The spectrum of associated brain lesions in cerebral sinovenous thrombosis: relation to gestational age and outcome

Deep Medullary Vein Thrombosis in Newborns: A Systematic Literature Review

BACKGROUND

Deep medullary vein (DMV) thrombosis is a rare cause of brain damage in both preterm and full-term neonates. In this study, we aimed to collect data on clinical and radiological presentation, treatment, and outcome of neonatal DMV thrombosis.

METHODS

Systematic literature review on neonatal DMV thrombosis was carried out in PubMed, ClinicalTrial.gov, Scopus, and Web of Science up to December 2022.

RESULTS

Seventy-five published cases of DMV thrombosis were identified and analysed (preterm newborns were 46%). Neonatal distress, respiratory resuscitation, or need for inotropes were present in 34/75 (45%) of patients. Signs and symptoms at presentation included seizures (38/75, 48%), apnoea (27/75, 36%), lethargy or irritability (26/75, 35%). At magnetic resonance imaging (MRI), fan-shaped linear T2 hypointense lesions were documented in all cases. All had ischaemic injuries, most often involving the frontal (62/74, 84%) and parietal lobes (56/74, 76%). Signs of haemorrhagic infarction were present in 53/54 (98%). Antithrombotic treatment was not mentioned in any of the studies included. Although mortality was low (2/75, 2.6%), a large proportion of patients developed neurological sequelae (intellectual disability in 19/51 [37%] and epilepsy in 9/51 [18%] cases).

CONCLUSIONS

DMV thrombosis is rarely identified in the literature, even if it is possibly under-recognized or under-reported. Presentation in neonatal age is with seizures and non-specific systemic signs/symptoms that often cause diagnostic delay, despite the pathognomonic MRI picture. The high rate of morbidity, which determines significant social and health costs, requires further in-depth studies aimed at earlier diagnosis and evidence-based prevention and therapeutic strategies.

Cerebral Sinovenous Thrombosis in Infants and Children: A Practical Approach to Management

Cerebral sinovenous thrombosis (CSVT) is a rare, yet potentially devastating disorder, associated with acute complications and long-term neurologic sequelae. Consensus-based international pediatric CSVT treatment guidelines emphasize early clinical-radiologic recognition and prompt consideration for anticoagulation therapy. However, lack of clinical trials has precluded evidence-based patient selection, anticoagulant choice, optimal monitoring parameters and treatment duration. Consequently, uncertainties and controversies persist regarding anticoagulation practices in pediatric CSVT. This review focuses on commonly encountered issues that continue to pose questions and raise debates regarding anticoagulation therapy among pediatric neurologists and hematologists.

Cerebral Venous Sinus Thrombosis in Preterm Infants

BACKGROUND:

Neonatal cerebral venous sinus thrombosis (CVST) can lead to brain injury and neurodevelopmental impairments. Previous studies of neonatal CVST have focused on term infants, and studies of preterm infants are lacking. In this study, we examined the clinical and radiological features, treatment and outcome of CVST in preterm infants.

METHODS:

This was a retrospective, consecutive cohort study of preterm infants (gestational age <37 weeks) with radiologically confirmed CVST. All magnetic resonance imaging/MRV and CT/CTV scans were re-reviewed to study thrombus characteristics and pattern of brain injury. Outcome was assessed by the validated pediatric stroke outcome measure at the most recent clinic visit.

RESULTS:

Twenty-six preterm infants with CVST were studied. Of these, 65% were moderate-late preterm (32–37 weeks), 27% very preterm (28–32 weeks), and 8% extreme preterm (<28 weeks). Most (73%) were symptomatic at presentation with seizures or abnormal exam. Transverse (85%) and superior sagittal (42%) sinuses were common sites of thrombosis. Parenchymal brain injury was predominantly periventricular (35%) and deep white matter (31%) in location. Intraventricular hemorrhage occurred in 46%. Most infants (69%) were treated with anticoagulation. No treated infant (including eleven with pretreatment hemorrhage) had new or worsening post-treatment hemorrhage. Outcomes ranged from no deficits (50%), mild-moderate (25%), and severe (25%) impairment.

