Fetal intracranial hemorrhage (fetal stroke): does grade matter?

Fetal intracerebral hemorrhage and cataract: think COL4A1

The COL4A1 gene encodes the alpha1 chain of type IV collagen, a crucial component of nearly all basement membranes. Mutations in COL4A1 were first associated with cerebral microangiopathy and familial porencephaly. Recently, several authors have reported mutations in COL4A1 as a Mendelian cause of prenatal onset intracranial hemorrhage (ICH). We report two cases of prenatal ICH associated with cataract and suggest that COL4A1 mutation should be envisaged in fetuses with prenatal ICH, especially in the presence of lens abnormalities at ultrasound examination.

Lethal fetal stroke in utero

OBJECTIVE

Fetal intracranial hemorrhage (ICH) in utero is a rare complication of pregnancy associated with subsequent neurological sequelae or fetal death.

CASE REPORT

A 34-year-old woman with Crohn's disease presented at 36 weeks' gestation due to decreased fetal movement. Fetal heart-rate tracing indicated poor beat-to-beat variability. In addition, a Doppler ultrasonography suggested a prenatal stroke with evidences of ICH, reverse-end diastolic velocity of the middle cerebral artery, and a persistent distended bladder. A nonaggressive treatment option was chosen after counseling about the unfavorable prognosis. However, 22 hours after her admission, intrauterine fetal death occurred.

CONCLUSION

Fetal ICH in utero might be a rare yet lethal complication of Crohn's disease in pregnancy.

Can noninvasive brain stimulation measure and modulate developmental plasticity to improve function in stroke-induced cerebral palsy?

The permanent nature of motor deficits is a consistent cornerstone of cerebral palsy definitions. Such pessimism is disheartening to children, families, and researchers alike and may no longer be appropriate for it ignores the fantastic plastic potential of the developing brain. Perinatal stroke is presented as the ideal human model of developmental neuroplasticity following distinct, well-defined, focal perinatal brain injury. Elegant animal models are merging with human applied technology methods, including noninvasive brain stimulation for increasingly sophisticated models of plastic motor development following perinatal stroke. In this article, how potential central therapeutic targets are identified and potentially modulated to enhance motor function within these models is discussed. Also, future directions and emerging clinical trials are reviewed.

Modeling developmental plasticity after perinatal stroke: defining central therapeutic targets in cerebral palsy

Perinatal stroke is presented as the ideal human model of developmental neuroplasticity. The precise timing, mechanisms, and locations of specific perinatal stroke diseases provide common examples of well defined, focal, perinatal brain injuries. Motor disability (hemiparetic cerebral palsy) constitutes the primary adverse outcome and the focus of models explaining how motor systems develop in health and after early injury. Combining basic science animal work with human applied technology (functional magnetic resonance imaging, diffusion tensor imaging, and transcranial magnetic stimulation), a model of plastic motor development after perinatal stroke is presented. Potential central therapeutic targets are revealed. The means to measure and modulate these targets, including evidence-based rehabilitation therapies and noninvasive brain stimulation, are suggested. Implications for clinical trials and future directions are discussed.

Imaging diagnosis of congenital brain anomalies and injuries

Fetal brain is rapidly developing and changing its appearance week by week during pregnancy. The brain is the most important organ but it is quite hard to observe detailed structure of this organ by conventional transabdominal sonography. Transvaginal high-resolution ultrasound and three-dimensional (3D) ultrasound has been a great diagnostic tool for evaluation of three-dimensional structure of fetal central nervous system (CNS). This method has contributed to the prenatal assessment of congenital CNS anomalies, intracranial vascular anomalies and acquired brain damage in utero. It is possible to observe the whole brain structure by magnetic resonance imaging in the post half of pregnancy but transvaginal high-resolution 3D ultrasound is certainly powerful modality as well for understanding brain anatomy. Longitudinally and carefully evaluation of neurological short- or long-term prognosis should be required according to precise prenatal diagnosis, for proper counseling and management based on precise evidence.

