pz) in 21 children prospectively identified from among 7,051 consecutive EEGs recorded during a 27-month period. The patients range in age from neonates to 13 years. EEGs were obtained during evaluations for solitary or recurrent seizures (17/21), attention deficit disorder (2/21), psychomotor retardation (1/21), and headache (1/21). Clinical seizure types were diverse and included simple partial (5/17), complex partial (2/17), generalized tonic-clonic (4/17), mixed (2/17), and neonatal (4/17). The majority (13/21) of patients had an identifiable etiology for their disorder; CT scans verified mass lesions in two patients. Midline epileptogenic foci were present during wakefulness in 14 of 17 older children and restricted to sleep in the others. Sleep states were indeterminate in the four neonates. Midline foci were exquisitely confined to Fz, Cz, and/or Pz in 6 of 17 older children and would have been entirely missed by a recording montage that did not include vertex electrodes. In five other children, midline foci spread preferentially to the adjacent central-parietal regions and closely resembled the appearance of benign rolandic foci in the longitudinal EEG montages, a potentially serious cause of EEG misinterpretation in view of the high incidence of neuropathology in this patient group.

Adolescent↗
PubMed1985

Neurologic manifestations of the organoid nevus syndrome.

Prominent neurologic abnormalities were observed in six patients with epidermal or linear sebaceous nevi (organoid nevi). These cases were remarkable for unilateral facial nevi, cognitive impairment, seizures, and focal or lateralized epileptic EEG abnormalities. Additional manifestations included the onset of seizures in the neonatal period, unilateral hypsarrhythmia or Lennox-Gastaut EEG pattern, hemiparesis, asymmetric macrocephaly, and somatic growth disturbances. The full expression of this disorder was not apparent at birth, but emerged gradually during infancy. The neurologic abnormalities in these patients were attributed to unilateral or asymmetric malformations of the CNS as demonstrated by computed tomography. A lateralized disorder of neuroectodermal proliferation, differentiation, and migration could account for both the cutaneous and neurologic abnormalities in this disorder. The striking clinical similarities in these patients suggest a close link between epidermal and linear sebaceous nevi.

Abnormalities, Multiple↗