CONCLUSIONS:

In our sample of preterm infants with CVST, more than one-quarter were asymptomatic. White matter brain lesions predominated and one-half had neurological deficits at follow-up. Anticoagulation of preterm CVST in this small cohort appeared to be safe. Larger studies of preterm CVST are needed.

Multiple thrombosis of the cerebral venous sinuses, neonatal seizures, and minor parenchymal lesions: a case report and a review of the literature

BACKGROUND

Cerebral sinovenous thrombosis (CSVT) is a rare disease with potential catastrophic consequences. However, neonatal brain damage after venous injury and long-term neurologic outcomes have been poorly investigated. Some found an association between site and number of sinus occlusions, severity of lesions, clinical presentation and the neurodevelopmental outcome.

CASE PRESENTATION

We describe the case of a term newborn girl with multiple CSVT who presented with clonic seizures and who received early treatment with heparin. MRI scans showed a progressive recanalization of deep venous system, and only minor cerebral lesions were present at 3 months of life. Neurocognitive outcome was normal at 12 months of life.

CONCLUSIONS

This case demonstrates that multiple CSVT presenting with severe seizures does not necessarily underlie major cerebral lesions or lead to severely abnormal neurodevelopmental outcome.

Neonatal stroke in premature neonates

There are many neuro-imaging studies on the presence of brain lesions in the preterm infant, using cranial ultrasound (cUS) and/or term equivalent age MRI (TEA-MRI). These studies however tend to focus on germinal matrix-intraventricular hemorrhage (GMH-IVH) and white matter injury. Data about perinatal arterial ischemic stroke (PAIS) or cerebral sinovenous thrombosis (CSVT) in the preterm infant are very limited. In fact, several large cohort studies on neuro-imaging in preterm infants do not even mention neonatal stroke.^1-4 Most studies about PAIS exclude preterm infants.⁵ The aim of this review was to provide an update on neonatal stroke in the preterm infant, with a focus on neuro-imaging findings.

Clinical Profile and Long-Term Outcome in Neonatal Cerebral Sinus Venous Thrombosis

BACKGROUND

Neonatal cerebral sinus venous thrombosis (CSVT) causes high morbidity and mortality. Factors associated with either favorable or unfavorable long-term outcomes have not been clearly established. This study aimed to determine the factors involved in long-term neurological outcomes in patients with neonatal CSVT.

METHODS

This was a retrospective cohort study of patients with neonatal CSVT at a single institution. Clinical factors associated with long-term neurological outcomes were examined.

RESULTS

A total of 67 patients met study inclusion criteria for radiologically confirmed neonatal CSVT. The mean patient follow-up duration was four years (range one week to 16 years, median six years). We observed a favorable neurological outcome defined by a pediatric stroke outcome measures (PSOM) score of 0 to 0.5 in 26 (53%) of osurviving patients at follow-up. An unfavorable neurological outcome as defined by PSOM score >0.5 was observed in 23 survivors (47%). Death was reported in 18 (27%) patients, of which 10 patients died due to direct complications of CSVT. Congential heart disease and genetic disease were associated with significantly increased odds for all-cause death. Cardiorespiratory failure and altered mental status during the initial neurological examination were significantly associated with increased odds of death due to CSVT. Among surviving patients, higher PSOM scores were associated with premature birth (i.e., gestational age < 37 weeks), traumatic birth, site of thrombosis in the straight sinus, site of thrombosis in the internal cerebral veins, and hemorrhagic infarct. In contrast, lower PSOM scores were associated with a normal neurological examination at presentation, thrombosis in only superficial sinuses, and hemorrhage without infarct. There was no statistically significant association between the type and duration of CSVT treatment.

CONCLUSIONS

The major factors influencing outcome of neonates following CSVT included comorbid medical conditions, abnormal neurological examination at presentation, location of venous thrombosis, and type of cerebral injury. These results can help guide further studies in neonatal CSVT aiming to decrease morbidity and mortality with the goal of improving long-term neurological outcomes.

Epidemiology and pathogenesis of stroke in preterm infants: A systematic review

BACKGROUND:

Perinatal stroke is one of the principal causes of cerebral palsy (CP) in preterm infants. Stroke in preterm infants is different from stroke in term infants, given the differences in brain maturation and the mechanisms of injury exclusive to the immature brain. We conducted a systematic review to explore the epidemiology and pathogenesis of periventricular hemorrhagic infarction (PVHI), perinatal arterial ischemic stroke (PAIS) and cerebral sinovenous thrombosis (CSVT) in preterm infants.

