Fetal cerebellar hemorrhage in parvovirus-associated non-immune hydrops fetalis

Fetal Intraparenchymal Hemorrhage Imaging Patterns, Etiology, and Outcomes: A Single Center Cohort Study

OBJECTIVE

This study examines associations among fetal brain magnetic resonance imaging (MRI) injury patterns, etiologies, and outcomes in fetal intraparenchymal hemorrhage (IPH).

METHODS

This is a retrospective, single-center cohort study of IPH diagnosed on fetal MRI (1996-2022). IPH and associated abnormalities were categorized by 2 pediatric neuroradiologists; electronic medical records were reviewed by 2 pediatric neurologists to classify etiology and outcomes including cerebral palsy, epilepsy, developmental delay, and death.

RESULTS

Forty-four fetuses with IPH were identified (34 singleton and 10 twin gestations) with MRI at median 24 weeks gestation (interquartile range [IQR] = 22-28 weeks). IPH was commonly supratentorial (84%) and focal (50%) or focal with diffuse injury (43%) and was often associated with germinal matrix hemorrhage (GMH; 75%) and/or intraventricular hemorrhage (IVH; 52%). An etiology was identified in 75%, including twin-twin transfusion syndrome (TTTS, n = 10), COL4A1/2 variants (n = 8), or other fetal/maternal conditions (n = 15). COL4A1/2 variants were associated with focal IPH and the presence of hemorrhagic porencephaly, and intrauterine transfusion was associated with infratentorial hemorrhage. Twenty-two fetuses were liveborn, and 18 pregnancies were terminated. Among those with follow-up ≥ 12 months (median = 7 years), 12 of 13 had cerebral palsy, 6 of 13 had developmental delay, and 5 of 13 had epilepsy.

INTERPRETATION

An etiology for fetal IPH with or without GMH-IVH is identified in most cases in our cohort and is commonly TTTS, COL4A1/2 variants, or other maternal/fetal comorbidities. Pattern of fetal IPH on MRI is associated with etiology. Cerebral palsy and neurodevelopmental impairment were common in liveborn infants. Genetic studies should be considered in cases of fetal IPH without an otherwise apparent cause. ANN NEUROL 2024.

From Fetal to Neonatal Neuroimaging in TORCH Infections: A Pictorial Review

Congenital infections represent a challenging and varied clinical scenario in which the brain is frequently involved. Therefore, fetal and neonatal neuro-imaging plays a pivotal role in reaching an accurate diagnosis and in predicting the clinical outcome. Congenital brain infections are characterized by various clinical manifestations, ranging from nearly asymptomatic diseases to syndromic disorders, often associated with severe neurological symptoms. Brain damage results from the complex interaction among the infectious agent, its specific cellular tropism, and the stage of development of the central nervous system at the time of the maternal infection. Therefore, neuroradiological findings vary widely and are the result of complex events. An early detection is essential to establishing a proper diagnosis and prognosis, and to guarantee an optimal and prompt therapeutic perinatal management. Recently, emerging infective agents (i.e., Zika virus and SARS-CoV2) have been related to possible pre- and perinatal brain damage, thus expanding the spectrum of congenital brain infections. The purpose of this pictorial review is to provide an overview of the current knowledge on fetal and neonatal brain neuroimaging patterns in congenital brain infections used in clinical practice.

Ultrasound of acquired posterior fossa abnormalities in the newborn

Neonatal brain sonography is part of routine clinical practice in neonatal intensive care units, but ultrasound imaging of the posterior fossa has gained increasing attention since the burden of perinatal acquired posterior fossa abnormalities and their impact on motor and cognitive neurodevelopmental outcome have been recognized. Although magnetic resonance imaging (MRI) is often superior, posterior fossa abnormalities can be suspected or detected by optimized cranial ultrasound (CUS) scans, which allow an early and bed-side diagnosis and monitoring through sequential scans over a long period of time. Different ultrasound appearances and injury patterns of posterior fossa abnormalities are described according to gestational age at birth and characteristics of the pathogenetic insult. The aim of this review article is to describe options to improve posterior fossa sequential CUS image quality, including the use of supplemental acoustic windows, to show standard views and normal ultrasound anatomy of the posterior fossa, and to describe the ultrasound characteristics of acquired posterior fossa lesions in preterm and term infants with effect on long-term outcome. The limitations and pitfalls of CUS and the role of MRI are discussed.

