Newborn radial nerve palsy: report of four cases and review of published reports.

Four newborns presented with isolated radial nerve palsy during the first 2 days of life. In three, there was a history of failure of progression of labor, which may have resulted in prolonged radial nerve compression. Furthermore, three infants had fat necrosis of the upper arm above the elbow, suggestive of compression of the radial nerve in the region of the spiral groove. Significant recovery of function was evident within 1 month in all four infants. The authors review published reports about the rare condition of isolated radial nerve palsy in the newborn.

Perinatal hypoxic-ischemic thalamic injury: clinical features and neuroimaging.

A common pattern of hypoxic-ischemic cerebral injury in the term newborn involves predominantly cerebral cortex and subcortical white matter. We describe 20 term newborns with moderate or severe acute hypoxic-ischemic encephalopathy who exhibit a different pattern of abnormalities on computed tomography, with evidence of decreased tissue attenuation predominantly in thalami and basal ganglia and relative preservation of cerebral cortex and white matter. Profound, acute hypoxic-ischemic insult (eg, umbilical cord prolapse, uterine rupture, or massive placental abruption) was documented in 16 of 20 infants (80%). Characteristic clinical features during the newborn period included irritability, tonic posturing of limbs, and persistent lower cranial nerve dysfunction, often with prominent tongue fasciculations. This pattern of central injury appears to be highly predictive of poor outcome; 7 newborns (35%) died, and all survivors who had follow-up to 18 months of age (11) had major neurological sequelae (eg, spastic quadriplegia, choreoathetosis, and persistent feeding problems). This pattern of hypoxic-ischemic cerebral injury corresponds closely to experimental animal models of "acute total" perinatal asphyxia.

Intraventricular hemorrhage and posthemorrhagic hydrocephalus. Current and potential future interventions.

Enhanced survival of very premature infants may be regarded as the most striking demonstration of the major improvements in perinatal medicine during the last two decades. This article discusses recent perinatal interventions in the context of the pathogenesis and know risk factors for intraventricular hemorrhage (IVH). In addition, controversies related to the evolution and management of posthemorrhagic hyrdocephalus (PHH) are examined, and current concepts concerning potential brain injury to PHH are reviewed.

Clinical aspects of perinatal hypoxic-ischemic brain injury.

Perinatal hypoxic-ischemic cerebral injury is a significant cause of neurological morbidity and mortality in childhood. It is often difficult to determine the precise timing of such injury. Data from epidemiological and neuropathological studies have identified several maternal and fetal risk factors that seem to be associated with suspected prenatal brain injury. Hypoxic-ischemic cerebral injury that originates earlier in gestation may result in few, if any, clinical abnormalities during the newborn period. Clinical abnormalities may also be difficult to recognize in the premature newborn, and greater reliance must be placed on other adjunctive investigations, eg, neuroimaging. In contrast, term infants who sustain acute, intrapartum hypoxic-ischemic insult of sufficient magnitude to result in long-term sequelae invariably show recognizable encephalopathy during the newborn period. A combination of clinical data and adjunctive investigations during the neonatal period is a powerful predictive tool for long-term outcome.

Neuromuscular disorders in childhood.

The understanding of the molecular genetics of inherited neuromuscular disorders has unfolded rapidly in recent years. Identification of the genetic defects involved has enhanced diagnosis, prognosis, carrier detection, and prenatal diagnosis and has provided a basis for rational treatment strategies. This review provides an update on the most common neuromuscular disorders that present in childhood, eg, spinal muscular atrophy, muscular dystrophies, and myotonic disorders, and includes information on molecular genetics, pathogenesis, natural history, and experimental therapeutic strategies.

Early prediction of the development of microcephaly after hypoxic-ischemic encephalopathy in the full-term newborn.

The development of microcephaly after significant hypoxic-ischemic cerebral injury in the full-term newborn has major prognostic significance. However, the onset of microcephaly in this context may be delayed more than 12 months. OBJECTIVES. To determine whether serial head circumference measurements and decreased rate of head growth in asphyxiated full-term newborns during the first few months of life may predict the development of eventual microcephaly. METHODOLOGY. Serial head circumference measurements at 4, 8, and 18 months of age were obtained in 54 full-term newborns who had acute, hypoxic-ischemic encephalopathy. The rate of head growth was determined on the basis of changes in head circumference ratios which are calculated as follows: actual head circumference/mean head circumference for age x 100%. Head circumference ratios were correlated with severity of newborn encephalopathy and outcome at 18 months. RESULTS. A decrease in head circumference ratios of > 3.1% between birth and 4 months of age was highly predictive of the eventual development of microcephaly before 18 months (sensitivity 90%, specificity 85%). CONCLUSIONS. These data demonstrate that serial head circumference measurements during the first 4 months of life and calculation of decreased rate of head growth in full-term newborns with hypoxic-ischemic encephalopathy may predict microcephaly before its actual occurrence.