METHODS:

Studies were identified based on predefined study criteria from MEDLINE, EMBASE, SCOPUS and WEB OF SCIENCE electronic databases from 2000 –2019. Results were combined using descriptive statistics.

RESULTS:

Fourteen studies encompassed 546 stroke cases in preterm infants between 23 –36 weeks gestational ages and birth weights between 450 –3500 grams. Eighty percent (436/546) of the stroke cases were PVHI, 17%(93/546) were PAIS and 3%(17/546) were CSVT. Parietal PVHI was more common than temporal and frontal lobe PVHI. For PAIS, left middle cerebral artery (MCA) was more common than right MCA or cerebellar stroke. For CSVT partial or complete thrombosis in the transverse sinus was universal. All cases included multiple possible risk factors, but the data were discordant precluding aggregation within a meta-analysis.

CONCLUSION:

This systematic review confirms paucity of data regarding the etiology and the precise causal pathway of stroke in preterm infants. Moreover, the preterm infants unlike the term infants do not typically present with seizures. Hence high index of clinical suspicion and routine cUS will assist in the timely diagnosis and understanding of stroke in this population.

Nosological Differences in the Nature of Punctate White Matter Lesions in Preterm Infants

Background: The pathogenesis of punctuate white matter lesions (PWMLs), a mild form of white matter damage observed in preterm infants, is still a matter of debate. Susceptibility-weighted imaging (SWI) allows to differentiate PWMLs based on the presence (SWI+) or absence (SWI-) of hemosiderin, but little is known about the significance of this distinction. This retrospective study aimed to compare neuroradiological and clinical characteristics of SWI+ and SWI- PWMLs. Materials and Methods: MR images of all VLBW infants scanned consecutively at term-equivalent age between April 2012 and May 2018 were retrospectively reviewed, and infants with PWMLs defined as small areas of high T1 and/or low T2 signal in the periventricular white matter were selected and included in the study. Each lesion was analyzed separately and characterized by localization, organization pattern, and distance from the lateral ventricle. Clinical data were retrieved from the department database. Results: A total of 517 PWMLs were registered in 81 patients, with 93 lesions (18%) visible on SWI (SWI+), revealing the presence of hemosiderin deposits. On univariate analysis, compared to SWI- PWML, SWI+ lesions were closer to the ventricle wall, more frequently organized in linear pattern and associated with lower birth weight, lower gestational age, lower admission temperature, need for intubation, bronchopulmonary dysplasia, retinopathy of prematurity, and presence of GMH-IVH. On multivariate analysis, closer distance to the ventricle wall on axial scan and lower birth weight were associated with visibility of PMWLs on SWI (p = 0.003 and p = 0.0001, respectively). Conclusions: Our results suggest a nosological difference between SWI+ and SWI- PWMLs. Other prospective studies are warranted to corroborate these observations.

Risk factors for pediatric cerebral sinovenous thrombosis: A case-control study with case validation

INTRODUCTION

Cerebral sinovenous thrombosis (CSVT) represents the second most common type of venous thromboembolism (VTE) in children. Current literature includes limited evidence on risk factors for CSVT, particularly in the pediatric population. We sought to determine risk factors for CSVT in pediatric patients through a single-institutional case-control study. In addition, we evaluated thrombophilias, treatments and outcomes in CSVT among cases.

METHODS

A case-control study was performed at Johns Hopkins All Children's Hospital on patients admitted from March 31, 2006 through April 1, 2018. Cases were identified using diagnostic codes and confirmed based on electronic health record (EHR) and neuroimaging review. Controls were matched in a 2:1 fashion accounting for the month and year of admission.

RESULTS

A total of 60 CSVT cases and 120 controls were identified. Median (range) age was 4.8 years (0-21.3 years) for cases and 5.6 years (0-20.0 years) for controls. Factors putatively associated with CSVT in unadjusted analyses were: corticosteroid use, presence of a central venous catheter, mechanical ventilation, systemic infection, head/neck infection, head/neck trauma, and chronic inflammatory disease. In the multivariable model, head/neck infection (OR: 13.8, 95% CI: 4.87-38.7; P < 0.01), head/neck trauma (OR: 12.7, 95% CI: 2.88-56.2; P < 0.01), and mechanical ventilation (OR: 9.32, 95% CI: 2.35-36.9; P = 0.01) remained independent, statistically-significant risk factors. 61% of patients were subacutely treated with anticoagulants and of those, only two developed relevant bleeding after initiation of therapy.

