Biomedical subjects
A Leviton
Publications and source records attributed to A Leviton.
Densely cellular cerebellar tumors in children.
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Methylphenidate therapy for inattentiveness in selected school children.
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The influence of route of delivery and hyaline membranes on the risk of neonatal intracranial hemorrhages.
The relationship of route of delivery and hyaline membranes to eight sites of intracranial hemorrhage was evaluated in 513 autopsied newborn infants. Those delivered by cesarian section appeared to be at less risk for most hemorrhages compared with newborns delivered vaginally. However, the reductions in risk were small and did not achieve nominal levels of statistical significance. Thus, "birth trauma" probably contributes little to the risk of most neonatal intracranial hemorrhages. Newborns who developed hyaline membranes appeared to be at greater risk for most hemorrhages than those who did not, particularly if the infant had been delivered by cesarian section. This was especially marked for subarachnoid and germinal matrix hemorrhage.
Limitations of autopsy data in relating neonatal intracranial hemorrhage to buffer therapy.
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Histologic features and observational variation in cerebellar gliomas in children.
Variation existed in the recognition of histologic features commonly used in the evaluation of cerebellar gliomas of childhood. Some histologic features (e.g., perivascular pseudorosettes, leptomeningeal deposits, and calcification) were more reliably observed than were others (e.g., Rosenthal fibers, cell density, and hypervascularity). Knowledge of which features tend to have greater observational variation may lead to improved definitions, less reliance of these features in clinical decisions, further studies of the potential sources of the variation, and guidelines for minimizing observational variation.
Cerebellar gliomas in children.
We studied the relationship of histologic features to survival in a population of 132 children with cerebellar gliomas (excluding medulloblastomas). These children had their initial tumor operation at The Children's Hospital Medical Center of Boston between 1l927 and 1968. A classification system that accentuates differences in survival was derived on the basis of clustering of histologic features and survival. This division was supported by the existence of differentially distributed symptoms and signs and by differences in resectability. The two major subgroups of cerebellar gliomas had different patterns of clinical characteristics. Cerebellar glioma A had any of the four histologic features of microcyst, leptomeningeal deposit, Rosenthal fiber, or focus of oligodendroglia; children with glioma A had a 10-year survival rate of 94%. Glioma B, encompassing the histologic features of perivascular pseudorosette, high cell density, necrosis, mitosis, and calcification, was clearly defined but histologically less uniform; children with glioma B had a 10-year survival rate of 29%. These two groups accounted for 90% of the cerebellar gliomas in childhood.
Secular trends of cerebellar gliomas in children.
Temporal changes in the histologic composition of cerebellar gliomas were examined in a population of 132 children operated on between 1927 and 1968 at The Children's Hospital Medical Center of Boston. Linear trends with time were examined for clinical features, histologic features, and tumor types. We found evidence of an increasing occurrence of glioma A and its associated features during the 41-year study period. This tumor type is associated with a good prognosis and is histologically well defined. Glioma B, a tumor type associated with a poor prognosis, was relatively stable with respect to time and, therefore, differed markedly from glioma A. Foci of oligodendroglia, a glioma A feature, clustered by year of surgery within a relatively short time span. This feature had a survival rate and a male sex proportion quite different from those of the other histologic features investigated.
Risk factors of delayed myelination in the newborn.
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Letter: Birth order and left-handedness.
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Endotoxin leucoencephalopathy in the telencephalon of the newborn kitten.
Prolonged exposure of the neonatal kitten to a lipopolysaccharide results in a telencephalic leucoencephalopathy characterized by astrogliosis and necrosis. The visceral organs of neonatal kittens and the telencephalon of mature cats are relatively resistent to the adverse effects of this lipopolysaccharide.
Multivariate analysis of risk of perinatal telencephalic leucoencephalopathy.
The hospital and autopsy records of 40 infants who died with perinatal telencephalic leucoencephalopathy (PTL) (hypertrophic astrocytes and amphophilic globules in telencephalic white matter) were compared to those of 76 control infants who had no white matter abnormality. A linear discromination procedure, which takes into account multiple confounding factors, was used to estimate risk ratios. PTL was found more commonly in infants who (a) had bacteria isolated from blood at autopsy, (b) received intravenous glucose and water for more than one day, or (c) received kanamycin or streptomycin. Infants were at reduced risk if they received penicillin, atropine, mercurhydrin or a transfusion of whole blood. It is hypothesized that endotoxin from bacteremia adversely affects developing white matter and that the other risk factors of PTL are markers of, or contributors to, increased risk of gram negative infection. No evidence was found for antibiotic-endotoxin interaction. The factors that are associated with reduced risk of PTL may be markers of, or contributors to reduced risk of gram negative infection.
Reaction times and Digit Symbol Test scores of girls identified as daydreamers by their teachers.
Reaction times and Digit Symbol scores of 14 9-yr.-old girls identified as "daydreamers" by their teachers were compared with those of 14 9-yr.-old girls not so identified. Daydreamers tended to have longer mean reaction times under all test conditions but the differences were small. The daydreamers completed significantly less of the Digit Symbol test than did the non daydreamers and also recalled significantly fewer symbols. The daydreamers had significantly larger variances for three of the four measures of outcome of the Digit Symbol test. These data support the hypothesis that girls identified as daydreamers on a questionnaire completed by their teachers did less well on certain tests of attention than girls not so identified.
Cesarian section and the risk of neonatal intracranial hemorrhage.
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"Headache rounds": post carotid-endarterectomy "hemicrania".
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Severe headache after carotid endarterectomy.
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Contraction stress test for antepartum fetal evaluation.
The contraction stress test (CST) was used to attempt determination of fetal reserve prior to labor by evaluating the response of the fetal heart rate to spontaneous or induced uterine contractions. Testing was performed by using an external fetal heart rate monitor and tocograph. The CST was employed 189 times in 120 high-risk patients who either had hypertensive disorder of pregnancy or had completed at least 42 weeks of gestation. Testing was begun as early as 34 weeks' gestation and repeated at weekly intervals; it was not used in the clinical management of the patient. The maximum number of tests performed on one patient was 8. A negative CST appears to be a most reliable guide to the ability of the fetus to tolerate labor if it ensues within 1 week. A positive test suggests that the fetus is at increased risk, but death is not necessarily imminent. Results of the present study warrant use of the CST in controlled studies to determine its effect in improving perinatal outcome.