Clinical features for prediction of survival in neonatal muscle disease.

Review of 17 newborns with muscle disease demonstrated that clinical features associated with survival beyond 1 year of age included gestational age of at least 35 weeks and requirement of mechanical ventilation for less than 21 days. In contrast, poor outcome was associated with Apgar scores below 5 at 5 min, pulmonary complications, arthrogryposis, or other congenital anomalies. The incidence of decreased fetal movements, polyhydramnios, hypotonia, and assisted delivery was not statistically different between infants who died early and those who survived beyond 1 year of age. Clinical features of newborns with muscle disease may be useful for prediction of outcome, especially when muscle biopsy abnormalities are nonspecific.

Serum sodium concentration and intraventricular hemorrhage in premature infants.

Recent data suggest that early loss of brain tissue water content, ie, decreased extravascular cerebral tissue pressure, may play a role in the pathogenesis of germinal matrix/intraventricular hemorrhage in the premature newborn. This study examines the relationship between the concentration of serum sodium and germinal matrix/intraventricular hemorrhage in 299 premature infants with birth weights of less than 1500 g during the first 4 days of life. Intraventricular hemorrhage developed in 34 (32%) of the 106 infants with maximum serum sodium levels of 145 mmol/L or less and in 54 (28%) of 193 infants whose highest serum sodium levels were greater than 145 mmol/L (chi 2 = 0.37). These data suggest that concentrations of serum sodium greater than 145 mmol/L are not associated with an increased risk of germinal matrix/intraventricular hemorrhage in the premature newborn. Consequently, more liberal administration of fluids to maintain extravascular cerebral tissue pressure is unlikely to reduce the incidence of germinal matrix hemorrhage/intraventricular hemorrhage.

Thalamic hemorrhage with intraventricular hemorrhage in the full-term newborn.

Intraventricular hemorrhage is an uncommon problem in the full-term newborn. In a review of 19 full-term infants with intraventricular hemorrhage diagnosed on computed tomography prior to 1 month of age, thalamic hemorrhage associated with the intraventricular hemorrhage was documented in 12 infants. Thus, thalamic hemorrhage appears to the most common source of intraventricular hemorrhage in this age group, particularly in infants who had uneventful birth histories and in whom clinical abnormalities (signs of increased intracranial pressure, seizures, altered level of consciousness) developed after the first week of life. The majority of these infants had predisposing factors for cerebral venous infarction such as sepsis, cyanotic congenital heart disease, and coagulopathy. The clinical appearance and outcome for infants with thalamic hemorrhage/intraventricular hemorrhage were similar to those in infants with intraventricular hemorrhage originating from other sites, except for an increased incidence of cerebral palsy in infants with thalamic hemorrhage/intraventricular hemorrhage. Definitive diagnosis was made on the basis of characteristic radiologic abnormalities.

Neurosonographic features of Aicardi's syndrome.

Aicardi's syndrome occurs in females and is associated with profound mental retardation, agenesis of the corpus callosum, chorioretinal lacunae, and infantile spasms. We report a distinctive combination of abnormalities which was observed on real-time cranial ultrasound scans of two infants with Aicardi's syndrome. These abnormalities include bilateral prominent cysts in the choroid plexus in conjunction with agenesis of the corpus callosum. Recognition of these radiologic findings may suggest the diagnosis of Aicardi's syndrome in early infancy even prior to the onset of seizures or visualization of chorioretinal lacunae.

Neuromuscular disorders in the newborn.

This article outlines the approach to clinical evaluation of the hypotonic newborn with suspected neuromuscular disease. Specific conditions that affect primarily the anterior horn cell, peripheral nerve, neuromuscular junction, and skeletal muscle are reviewed in the context of current understanding of the development of the motor system. Thus, it may be speculated that the distinction between myopathies and neuronal disorders is somewhat artificial. The difficult ethical decision regarding long-term mechanical ventilation for severe neonatal neuromuscular disease is discussed briefly.

MR imaging of periventricular leukomalacia in childhood.

Eight children with clinical and radiologic abnormalities consistent with periventricular leukomalacia were investigated with MR imaging of the brain that employed both inversion-recovery and T2-weighted spin-echo imaging sequences. The more precise delineation of white and gray matter on inversion-recovery images as compared with CT allows a detailed demonstration of the anatomic features of periventricular leukomalacia; specifically, a reduced quantity of white matter in the periventricular region and centrum semiovale and, in more severe cases, cavitated infarcts that replace the immediate periventricular white matter. The T2-weighted spin-echo and short inversion time inversion-recovery images demonstrated abnormally increased signal in white matter that appeared normal on CT scans and only minimally abnormal on conventional inversion-recovery images. These abnormalities most probably represent white matter gliosis that extends beyond the immediate periventricular regions. MR recognition of cerebral white matter abnormalities associated with periventricular leukomalacia may confirm the clinical suspicion of this diagnosis in children with spastic diplegia or quadriplegia.