CONCLUSIONS

This single-institutional case-control study reveals that head/neck infection, head/neck trauma, and mechanical ventilation are independent risk factors for pediatric CSVT. These findings will be further investigated via a cooperative registry of pediatric hospital-acquired VTE, by which a risk model for pediatric CSVT will be developed and validated, in order to inform future preventive strategies in at-risk pediatric patients.

Cranial ultrasound findings in preterm germinal matrix haemorrhage, sequelae and outcome

Germinal matrix-intraventricular haemorrhage (GMH-IVH), periventricular haemorrhagic infarction (PHI) and its complication, post-haemorrhagic ventricular dilatation (PHVD), are still common neonatal morbidities in preterm infants that are highly associated with adverse neurodevelopmental outcome. Typical cranial ultrasound (CUS) findings of GMH-IVH, PHI and PHVD, their anatomical substrates and underlying mechanisms are discussed in this paper. Furthermore, we propose a detailed descriptive classification of GMH-IVH and PHI that may improve quality of CUS reporting and prediction of outcome in infants suffering from GMH-IVH/PHI.

Perinatal thalamic injury: MRI predictors of electrical status epilepticus in sleep and long-term neurodevelopment

•

The majority of patients with perinatal thalamic injury, will develop epilepsy with ESES after the age of two years.

•

ESES is associated with neurodevelopmental deficits.

•

Larger residual thalamic volume at the three months MRI correlates to higher total IQ/DQ during follow-up.

•

MRI at three months appears to be useful to predict neurodevelopmental outcome in this population.

Objective

Perinatal thalamic injury is associated with epilepsy with electrical status epilepticus in sleep (ESES). The aim of this study was to prospectively quantify the risk of ESES and to assess neuroimaging predictors of neurodevelopment.

Methods

We included patients with perinatal thalamic injury. MRI scans were obtained in the neonatal period, around three months of age and during childhood. Thalamic and total brain volumes were obtained from the three months MRI. Diffusion characteristics were assessed. Sleep EEGs distinguished patients into ESES (spike-wave index (SWI) >85%), ESES-spectrum (SWI 50–85%) or no ESES (SWI < 50%). Serial Intelligence Quotient (IQ)/Developmental Quotient (DQ) scores were obtained during follow-up. Imaging and EEG findings were correlated to neurodevelopmental outcome.

Results

Thirty patients were included. Mean thalamic volume at three months was 8.11 (±1.67) ml and mean total brain volume 526.45 (±88.99) ml. In the prospective cohort (n = 23) 19 patients (83%) developed ESES (-spectrum) abnormalities after a mean follow-up of 96 months. In the univariate analysis, larger thalamic volume, larger total brain volume and lower SWI correlated with higher mean IQ/DQ after 2 years (Pearson's r = 0.74, p = 0.001; Pearson's r = 0.64, p = 0.005; and Spearman's rho -0.44, p = 0.03). In a multivariable mixed model analysis, thalamic volume was a significant predictor of IQ/DQ (coefficient 9.60 [p < 0.001], i.e., corrected for total brain volume and SWI and accounting for repeated measures within patients, a 1 ml higher thalamic volume was associated with a 9.6 points higher IQ). Diffusion characteristics during childhood correlated with IQ/DQ after 2 years.

Significance

Perinatal thalamic injury is followed by electrical status epilepticus in sleep in the majority of patients. Thalamic volume and diffusion characteristics correlate to neurodevelopmental outcome.