Viral Infections and the Neonatal Brain

This review includes the congenital infections best known by the acronym TORCH (Toxoplasma gondii, rubella virus, cytomegalovirus, and herpes virus), as well as Zika virus infection and perinatally acquired infections (enterovirus, parechovirus, rotavirus, parvovirus). Congenital infections are due to pathogens that can cross the placenta and are more likely to injure the brain when the infection occurs early in pregnancy. There are many similarities, with regards to brain lesions, for congenital Zika syndrome and congenital cytomegalovirus infection. Perinatally acquired viral infections tend to injure the white matter, with cystic evolution being more likely in the (late) preterm infant compared to the full-term infant. Congenital and perinatally acquired viral infections can be associated with adverse neurological outcomes. Prevention is important, especially as therapeutic options are limited. In this review both congenital as well as perinatally acquired viral infections will be discussed with a focus on neuro-imaging findings.

Parvovirus B19 infection during pregnancy and risks to the fetus

Parvovirus B19 infects 1 to 5% of pregnant women, generally with normal pregnancy outcomes. During epidemics, the rate of infection is higher. Major congenital anomalies among offspring of infected mothers are rare, as the virus does not appear to be a significant teratogen. However, parvovirus B19 infection may cause significant fetal damage, and in rare cases, brain anomalies and neurodevelopmental insults, especially if infection occurs in the first 20 weeks of pregnancy. Parvovirus B19 is also an important cause of fetal loss, especially in the second half of pregnancy when spontaneous fetal loss from other causes is relatively rare. Parvovirus B19 infection may affect many fetal organs and can cause severe anemia, following fetal erythroid progenitor cells infection and apoptosis, especially in fetuses, that have shortened half-life of erythrocytes. Severe anemia may cause high output cardiac failure and nonimmune hydrops fetalis. In addition, parvovirus B19 may directly infect myocardial cells and produce myocarditis that further aggravates the cardiac failure. Intrauterine fetal transfusion is commonly used for the treatment of severe fetal anemia with survival rates of 75 to 90% and significant reduction of fetal morbidity. Only 66 cases were evaluated neurodevelopmentally, of which 10 (16%) had slight or severe neurodevelopmental problems. Because parvovirus B19 infection can cause severe fetal morbidity and mortality, it should be part of the routine work-up of pregnant women who have been exposed to the virus or of pregnancies with suspected fetal hydrops. Assessment for maternal infection during pregnancy is especially important during epidemics, when sero-conversion rates are high. Birth Defects Research 109:311-323, 2017. © 2017 Wiley Periodicals, Inc.

Cerebellar hemorrhage in utero associated with ‘massive’ fetal thrombotic vasculopathy

Background: Cerebellar hemorrhage is a rare but serious perinatal condition with various etiologies leading to fetal and neonatal death and adverse neurological complications. Complete autopsy and placental examination are essential for identification of a cause of the bleeding. Objective: Present a case of cerebellar hemorrhage in utero associated with ‘massive’ fetal thrombotic vasculopathy (FTV). Method: Autopsy of a stillborn female fetus, 26 weeks gestation, with intrauterine growth restriction, delivered by a 37-year-old woman. Results: The fetus showed multiple recent peticheal hemorrhages along the cerebellar cortex. The placenta revealed a large thrombosed chorionic blood vessel. Microscopic findings showed multiple vascular thrombosis and massive FTV throughout the placental villi. These were recognized as two histologic patterns, ‘early’ stromal karryorhxis, and ‘late’ villous stromal involution. Conclusion: Massive FTV was a leading cause of fetal stress due to increased resistant of downstream placental villi. This longstanding stressful environment induced auto-regulation impairment of fetal cerebral blood flow resulting in cerebellar parenchymal bleeding. Careful placental examination is beneficial for understating the mode and mechanism of fetal death.