Effect of maternal cocaine use on the fetus and newborn: review of the literature.

The recent epidemic of cocaine abuse, especially among young individuals, has caused increasing concern about the potential hazards of prenatal cocaine exposure on the developing fetus and newborn. Although large-scale epidemiologic studies and long-term data are lacking, a review of the literature suggests strongly that the popular belief about the relative safety of cocaine is unfounded and that maternal cocaine abuse during pregnancy may be associated with increased perinatal morbidity and mortality.

Reduced platelet count as a risk factor for intraventricular hemorrhage.

The role of thrombocytopenia as a risk factor for intraventricular hemorrhage in infants of very low birth weight is unclear. This study investigates the relationship between the lowest platelet count and the occurrence of intraventricular hemorrhage in 302 consecutively admitted infants with birth weights under 1500 g. Intraventricular hemorrhage, which occurred in 90 infants (29.8%), was correlated with the lowest platelet count obtained during the first 4 days of life. In 27 infants with intraventricular hemorrhage, the lowest platelet count was less than 100 X 10(9)/L. Statistical analysis of the data demonstrated that reduced platelet count was not associated significantly with intraventricular hemorrhage. Similarly, the severity of intraventricular hemorrhage did not correlate with the lowest platelet count. These data suggest that a reduced platelet count does not play a major role in the pathogenesis of intraventricular hemorrhage in infants of very low birth weight.

Brain swelling in the asphyxiated term newborn: pathogenesis and outcome.

The role of brain swelling following acute hypoxic-ischemic insult in the genesis of brain injury in the term newborn is controversial. Recent experimental animal studies suggest that it may result from prior irreversible cerebral necrosis and therefore represents a consequence as opposed to a cause of major brain injury. In this study, 32 asphyxiated term newborns were studied during the first week of life with serial intracranial pressure measurements. A total of 26 infants had CT scans during the first five days of life. Seven patients had two CT scans within this period. These investigations were correlated with outcome at 18 months of age. Seven infants had increased intracranial pressure (greater than 10 mm Hg) that reached a maximum between 36 and 72 hours of age. Cerebral perfusion pressures remained normal, which makes ongoing ischemic injury unlikely as a cause. The seven patients with increased intracranial pressure had decreased attenuation on CT that was generalized in six infants and patchy in one infant. Of the infants with increased intracranial pressure and severe CT abnormalities, three died and four had severe neurologic sequelae. In seven infants, a second CT scan at three to four days of life demonstrated progression of the decrease in tissue attenuation. Most of the infants with normal intracranial pressure (23/25) had no or had only minor neurologic abnormalities at follow-up. These data suggest that brain swelling is relatively uncommon in the asphyxiated term newborn.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal migration abnormalities can still be diagnosed by computed tomography!

Magnetic resonance imaging is presently the best modality for evaluating gray/white matter anatomy. However, this modality is expensive and not yet readily available in all countries. Most neuronal migration abnormalities can be accurately diagnosed by computed tomography (CT) provided excellent scanning technique is used. Abnormalities of neuronal migration were identified with CT brain scans in 68 children and were categorized as focal heterotopias (11 patients), multifocal heterotopias (19 patients) of diffuse migration disorders (38 patients). The principal indications for imaging were correlated to the radiological features. Neuropathological confirmation of the migration abnormality was obtained in 8 patients. An increased awareness by both clinicians and radiologists together with optimal CT technique are essential for the accurate diagnosis of migration disorders in children.

Selective brainstem injury in an asphyxiated newborn.

We report the clinical, radiological, and neuropathological features of selective brainstem injury in an asphyxiated term infant. Disproportionate injury to thalamus, basal ganglia, and brainstem with relative sparing of cortex and subcortical white matter is observed occasionally after acute total asphyxia. Although this entity has been well documented neuropathologically, the specific computed tomographic findings have not been reported previously to our knowledge, and the clinical correlation is recognized rarely.

Periventricular leukomalacia: radiologic diagnosis.

Fifteen infants and children with clinical evidence of periventricular leukomalacia (i.e., spastic diplegia or quadriplegia and premature birth) were studied. Computed tomography (CT) scans of the brain demonstrated the following characteristic abnormalities: reduction in quantity of periventricular white matter, particularly at the trigone, deep and prominent sulci that abutted the ventricles without interposed white matter, and ventriculomegaly with irregular outline of the lateral ventricles. The location and severity of abnormalities on CT scans correlated well with the neurologic abnormalities observed at follow-up and the known anatomic location of periventricular leukomalacia. These observations demonstrate the diagnostic value of CT scanning for periventricular leukomalacia during late infancy and childhood. Although serial ultrasonography during the first weeks of life may be diagnostic of periventricular leukomalacia, it is of less value later. In contrast, CT scans obtained beyond 6 months of age can demonstrate a characteristic pattern of abnormalities that may be considered diagnostic of periventricular leukomalacia.