Update of the Amiel-Tison neurologic assessment for the term neonate or at 40 weeks corrected age.

Amiel-Tison neurologic assessment at term has recently been updated for clinical application. Experience in this field, in addition to a better understanding of pathophysiologic characteristics of the immature brain, has taught us that an increased precision in assessing central nervous system function in the neonate is compatible with a simplification of the clinical instrument. The complete procedure takes approximately 5 minutes. A simple 0, 1, and 2 scoring system is proposed. Because this coding system is not quantitative, any computation of quotient or total score is inappropriate. Rather, a final synthesis based on clusters of signs and symptoms is advisable. A distinct final synthesis is proposed for term newborn infants in the first week of life and for preterm neonates at approximately 40 weeks of age corrected. Clinical profiles emerging from repeated assessments in the term newborn and early clinical findings indicating a brain damage of prenatal origin are described. Interrater reliability has been proved to be more than satisfactory. Such an assessment is useful for any newborn infant in maternity wards or for any preterm infant approximately 40 weeks of age, with or without abnormal imaging findings.

Fetal adaptation to stress: Part II. Evolutionary aspects; stress-induced hippocampal damage; long-term effects on behavior; consequences on adult health.

Humans share adaptative capacities to stress with other species, as demonstrated on amphibians: the physiological response to experimental water volume and food deprivation results in the activation of the endocrine axes that drive metamorphosis, in particular the neuroendocrine stress system. Unfavorable effects may, however, occur, probably due to inappropriate timing and/or duration of stress: recent experiments are converging to show a profound impairment of hippocampal functioning in the offspring of mothers exposed to prenatal stress. Moreover, fetal changes are likely one of the risk factors for a number of diseases in adulthood.

Fetal adaptation to stress. Part I: acceleration of fetal maturation and earlier birth triggered by placental insufficiency in humans.

This review is an attempt to provide an integrative view for the biological changes triggered by fetal stress through a multidisciplinary approach. Acceleration of brain and lung maturation in certain risk pregnancies was first described clinically and confirmed by biochemical, electrophysiological and experimental data. Moreover, new experimental findings suggest that a fetal clock centrally mediated by fetal nutritional status could determine timing of parturition. However, some skepticism persisted about the usefulness of this body of knowledge for obstetrical management in developed countries. The interest concerning this adaptation to intrauterine stress was later renewed from various sources, as developed in Part II.

New scoring system for fetal neurobehavior assessed by three- and four-dimensional sonography.

AIM: To produce a new scoring system for fetal neurobehavior based on prenatal assessment by 3D/4D sonography. We identified severely brain damaged infants and those with optimal neurological findings and compared fetal with neonatal findings. RESULTS: The new scoring system was retrospectively applied in a group of 100 low-risk pregnancies. After delivery, postnatal neurological assessment was performed, and all neonates assessed as normal reached a score between 14 and 20, which we assumed to be a score of optimal neurological development. Subsequently, the same scoring system was applied in the group of 120 high-risk pregnancies in which, based on postnatal neurological findings, three subgroups of newborns were found: normal, mildly or moderately abnormal, and abnormal. Normal neonates had a prenatal score between 14 and 20, mildly or moderately abnormal neonates had a prenatal score of 5-13, whereas those infants who were assigned as neurologically abnormal had a prenatal score from 0-5. CONCLUSION: A new scoring system for the assessment of neurological status for antenatal application is proposed, similar to the neonatal optimality test of Amiel-Tison. This preliminary work may help in detecting fetal brain and neurodevelopmental alterations due to in utero brain impairment.

Neurosonography in the second half of fetal life: a neonatologist's point of view.

This article reviews the interpretation of the fetal motor repertoire in the light of neurophysiology and clinical neurology. The continuity of the maturative process from the fetus to the neonate allows us to speculate on the predictive value of optimal and non-optimal neurological function as observed in the fetus and their morphological consequences. Neonatologists know that early prediction concerning outcome is reliable only at the two ends of the spectrum, e.g., optimal and very abnormal situations. However, in intermediate situations the quality of observations achieved by 3D-4D ultrasonography already allows to demonstrate the prenatal onset of brain damage, based on morphologic and functional signs. Their identification during the second half of pregnancy may serve as a retrospective marker of a prenatal insult.

The Amiel-Tison Neurological Assessment at Term: conceptual and methodological continuity in the course of follow-up.

The Amiel-Tison Neurological Assessment at Term (ATNAT) is part of a set of three different instruments based on a neuro-maturative framework. By sharing a same methodology and a similar scoring system, the use of these three assessments prevents any rupture in the course of high risk children follow-up from 32 weeks post-conception to 6 years of age. The ATNAT which takes 5 minutes to administer may be used in clinical setting as well as in research. Clustering of severe to mild neuro-cranial signs in the neonatal period permits identification of children who could benefit from early intervention.