The Role of Factor V Leiden, Prothrombin G20210A, and MTHFR C677T Mutations in Neonatal Cerebral Sinovenous Thrombosis

Little is known about the pathogenesis of cerebral sinovenous thrombosis (CSVT) in the neonate. Although thrombophilia has been described as increasing the risk of CSVT in adults, it remains controversial in pediatric patients, and prospective case–control studies regarding neonatal CSVT are lacking. From 2008 to 2017, all 26 consecutive newborn infants ≥35 weeks of gestation diagnosed with neonatal CSVT, and their mothers, were tested for factor V Leiden (FV) G1691A, FII G20210A, and methylenetetrahydrofolate reductase C677T (MTHFR C677T) mutations. Eighty-five mother–infant pairs were recruited as controls. All infants except 1 with CSVT were suspected due to clinical symptoms, mainly seizures (22/25). Magnetic resonance imaging was performed in 24/26 infants. Heterozygous FV G1691A, FII G20210A, and homozygous MTHFR C677T mutations were present in 1/26, 3/26, and 3/20 infants with CSVT, respectively. FII (odds ratio: 10.96; 95% confidence interval [CI]: 1.09-110.35) and male sex (3.93; 95% CI: 1.43-10.76) were associated with CSVT. When FII G20210A analysis was adjusted for sex, the OR for FII G20210A was 6.70 (95% CI: 0.65-69.22). No differences were found for FV G1691A or homozygous MTHFR mutations between neonates with CSVT and their mothers, compared to controls.

Neonatal cerebral sinovenous thrombosis

Cerebral sinovenous thrombosis (CSVT) is a focal or diffuse disruption of cerebral blood flow secondary to occlusion of cerebral veins and/or sinuses. The challenge of CSVT during the neonatal age has led to a great interest in this condition among neonatologists, child neurologists, and pediatric neuroradiologists. The highly variable clinical spectra, etiologies, and prognosis require fine medical skills and a high level of suspicion. Nevertheless, the diagnosis is often delayed or missed altogether. Differences in brain vulnerability at different stages of maturation may explain the spectrum of associated brain lesions, which varies with gestational age. Treatment is controversial and reported clinical outcomes vary widely. The controversial treatment of CSVT with anticoagulant therapy is based only on case series and expert consensus, there is lack of safety data.

Differences in subependymal vein anatomy may predispose preterm infants to GMH-IVH

BACKGROUND AND PURPOSE

The anatomy of the deep venous system plays an important role in the pathogenesis of brain lesions in the preterm brain as shown by different histological studies. The aims of this study were to compare the subependymal vein anatomy of preterm neonates with germinal matrix haemorrhage-intraventricular haemorrhage (GMH-IVH), as evaluated by susceptibility-weighted imaging (SWI) venography, with a group of age-matched controls with normal brain MRI, and to explore the relationship between the anatomical features of subependymal veins and clinical risk factors for GMH-IVH.

METHODS

SWI venographies of 48 neonates with GMH-IVH and 130 neonates with normal brain MRI were retrospectively evaluated. Subependymal vein anatomy was classified into six different patterns: type 1 represented the classic pattern and types 2-6 were considered anatomic variants. A quantitative analysis of the venous curvature index was performed. Variables were analysed by using Mann-Whitney U and χ² tests, and a multiple logistic regression analysis was performed to evaluate the association between anatomical features, clinical factors and GMH-IVH.

RESULTS

A significant difference was noticed among the six anatomical patterns according to the presence of GMH-IVH (χ²=14.242, p=0.014). Anatomic variants were observed with higher frequency in neonates with GMH-IVH than in controls (62.2% and 49.6%, respectively). Neonates with GMH-IVH presented a narrower curvature of the terminal portion of subependymal veins (p<0.05). These anatomical features were significantly associated with GMH-IVH (p<0.05).

CONCLUSION

Preterm neonates with GMH-IVH show higher variability of subependymal veins anatomy confirming a potential role as predisposing factor for GMH-IVH.

Clinical and neuroimaging characteristics of cerebral sinovenous thrombosis in neonates undergoing cardiac surgery

OBJECTIVES

Neonates with congenital heart disease may have an increased risk of cerebral sinovenous thrombosis, but incidence rates are lacking. This study describes the clinical and neuroimaging characteristics of cerebral sinovenous thrombosis in neonates undergoing cardiac surgery.

METHODS

Forty neonates (78% male) requiring neonatal univentricular or biventricular cardiac repair using cardiopulmonary bypass were included. All underwent preoperative (median postnatal day 7) and postoperative (median postoperative day 7) magnetic resonance imaging of the brain, including venography, to detect cerebral sinovenous thrombosis. Clinical characteristics were compared between cerebral sinovenous thrombosis positive and cerebral sinovenous thrombosis negative neonates.