Fetal anemia, cerebellar hemorrhage and hypoplasia associated with congenital Parvovirus infection

We report a case of fetal cerebellar hemorrhage and hypoplasia, identified by fetal MRI after intrauterine blood transfusion at 21 weeks' gestation for treatment of severe anemia due to congenital Parvovirus infection. Postnatal MRI confirmed atrophy of bilateral cerebellar hemispheres and inferior vermis. Cerebellar capillaries may be extremely susceptible to hemodynamic changes in the setting of intrauterine blood transfusion due to severe anemia. Although the correlation between fetal intracranial anomalies and Parvovirus infection remains unclear, in this population, a detailed evaluation of the brain parenchyma should be considered prior to and after intrauterine blood transfusion.

Prenatal brain MRI of fetuses with Zika virus infection

BACKGROUND

An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage.

OBJECTIVE

To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection.

MATERIALS AND METHODS

We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans.

RESULTS

Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1).

CONCLUSION

Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections.

Prenatal MR imaging features of isolated cerebellar haemorrhagic lesions

OBJECTIVE

Prenatal features of isolated cerebellar haemorrhagic lesions have not been sufficiently characterised. We aimed to better define their MR imaging characteristics, documenting the location, extension, evolution stage and anatomic sequelae, and to better understand cerebellar haemorrhage pathophysiology.

MATERIALS AND METHODS

We screened our foetal MR imaging database (3200 cases) for reports of haemorrhagic lesions affecting only the cerebellum (without any supratentorial bleeding or other clastic lesions), defined as one of the following: T2-weighted hypointense or mixed hypo-/hyperintense signal; rim of T2-weighted hypointense signal covering the surface of volume-reduced parenchyma; T1-weighted hyperintense signal; increased DWI signal.

RESULTS

Seventeen cases corresponded to the selection criteria. All lesions occurred before the 26th week of gestation, with prevalent origin from the peripheral-caudal portion of the hemispheres and equal frequency of unilateral/bilateral involvement. The caudal vermis appeared affected in 2/3 of cases, not in all cases confirmed postnatally. Lesions evolved towards malformed cerebellar foliation. The aetiology and pathophysiology were unknown, although in a subset of cases intra- and extracranial venous engorgement seemed to play a key role.

CONCLUSIONS

Onset from the peripheral and caudal portion of the hemispheres seems characteristic of prenatal cerebellar haemorrhagic lesions. Elective involvement of the peripheral germinal matrix is hypothesised.

KEY POINTS

• The cerebellum can be vulnerable to bleeding during foetal development. • Isolated cerebellar haemorrhages can be seen on prenatal MRI. • In our cohort, isolated foetal cerebellar haemorrhages occurred before the 26th gestational week. • Haemorrhagic lesions happening in utero could look like malformations on post-natal MRI. • Venous engorgement could have a role in causing cerebellar haemorrhagic lesions.

Prenatal cerebellar hemorrhage: fetal and postnatal neuroimaging findings and postnatal outcome

BACKGROUND

Despite significant progress in fetal neuroimaging techniques, only a few well-documented examples of prenatal cerebellar hemorrhages are available in the literature. In the majority of these individuals, the diagnosis of prenatal cerebellar hemorrhages led to termination of pregnancy or death occurred in utero; data about postnatal outcome of children with prenatal diagnosis of cerebellar hemorrhages are scant. We describe fetal and postnatal neuroimaging findings and the neurodevelopmental outcome of a child with a large cerebellar hemorrhage that occurred at approximately 27 weeks' gestation.