Magnetic resonance methods in fetal neurology

Fetal magnetic resonance imaging (MRI) has become an established clinical adjunct for the in-vivo evaluation of human brain development. Normal fetal brain maturation can be studied with MRI from the 18th week of gestation to term and relies primarily on T2-weighted sequences. Recently diffusion-weighted sequences have gained importance in the structural assessment of the fetal brain. Diffusion-weighted imaging provides quantitative information about water motion and tissue microstructure and has applications for both developmental and destructive brain processes. Advanced magnetic resonance techniques, such as spectroscopy, might be used to demonstrate metabolites that are involved in brain maturation, though their development is still in the early stages. Using fetal MRI in addition to prenatal ultrasound, morphological, metabolic, and functional assessment of the fetus can be achieved. The latter is not only based on observation of fetal movements as an indirect sign of activity of the fetal brain but also on direct visualization of fetal brain activity, adding a new component to fetal neurology. This article provides an overview of the MRI methods used for fetal neurologic evaluation, focusing on normal and abnormal early brain development.

Classification of clinical semiology in epileptic seizures in neonates

The clinical semiology of 61 neonatal seizures with EEG correlates, in 24 babies was analysed. Most seizures (89%) had multiple features during the EEG discharge. The seizures were classified using the prominent clinical feature at onset, and all features seen during the seizure, using an extended classification scheme. Orolingual features occurred most frequently at onset (30%), whereas ocular phenomena occurred most often during the seizure (70%). Orolingual, ocular and autonomic features were seen at onset in 55% of the seizures. Seizure onsets with clonic, tonic and hypomotor features were seen in 20%, 8% and 18% respectively. Clinico-electrical correlations were as follows. The EEG discharge involved both hemispheres in 54% of all seizures, in clonic seizures this was 93%. Focal clonic seizures were associated with EEG seizure onset from the contralateral hemisphere. Majority of the clonic and hypomotor seizures had a left hemisphere ictal EEG onset. Orolingual seizures frequently started from the right hemisphere, whereas ocular and autonomic seizures arose from either hemisphere. There was no significant difference in mortality, morbidity, abnormal neuroimaging and EEG background abnormalities in babies with or without clonic seizures. This study provides insights into neuronal networks that underpin electroclinical seizures, by analysing and classifying the obvious initial clinical features and those during the seizure.

The black box of perinatal ischemic stroke pathogenesis

An improved understanding of perinatal stroke epidemiology, classification, neuroimaging, and outcomes has emerged in recent years. Despite this, little is known regarding the pathophysiological mechanisms responsible for most cases. A multitude of possible associations and putative risk factors have been reported, but most lack definitive empirical evidence supporting primary causation. These include obstetrical and maternal factors, perinatal conditions, infectious diseases, prothrombotic abnormalities, cardiac disorders, medications, and many others. The bulk of evidence is weak, dominated by case reports and retrospective case series. Findings from the small number of case-control and cohort studies that exist are limited by heterogeneous populations and methodologies. The single largest barrier to ultimately understanding and potentially improving outcomes from this common and disabling condition is the lack of comprehensive, fully powered risk factor studies required to definitively describe perinatal stroke pathogenesis. This review summarizes current evidence and suggests future directions for research.

Grade IV fetal intracranial hemorrhage with good cognitive function

Fewer than 200 cases of prenatally diagnosed magnetic resonance imaging-confirmed fetal intracranial hemorrhage have been reported. Children surviving grade IV fetal intracranial hemorrhage usually manifest severe impairments, including mental retardation. We report on a child with a grade IV intracranial hemorrhage diagnosed by in utero ultrasound at 28 weeks of gestation, and confirmed by fetal magnetic resonance imaging at 29 weeks of gestation. At age 27 months, she has a ventriculoperitoneal shunt and exhibits hemiplegic cerebral palsy, but without seizures, and with normal cognitive function and excellent verbal ability. We discuss how perinatal care may have contributed to her good outcome.