RESULTS

Postoperatively, cerebral sinovenous thrombosis was diagnosed in 11 neonates (28%), with the transverse sinus affected in all, and involvement of multiple sinuses in 10 (91%). Preoperatively, signs of thrombosis were seen in 3 cases (8%). Focal infarction of the basal ganglia was significantly more common in cerebral sinovenous thrombosis positive than cerebral sinovenous thrombosis negative neonates (P = .025). Cerebral sinovenous thrombosis positive neonates spent more time in the intensive care unit preoperatively (P = .001), had lower weight (P = .024) and lower postmenstrual age (P = .030) at surgery, and had prolonged use of a central venous catheter (P = .023) and a catheter placed in the internal jugular vein more often (P = .039). Surgical and postoperative factors were not different between new postoperative cerebral sinovenous thrombosis positive and cerebral sinovenous thrombosis negative neonates.

CONCLUSIONS

Cerebral sinovenous thrombosis might be more common than previously understood in neonates undergoing cardiac surgery. In our study, cerebral sinovenous thrombosis was associated with a higher risk of additional intra-parenchymal brain injury.

MR imaging for accurate prediction of outcome after perinatal arterial ischemic stroke: Sooner not necessarily better

BACKGROUND

Involvement of the corticospinal tracts after perinatal arterial ischemic stroke (PAIS) is strongly correlated with adverse motor outcome.

METHODS

Two full-term infants with PAIS, with two early MRI scans available, are reported.

RESULTS

Diffusion weighted imaging (DWI)-MRI, performed within 24 h following onset of seizures and repeated 48 h later, clearly showed restricted diffusion within the middle cerebral artery territory on both MRIs, but clear patterns of signal intensity changes in the descending corticospinal tracts on the second MRI only.

CONCLUSION

Since involvement of the corticospinal tracts is essential for prediction of motor outcome, we may need to reconsider optimal timing of MR imaging for prediction of neurodevelopmental outcome after PAIS.

Heparin for the treatment of thrombosis in neonates

BACKGROUND

Among pediatric patients, newborns are at highest risk of developing thromboembolism. Neonatal thromboembolic (TE) events may consist of both venous and arterial thromboses and often iatrogenic complications (eg, central catheterization). Treatment guidelines for pediatric patients with TE events most often are extrapolated from the literature regarding adults. Options for the management of neonatal TE events include expectant management; nitroglycerin ointment; thrombolytic therapy or anticoagulant therapy, or a combination of the two; and surgery. Since the 1990s, low molecular weight heparin (LMWH) has become the neonatal anticoagulant of choice. Reasons for its appeal include predictable dose response, no need for venous access, and limited monitoring requirements. The overall major complication rate is around 5%. Whether preterm infants are at increased risk is unclear. No data are available on the frequency of osteoporosis, heparin-induced thrombocytopenia (HIT), or other hypersensitivity reactions in children and neonates exposed to LMWH.

OBJECTIVES

To assess whether heparin treatment (both unfractionated heparin [UFH] and LMWH) reduces mortality and morbidity rates in preterm and term newborn infants with diagnosed thrombosis. The intervention is compared with placebo or no treatment. Also, to assess the safety of heparin therapy (both UFH and LMWH) for potential harms.Subgroup analyses were planned to examine gestational age, birth weight, mode of thrombus diagnosis, presence of a central line, positive family history for genetic disorders (thrombophilia, deficiency of protein S and protein C, methylenetetrahydrofolate reductase [MTHFR] mutation), route of heparin administration, type of heparin used, and location of thrombus (see "Subgroup analysis and investigation of heterogeneity").

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 4), MEDLINE via PubMed (1966 to May 9, 2016), Embase (1980 to May 9, 2016), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to May 9, 2016). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials.

SELECTION CRITERIA

Randomized, quasi-randomized, and cluster-randomized controlled trials comparing heparin versus placebo or no treatment in preterm and term neonates with a diagnosis of thrombosis.

DATA COLLECTION AND ANALYSIS

We used the standard methods of the Cochrane Neonatal Review Group. Two review authors independently assessed studies identified by the search strategy for inclusion.