Macropremies: underprivileged newborns.

The focus of neonatal intensive care has been on very low birthweight infants, who comprise only 1.4% of neonates. Too little attention is paid to moderately preterm infants that we call macropremies or moderately low birthweight infants (MLBW, with birthweights 1500-2500 grams). Admitting over half MLBW infants to normal nurseries presumes that they have few needs and an excellent prognosis similar to fullterm newborns. It does not take into account the macropremie's vulnerability to complications of prematurity due to immature organ systems. Obstetricians are increasingly willing to deliver these infants prematurely for signs of fetal distress. As many as 25% of children with cerebral palsy referred to a disability clinic in Paris were MLBW, with hypoxic-ischemic-inflammatory associated disorders in one-third. The majority of MLBW infants who required neonatal intensive care at a tertiary care center in Baltimore had complications of prematurity: 47% had respiratory problems, 20% had feeding intolerance and 9% had hypoglycemia. MLBW infants comprise 5-7% of the neonatal population but account for 14% of neonatal deaths, 18-37% of children with cerebral palsy and 7-12% of children with mental retardation. Increasing the level of neonatal care for the macropremie's transition to extrauterine life would be economically feasible if it prevented as few as 30% of cases of major disability. A change in attitude towards this low risk (but not risk free) group of MLBW infants will both reduce morbidity and improve their health and neurodevelopmental outcome. It includes: 1) Providing an intermediate level of neonatal care for a short duration, with close monitoring and prompt intervention as needed, and 2) Neonatal neurodevelopmental screening to allow focused neurodevelopmental followup of MLBW infants with abnormalities.

Minor neurological signs and developmental performance in high risk children at preschool age.

The aim of this study was to establish correlations between minor neurological findings and developmental performance. A cohort of 72 preschool children was studied (38 females, 34 males; mean age 3 years 8 months, SD 1 year 2 months, range 2 to 5 years) who were considered to be at high risk due to placental insufficiency. The cohort was divided into four categories of neurological status: (1) minimal cerebral palsy (MCP) with independent walking before age 2 years; (2) Amiel-Tison triad (ATT) including imbalance of passive axial tone, phasic stretch reflex in triceps surae, and cranial signs, particularly on the squamous suture; (3) intermediate with one or two of the three ATT signs; and (4) absence of neurological findings. Six subscales of the Griffiths Mental Developmental Scales assessing locomotion, eye-hand coordination, interpersonal skills, language, performance, and practical reasoning were administered. Significant differences were found according to neurological status in three specific domains of development: coordination (F=2.84, p=0.04), language (F=3.65, p=0.02), and practical reasoning (F=3.62, p=0.02). In addition, significant differences were also found in language (L) and practical reasoning (R) performances according to the side of the abnormal stretch reflex: bilateral stretches (L=87.8; R=75.3) or an isolated right stretch (L=95.3; R=83.6) are more strongly associated with impaired developmental performances than an isolated left stretch (L=101.3; R=88.2) with F=2.94; p=0.04 for language and F=3.00, p=0.04 for practical reasoning. We concluded that a short neurological examination, easily performed by pediatricians and family practitioners, can identify permanent markers of minor brain damage occurring before, during, or soon after birth and so anticipate consequences.

Neurodevelopmental investigations among methylmercury-exposed children in French Guiana.

French Guiana, like its neighbors, suffers from environmental pollution with methylmercury from gold mining activities, and Amerindian communities are particularly affected. A neurological and a neurospsychological evaluation were carried out in children of three Amerindian communities with various levels of pollution: 156 children from the Upper Maroni (high exposure), 69 from Camopi on the Oyapock river (median exposure), and 153 from Awala on the Atlantic coast (low exposure). Exposure to methylmercury was measured by determination of total mercury in the hair of the children and their mothers (geometric mean, 12.7 microg/g in Upper Maroni). No major neurologic signs were observed in the children examined. After adjustment for potential confounders, we found a dose-dependent association between maternal hair mercury level and increased deep tendon reflexes, poorer coordination of the legs, and decreased performance in the Stanford-Binet Copying score, which measures visuospatial organization. In this last test, the frequency of rotation errors was high in the 5-6 years age group and increased with mercury exposure. These associations depended on the sex of child and were stronger among boys. The interpretation of these results is limited mainly by the cross-sectional design of the study. It identifies specific neurological and neuropsychological deficits, in some cases modulated by sex, which are consistent with known targets of mercury neurotoxicity.