METHOD

Data about neurological features and neurodevelopmental outcome were collected from the clinical history and follow-up examination. All pre- and postnatal MRI data were qualitatively evaluated for infra- and supratentorial abnormalities.

RESULTS

Fetal MRI at 27 weeks' gestation showed a T1-hyperintense and T2-hypointense lesion within the cerebellum suggestive of bilateral cerebellar hemorrhages with extension into the adjacent subarachnoid, subdural, and intraventricular spaces. The prenatal cerebellar hemorrhage was possibly related to maternal sepsis. Postnatal MRI showed encephalomalacic changes involving the vermis and both cerebellar hemispheres. Neurodevelopmental follow-up at 15 months of age was concerning for global developmental delay and significant right esotropia.

CONCLUSION

This child illustrates (1) the role of prenatal neuroimaging in the diagnosis of fetal cerebellar hemorrhages, (2) the significance of cerebellar involvement for neurodevelopment, and (3) the importance of the collection of postnatal outcome data in children with prenatal diagnosis of cerebellar hemorrhage.

Cerebellar hemorrhage in very low birth weight premature infants: the advantage of the posterolateral fontanelle view

OBJECTIVE

The purpose of this study was to determine the prevalence of cerebellar hemorrhage in very low birth weight infants using the posterolateral fontanelle for ultrasound (US) examination.

METHODS

The study included 125 very low birth weight premature infants (defined as equal or less than 1500 grams at birth) hospitalized in the premature or neonatal intensive care departments that had at least one head US examination including both anterior and posterolateral fontanelle scans.

RESULTS

On US performed through the posterolateral fontanelle, four (3.2%) infants had echogenic posterior fossa lesions interpreted as hemorrhages. None of these lesions were initially or retrospectively observed through the standard anterior fontanelle scan. Two infants died at age 4 and 39 days, respectively. All survivors are being followed up in the hospital's neurodevelopment outpatient clinic.

CONCLUSIONS

Cerebellar hemorrhage may be overlooked on standard anterior fontanelle views. The posterolateral approach may assist in diagnosing these lesions.

Diagnosis of in utero Parvovirus B19 infection and maternal immune response - the relevance of linear epitopes and advanced serologic testing

IMPORTANCE OF THE FIELD

Parvovirus B19 (B19V) infection in utero causing fetal anemia and non-immune hydrops fetalis (NIHF) is a potentially life-threatening event for the fetus. Postexpositional non-invasive diagnosis is based on maternal IgG/IgM response and detection of viral genome in maternal blood. Serologic testing directs prenatal follow-up. Fetal infection is confirmed by polymerase chain reaction or in situ hybridization in fetal blood and/or amniotic fluid cells. The performance of serologic tests is significant in order to direct pre- and perinatal care at rational use of resources. Timing of diagnostic procedures and knowledge of the time course of infection in pregnant, asymptomatic women are critical. IgM negative testing in the presence of prolonged viremia may complicate individual risk analysis in pregnancy. Recently, advanced IgG avidity assays and epitope-type specific assays (IgG ETS EIA) have been re-evaluated.

AREAS COVERED IN THIS REVIEW

Epidemiology, clinical relevance and management of B19V infection in pregnancy. A review of the current literature (November 1984 - May 2009) and evaluation of current information on performance and predictive value of molecular and VP1/VP2 antigen-based IgG tests directed at the diagnosis of materno-fetal B19V infection and detection of past immunity. New aspects of B19V-associated fetal disease other than anemia/NIHF are also covered.

WHAT THE READER WILL GAIN

An overview of immunology and clinical relevance of B19V infection in pregnancy, of the potential value of advanced serologic testing and fields of future research.

TAKE HOME MESSAGE

In the absence of a commercially available vaccine, serologic tests remain important tools in individual risk analysis of pregnant women exposed to B19V. Sequential application of IgG avidity and IgG ETS EIAs may improve risk stratification and timing of invasive testing in B19V-exposed pregnancies, in particular with IgM-negativity and/or persistent DNAemia. Prospective evaluation of these test systems correlated to fetal outcome in order to reduce fetal morbidity and mortality as well as the overall burden of disease of B19V with regard to fetal malformation may be subject to future research.