Fetal general movements and brain sonography in a population at risk for preterm birth

BACKGROUND

General movements (GMs) assessed three months post term are related to brain injury and neurological outcome.

AIMS

To study GMs in fetuses and their predictive value for echogenicity changes in the fetal brain.

STUDY DESIGN

Prospective study of fetal GMs (classified as normal or abnormal) and echogenicity changes in the periventricular, basal ganglia/thalami area, and ventricular system (classified as absent, mild or moderate).

SUBJECTS

121 fetuses from pregnancies affected by hypertensive disorders and/or preterm labour, at risk for preterm birth (26-34weeks gestational age).

OUTCOME MEASURES

Prevalence of abnormal GMs, GM parameters (amplitude, speed and complexity), and moderate echogenicity changes in the fetal brain (periventricular >or=IB, intraventricular grade II/III, and basal ganglia/thalamus locally increased). Predictive values of GMs for clinical parameters and moderate echogenicity changes.

RESULTS

GMs were abnormal in 58%, with amplitude affected in 96%, and speed and complexity in 59%. Abnormal GMs correlated with oligohydramnios (p=0.002) and hypertensive disorders (p=0.015). Echogenicity changes of the brain were absent, mild and moderate in 27%, 39% and 31%, respectively. The sensitivity of GMs for moderate echogenicity changes in the three areas combined was 0.65, and the periventricular area 0.85, specificity both 0.44, negative predictive values 0.73 and 0.96 respectively.

CONCLUSIONS

Qualitative abnormal GMs are frequent in fetuses of compromised pregnancies, and correlate with hypertensive disorders and oligohydramnios. The amplitude of GMs was most frequently affected. Abnormal GMs relate to moderate echogenicity changes especially in the periventricular area of the fetal brain, while normal GMs predict absence of moderate echogenicity changes.

What is the clinical importance of echogenic material in the fetal frontal horns?

OBJECTIVE

The purpose of this study was to evaluate the importance of echogenic material in the fetal frontal horns.

METHODS

This was a Health Insurance Portability and Accountability Act-compliant, Institutional Review Board-approved retrospective study. In part 1 of the study, prenatal sonography, prenatal magnetic resonance imaging (MRI), and birth outcomes of 17 fetuses (mean gestational age, 19 weeks; range, 15-34 weeks) with prospective echogenic material in the frontal horns were assessed. In part 2, 400 consecutive sonographic fetal surveys (mean gestational age, 19 weeks; range, 15-38 weeks) were reviewed to determine the incidence. In part 3, 2 independent reviewers assessed the appearance of the frontal horns in 40 fetuses (20 with suspected intraventricular hemorrhage from parts 1 and 2 and 20 who were interpreted to have normal findings in part 2).

RESULTS

Part 1 of the study showed that suspected hemorrhage was unilateral in 13 fetuses and bilateral in 4. Additional findings by sonography were grade 4 intraventricular hemorrhage (n = 2), ventriculomegaly (n = 2), and porencephaly (n = 1). An additional finding by MRI was porencephaly in 1 fetus. In part 2, echogenic material in the frontal horns was identified in 3 of 400 fetuses (0.8%). In part 3, hemorrhage was probably or definitely present in 11 of the 20 fetuses with abnormalities; material looked like a cyst in 6; and normal choroid was in an abnormal position in 2 and a normal position 1. Of 19 fetuses with abnormalities, 14 had a posteriorly symmetric choroid; 9 had material of different echogenicity compared with the choroid; and 17 had an expanded frontal horn. Birth outcomes were abnormal in 7, including platelet abnormalities (n = 2), hemorrhage on imaging or pathologic examination (n = 2), extraventricular hemorrhage (n = 3), and ventriculomegaly (n = 3).

CONCLUSIONS

The incidence of echogenic material in the frontal horns is less than 1%. This does not represent the normal location of the choroid plexus and may represent hemorrhage, which may resolve without sequelae or result in ventriculomegaly and porencephaly.