MAIN RESULTS

Our search strategy yielded 1160 references. Two review authors independently assessed all references for inclusion. We found no completed studies and no ongoing trials for inclusion.

AUTHORS' CONCLUSIONS

We found no studies that met our inclusion criteria and no evidence from randomized controlled trials to recommend or refute the use of heparin for treatment of neonates with thrombosis.

MRI Based Preterm White Matter Injury Classification: The Importance of Sequential Imaging in Determining Severity of Injury

Background

The evolution of non-hemorrhagic white matter injury (WMI) based on sequential magnetic resonance imaging (MRI) has not been well studied. Our aim was to describe sequential MRI findings in preterm infants with non-hemorrhagic WMI and to develop an MRI classification system for preterm WMI based on these findings.

Methods

Eighty-two preterm infants (gestation ≤35 weeks) were retrospectively included. WMI was diagnosed and classified based on sequential cranial ultrasound (cUS) and confirmed on MRI.

Results

138 MRIs were obtained at three time-points: early (<2 weeks; n = 32), mid (2–6 weeks; n = 30) and term equivalent age (TEA; n = 76). 63 infants (77%) had 2 MRIs during the neonatal period. WMI was non-cystic in 35 and cystic in 47 infants. In infants with cystic-WMI early MRI showed extensive restricted diffusion abnormalities, cysts were already present in 3 infants; mid MRI showed focal or extensive cysts, without acute diffusion changes. A significant reduction in the size and/or extent of the cysts was observed in 32% of the infants between early/mid and TEA MRI. In 4/9 infants previously seen focal cysts were no longer identified at TEA. All infants with cystic WMI showed ≥2 additional findings at TEA: significant reduction in WM volume, mild-moderate irregular ventriculomegaly, several areas of increased signal intensity on T1-weighted-images, abnormal myelination of the PLIC, small thalami.

Conclusion

In infants with extensive WM cysts at 2–6 weeks, cysts may be reduced in number or may even no longer be seen at TEA. A single MRI at TEA, without taking sequential cUS data and pre-TEA MRI findings into account, may underestimate the extent of WMI; based on these results we propose a new MRI classification for preterm non-hemorrhagic WMI.

Heparin for the prevention of intraventricular haemorrhage in preterm infants

BACKGROUND

Preterm birth remains the major risk factor for the development of intraventricular haemorrhage, an injury that occurs in 25% of very low birth weight infants. Intraventricular haemorrhage is thought to be venous in origin and intrinsic thromboses in the germinal matrix are likely to play a triggering role. Heparin activates antithrombin and promotes the inactivation of thrombin and other target proteinases. The administration of anticoagulants such as heparin may offset the increased risk of developing intraventricular haemorrhage and may also reduce the risk of developing parenchymal venous infarct, a condition known to complicate intraventricular haemorrhage.

OBJECTIVES

To assess whether the prophylactic administration of heparin reduces the incidence of germinal matrix-intraventricular haemorrhage in very preterm neonates when compared to placebo, no treatment, or other anticoagulants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2015), MEDLINE (1996 to 22 November 2015), EMBASE (1980 to 22 November 2015) and CINAHL (1982 to 22 November 2015), applying no language restrictions. We searched the abstracts of the major congresses in the field (Perinatal Society of Australia and New Zealand and Pediatric Academic Societies) from 2000 to 2015.

SELECTION CRITERIA

Randomised controlled trials, quasi-randomised controlled trials and cluster trials comparing the administration of early, i.e. within the first 24 hours of life, heparin in very preterm infants (gestational age < 32 weeks).

DATA COLLECTION AND ANALYSIS

For each of the included trials, two authors independently extracted data (e.g. number of participants, birth weight, gestational age, dose of heparin, mode of administration, and duration of therapy, etc.) and assessed the risk of bias (e.g. adequacy of randomisation, blinding, completeness of follow up). The primary outcomes considered in this review are intraventricular haemorrhage, severe intraventricular haemorrhage and neonatal mortality.

