Neuropsychological and behavioral effects of postnatal dexamethasone in extremely low birth weight preterm children at early school age.

OBJECTIVE: To study postnatal dexamethasone treatment effects on cognitive, neuropsychological and behavioral functioning at early school age in preterm children. STUDY DESIGN: We recruited 222 children born between 1998 and 2003: 114 extremely low birth weight (<1000 g; 60 dexamethasone-treated; 54 untreated) and 108 term-born. Data were analyzed using multivariate methods. RESULT: Preterm performed below term-born on all measures. Dexamethasone-treated performed below dexamethasone-untreated in immediate visual memory, visual-motor integration, mathematical skill and motor dexterity. However, stepwise regression indicated that medical and sociodemographic factors other than dexamethasone contributed to preterm group differences. CONCLUSION: Dexamethasone alone does not explain neurocognitive impairment in preterm children. Medical and sociodemographic factors (illness severity, male gender and parental education) are influential. Prospective longitudinal neuropsychological and behavioral study from preschool to school age that considers medical and sociodemographic variables will best address effects of dexamethasone exposure.

Neuropsychological functioning in early hydrocephalus: review from a developmental perspective.

Children with hydrocephalus have deficits in several neuropsychological domains. The most notable are motor, visuoperceptual, and visuomotor function. These deficits are multiply determined and depend on the etiology and severity of the hydrocephalus to a large extent. Corpus callosum abnormalities resulting from stretching of callosal fibers and other cortical white matter tracts are implicated as contributory to these deficits. Enlarged ventricles and associated compression of posterior cortical areas also correlate with cognitive impairment. Distinguishing which cognitive domain negatively impacts on the child's functioning and which domains influence behavior in isolation or in combination has been the subject of numerous studies. Developmentally, we know little about the emergence of neuropsychological functioning in children with hydrocephalus. Study of the effects of hydrocephalus at different stages of development is useful to clinicians and researchers interested in the impact of diffuse neurophysiological damage on cognition in the developing brain. The medical and neuropsychological literature have begun to inform about these effects. The core deficits in hydrocephalus have yet to be explicated and a focus on investigations that answer these questions is required. This review summarizes the current knowledge about neurocognitive sequelae of hydrocephalus.

A novel approach to the determination and characterization of HIV dementia.

BACKGROUND: Neuropsychological studies of the pattern and extent of cognitive impairment in HIV-infected patients have mostly used deviations from control values and/or cut-off scores as criteria for classification of dementia. There is, however, no agreement as to how to define impairment, and classification is imprecise. METHOD: The current study used a dementia classification matrix, developed with a step-wise linear discriminant analysis of neuropsychological data from patients with primary neurodegenerative dementias, to classify symptomatic HIV patients as demented or non-demented, and further to differentiate cortical and subcortical dementia patterns. Thirty-two male and 2 female patients (mean age 39 +/- 2) with symptomatic HIV disease (mean absolute CD4 count 195 +/- 41) participated in the study. RESULTS: Thirty-five per cent of patients were classified as demented. Of these, 83% showed a subcortical pattern and 17% a cortical profile of deficits. Significant differences between patients classified as subcortically demented and those categorized as normal on neuropsychological measures associated with subcortical integrity further validated the classification. Measures of psychiatric status between subgroups were similar. CONCLUSION: Since certain treatments may delay or reverse cognitive deficits, the use of an objective classification method based on discriminant analysis may help to identify patients who may benefit from therapy.

Normal pressure hydrocephalus in patients with myelomeningocele.

Although the syndrome of normal pressure hydrocephalus (NPH) was described in the adult as early as 1964, it has only recently been recognized in the child. In this preliminary report, eight myelomeningocele patients with presumed NPH were evaluated before and after ventricular shunting procedures. Cranial computed tomography and serial psychological testing have proved to be particularly valuable both in the pre-operative and post-operative assessment of these patients and have the distinct advantage of being simple, non-invasive diagnostic measures. Continuous intra-ventricular pressure monitoring has shown what promises to be characteristic elevated pressure plateaux imposed on normal baseline cerebrospinal fluid (CSF) pressures in so-called NPH but is a more difficult clinical procedure, necessarily associated with potential complications. Although decreasing response to growth-stimulating hormone can be demonstrated in patients with long-standing hydrocephalus, this endocrine malfunction cannot be considered an early indicator of intracranial pathology. Single IQ scores are inadequate measures of intellectural function in children with NPH and serial examinations should be carried out. Detailed neuropsychological testing will document performance IQ scores well below verbal IQ scores and will generally show failure of psychomotor development to keep pace with chronological ageing. Initial studies indicate that improved performance scores can be expected within 1 1/2 to 3 months following successful ventricular shunting operations, and that any downward trend in pre-operative test scoring can at least be reversed. Statistically significant improvements in full-scale IQ scores have not been seen, however, before the end of the first post-operative year. Clinically, improved attentiveness and sociability, and decreased spasticity (if present prior to surgery) can be expected following shunting. Over-all, ventriculomegaly, normal CSF pressure, stable head size, and non-progressive neurological symptoms cannot be regarded as sufficient criteria for the diagnosis of an arrested state of hydrocephalus, and should suggest NPH, especially in those children who demonstrate a discrepancy between performance and verbal IQ scores and who fail to exhibit continuing psychomotor development with advancing age.