Counseling in isolated mild fetal ventriculomegaly

In this Review we aim to provide up-to-date and evidence-based answers to the common questions regarding the diagnosis of isolated mild fetal ventriculomegaly (VM). A literature search was performed to identify all reports of antenatal VM in the English language literature. In addition, reference lists of articles identified using the search were scrutinized to further identify relevant articles. Fetal mild VM is commonly defined as a ventricular atrial width of 10.0-15.0 mm, and it is considered isolated if there are no associated ultrasound abnormalities. There is no good evidence to suggest that the width of the ventricular atria contributes to the risk of neurodevelopmental outcome in fetuses with mild VM. The most important prognostic factors are the association with other abnormalities that escape early detection and the progression of ventricular dilatation, which are reported to occur in about 13% and 16% of cases, respectively. Most infants with a prenatal diagnosis of isolated mild VM have normal neurological development at least in infancy. The rate of abnormal or delayed neurodevelopment in infancy is about 11%, and it is unclear whether this is higher than in the general population. Furthermore, the number of infants that develop a real handicap is unknown. There are limitations of existing studies of mild VM. Although they address many of the relevant questions regarding the prognosis and management of fetal isolated mild VM, there is a lack of good-quality postnatal follow-up studies. The resulting uncertainties make antenatal counseling for this abnormality difficult.

Frühkindliche Schlaganfälle - Studie zur klinischen Validität des ET 6-6

Zusammenfassung: Hintergrund: Untersucht werden soll die Einsatzmöglichkeit des ET 6-6 (Entwicklungstest 6 Monate bis 6 Jahre) zur Einschätzung von Entwicklungsdefiziten bei frühkindlichem Schlaganfall. Material und Methoden: 32 Kinder mit frühkindlichem Schlaganfall wurden im Alter zwischen 36 bis 72 Monaten mit dem ET 6-6 untersucht. Die Ergebnisse werden mit den Leistungen einer altersparallelisierten Kontrollgruppe aus der Normierungsstichprobe verglichen. Anschließend erfolgt ein deskriptiver Leistungsvergleich nach Lokalisation der zerebralen Schädigung. Ergebnisse: Im Gesamtgruppenvergleich zeigt die Untersuchungsgruppe in fast allen Entwicklungsdimensionen signifikant niedrigere Leistungen als die Kontrollgruppe. Die gefundenen Leistungsdiskrepanzen werden durch den Einbezug der Lokalisation des Schlaganfalles spezifiziert; nach Schlaganfällen im Bereich der A. cerebri media linksseitig zeigen sich die deutlichsten Entwicklungsrisiken. Diskussion: Der Einsatz des ET 6-6 zeigt sich als Überblicksverfahren geeignet, um gravierende Entwicklungsdefizite oder Entwicklungsrisiken in verschiedenen Dimensionen bei frühkindlichem Schlaganfall aufzuzeigen.

Changes in echogenicity in the fetal brain: a prevalence study in fetuses at risk for preterm delivery

OBJECTIVES

To study the incidence of echodensities in the periventricular white matter, ventricular system, basal ganglia and thalamus of the brain in fetuses at risk for preterm delivery.

METHODS

This was a prospective study of 124 fetuses with a gestational age between 26 and 34 weeks in pregnancies affected by either pregnancy-induced hypertensive disorders or preterm labor. Transvaginal ultrasound examination of the fetal brain in coronal and sagittal planes was performed weekly until delivery and the neonatal brain was examined within 24 h after delivery.

RESULTS

In 66% of all fetuses, echodensities were found in one or more areas of the brain. They were present in the periventricular area in 52% of cases, the intraventricular area in 18% and in the basal ganglia and thalamus area in 28%. Changes in echogenicity were seen throughout the entire gestational-age period studied. Of the periventricular echodensities that exceeded in echodensity that of the choroid plexus, at least 50% persisted after delivery; at least 38% of the intraventricular echodensities and at least 32% of the basal ganglia and thalamus echodensities persisted after delivery.