Polymicrogyria in a fetus with human parvovirus B19 infection: a case with radiologic-pathologic correlation

We report the prenatal magnetic resonance imaging (MRI) appearance of polymicrogyria with pathologic correlation in a fetus with congenital parvovirus B19 infection. Prenatal ultrasound revealed non-immune hydrops, but detected no fetal brain abnormalities. A subsequent fetal MRI scan performed at 23 weeks' gestation demonstrated bilateral polymicrogyria, which was confirmed at autopsy. To our knowledge, prenatal diagnosis of polymicrogyria in association with congenital parvovirus B19 infection has not been previously described. This case provides further evidence for brain abnormalities resulting from congenital parvovirus B19 infection, and suggests that fetal neuroimaging with MRI would be of value in suspected cases of congenital parvovirus infection.

Brain ultrasound findings in neonates treated with intrauterine transfusion for fetal anaemia

BACKGROUND

The main causes of severe fetal anaemia are red-cell allo-immunization, parvo B19 virus infection and feto-maternal haemorrhage. Treatment consists of intrauterine transfusion (IUT). Neuro-imaging studies in surviving neonates treated with IUT are scarce.

AIMS

To assess if neonates treated with IUT for fetal anaemia are at risk for cerebral injury, report the incidence and severity of brain ultrasound (US) abnormalities and explore the relation between brain US findings and perinatal parameters and neurological outcome.

PATIENTS AND METHODS

Brain US scans of neonates born alive between 2001 and 2008 with at least one IUT were retrospectively reviewed and classified as normal, mildly or moderately/severely abnormal. Incidences of abnormalities were calculated for full-term and preterm neonates. Presence and severity of abnormalities were related to clinical and IUT related parameters and to neurological outcome around 2 years of age (adverse: moderate or severe disability; favourable: normal or mild disability).

RESULTS

A total of 127 neonates (82 born preterm) were included. Median number of IUTs was 3 (range 1-6) and of brain US 2 (1-6). Median gestational age and weight at birth were 36.6 (26.0-41.1) weeks and 2870 (1040-3950)g. In 72/127 (57%) neonates ≥1 abnormality was seen on brain US, classified as moderate/severe in 30/127 (24%). Neurological outcome was adverse in 5 infants. Presence of brain US abnormalities was not significantly related to any of the perinatal parameters or to neurological outcome.

CONCLUSIONS

Neonates undergoing IUT for fetal anaemia are at high risk of brain injury.

Unusual high rate of asymptomatic maternal parvovirus B19 infection associated with severe fetal outcome

OBJECTIVE

To study the role of asymptomatic maternal parvo B19 infection in severe fetal outcome in Province of Vojvodina.

METHODS

One hundred seventy-six pregnant women (13-25 weeks of gestation) were divided in two groups - patients with symptoms of imminent spontaneous abortion and poor pregnancy outcome and patients with normal course of pregnancy. Double serum samples were analyzed to quantify IgM and IgG to parvovirus B19.

RESULTS

Among pregnant women with symptoms of spontaneous abortion, we found significantly higher percentage of acute parvovirus B19 infection.

CONCLUSIONS

Asymptomatic parvo B19 infection is associated with poor fetal outcome much more than we presumed previously.

MR imaging of the fetal brain

Fetal MRI is clinically performed to evaluate the brain in cases where an abnormality is detected by prenatal sonography. These most commonly include ventriculomegaly, abnormalities of the corpus callosum, and abnormalities of the posterior fossa. Fetal MRI is also increasingly performed to evaluate fetuses who have normal brain findings on prenatal sonogram but who are at increased risk for neurodevelopmental abnormalities, such as complicated monochorionic twin pregnancies. This paper will briefly discuss the common clinical conditions imaged by fetal MRI as well as recent advances in fetal MRI research.