CONCLUSIONS

In high-risk fetuses, echodensities are a frequent finding in several areas in the brain. How far these echodensities are related to future outcome of the infant needs to be investigated.

Fetal intracranial hemorrhage (fetal stroke): report of four antenatally diagnosed cases and review of the literature

OBJECTIVE

Neonatal intracranial hemorrhage (ICH) has been estimated to be high in premature infants, occurring in approximately 40% of infants of less than 32 weeks' gestation. However, the true incidence of ICH in utero has not been determined. We present our experience with four cases of fetal ICH (fetal stroke), which was detected prenatally by ultrasonography (US).

MATERIALS AND METHODS

Four cases of fetal ICH were identified over a 2-year period at the prenatal unit of Taichung Veterans General Hospital, Taiwan. Prenatal and neonatal sonograms, computed tomography (CT) scan or magnetic resonance imaging (MRI), medical records, and the clinical course were assessed retrospectively. In each case, a series of initial and follow-up obstetric sonograms were available. Fetal stroke was recognized by several sonographic features: irregular echogenic brain mass, intraventricular echogenic foci or periventricular echodensities; ventriculomegaly; and posthemorrhagic hydrocephalus (PHH). A detailed investigation for possible etiology of fetal ICH was performed in all cases.

RESULTS

Transabdominal US showed hyperechoic lesions in the lateral ventricle and ventriculomegaly in three of the four fetuses, and a massive intraparenchymal hemorrhage in the remaining one. Three fetuses were born vaginally and one by cesarean section due to an enlarged head circumference. Abnormal nonstress tests and abnormal flow velocity waveforms in the umbilical and middle cerebral arteries were present in two cases. Intrapartum fetal death and neonatal death occurred in the first two cases associated with maternal preeclampsia at 31 and 27 weeks, respectively. In the remaining two infants, the one in case 3 underwent ventriculoperitoneal shunting, which developed normally at the age of 18 months. The other infant in case 4 had PHH after suspicious choroids plexus hemorrhage, and the detailed information regarding the cause of neonatal death was not available.

CONCLUSION

This small series demonstrate that an antenatal diagnosis of fetal stroke with intraventricular hemorrhage Grades III and IV or with brain parenchymal involvement appears to be associated with poor neurologic outcome. Due to the significant neonatal neurologic impairment and potential medicolegal implications of antepartum fetal ICH, it follows that obstetricians and sonographers should be familiar with predisposing factors and typical diagnostic imaging findings of rare in utero ICH events.

Fetal brain monitoring: future applications

Future application of fetal brain monitoring is explored by selecting and analysing articles for information on types of brain damage that can be monitored, where in the brain this can be done, how long after the risk exposure, and with what method of investigation. A limited number of--mainly--case histories reported that early (cell death and oedema) and late (gliosis) effects of brain damage can be demonstrated before birth with multiplanar ultrasound and magnetic resonance imaging, and that hypoxic ischaemic injury or infection can induce local or widespread brain injury, occurring as transient or longer-lasting changes in age-related predilection areas for which normal features are known. The antenatal role of risk factors inducing abnormal brain development can be studied longitudinally with ultrasound and magnetic resonance imaging. A multidisciplinary approach will facilitate the introduction of various techniques with adequate know-how of underlying processes, to evaluate the predictive value on neurological outcome and prevent premature introduction into clinical application.

Normal and abnormal fetal brain development during the third trimester as demonstrated by neurosonography

The multiplanar neurosonographic examination of the fetus enables superb visualization of brain anatomy during pregnancy. The examination may be performed using a transvaginal or a transfundal approach and it is indicated in patients at high risk for CNS anomalies or in those with a suspicious finding during a routine examination. The purpose of this paper is to present a description of the normal brain and of abnormal findings usually diagnosed late in pregnancy, including malformations of cortical development, infratentorial anomalies, and prenatal insults.

MRI of fetal acquired brain lesions

Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images.