MAIN RESULTS

Two randomised controlled trials enrolling a total of 155 infants met the inclusion criteria of this review. Both trials compared low-dose heparin to the same solution without heparin in very preterm newborns requiring umbilical catheterisation. No trials were identified that specifically studied the use of heparin in infants at risk of germinal matrix-intraventricular haemorrhage.We found no differences in the rates of intraventricular haemorrhage (typical RR 0.93, 95% CI 0.61 to 1.41; typical RD -0.03, 95% CI -0.17 to 0.12; 2 studies, 155 infants; I² = 57% for RR and I² = 65% for RD), severe intraventricular haemorrhage (typical RR 1.01, 95% CI 0.46 to 2.23; typical RD 0.00, 95% CI -0.11 to 0.11; 2 studies, 155 infants; I² = 0% for RR and I² = 0% for RD) and neonatal mortality (typical RR 0.69, 95% CI 0.28 to 1.67; typical RD -0.04, 95% CI -0.14 to 0.06; 2 studies, 155 infants; I² = 28% for RR and I² = 50% for RD). We judged the quality of the evidence supporting these findings as very low (rates of intraventricular haemorrhage) and low (severe intraventricular haemorrhage and neonatal mortality) mainly because of limitations in the study designs and the imprecision of estimates. We found very few data on other relevant outcomes, such as bronchopulmonary dysplasia, pulmonary haemorrhage and patent ductus arteriosus; and no study assessing long-term outcomes (e.g. neurodevelopmental disability).

AUTHORS' CONCLUSIONS

There is very limited data on the effect of prophylactic administration of heparin on the incidence and severity of IVH in very preterm neonates. Both the identified trials used heparin in the context of maintaining umbilical line patency and not specifically as an agent to prevent germinal matrix-intraventricular haemorrhage. Given the imprecision of our estimates, the results of this systematic review are consistent with either a benefit or a detrimental effect of heparin and do not provide a definitive answer to the review question. Limited evidence is available on other clinically relevant outcomes.

Radiological and clinical features of cerebral sinovenous thrombosis in newborns and older children

BACKGROUND AND PURPOSE

Cerebral sinovenous thrombosis (CSVT) represents an increasingly recognized cause of pediatric stroke. Our purpose was to assess gender and age differences in the etiology, clinical presentation, and imaging features of CSVT in neonates and older children.

METHODS

Subjects aged newborn to 18 years diagnosed with CSVT at the Lille university hospital between 2011 and 2014 were included.

RESULTS

Eleven neonates and 16 non-neonates constituted the study population. The incidence of CSVT was significantly higher in male newborns. Clinical presentation did not vary significantly between the groups. Risk factors were age-dependent, with acute systemic illnesses significantly predominating in neonates (54%), whereas local infections, prothrombotic conditions, and trauma were more common in older children (36, 27, and 27% respectively). No predisposing factor could be identified in 36% of the neonates as compared to less than 5% of the non-neonates. Thrombosis of the deep venous structures was documented in 73% of the neonates whereas involvement of the superficial sinuses was significantly more frequent in the non-neonates group. Venous infarctions and extraparenchymal hemorrhages were significantly more frequent in the neonates group.

CONCLUSION

Male patients are at higher risk for CSVT than females. In neonates, involvement of the deep venous structures is significantly more common. Brain parenchymal and extraparenchymal changes occur more frequently in this age group than in older children.

Perinatal thrombosis: implications for mothers and neonates

Stroke is more likely to occur in the perinatal period than any other time in childhood, and these events can lead to a lifetime of intellectual and motor disabilities, epilepsy, and behavioral challenges. This review describes the epidemiology and natural history of perinatal arterial ischemic stroke (PAIS) and cerebral sinovenous thrombosis (CSVT), risk factors for these complications, recent evidence regarding treatment strategies, and current gaps in knowledge. Existing evidence demonstrates the multifactorial etiology of symptomatic ischemic stroke in neonates, which includes a combination of maternal, delivery, and neonatal factors. The importance of inherited thrombophilia in the pathophysiology and long-term outcomes of perinatal stroke requires additional study. At this time, there is no evidence to support routine extensive thrombophilia screening outside of a research setting. Despite the frequency of perinatal stroke and its association with substantial morbidity, treatment strategies are currently limited, and prevention strategies are nonexistent. Anticoagulation is rarely indicated in PAIS, and more work needs to focus on neuroprotective prevention and alternate treatment strategies. Anticoagulation does appear to be safe in CSVT and may prevent thrombus progression but clinical equipoise remains, and clinical trials are needed to obtain evidence regarding short- and long-term efficacy outcomes.

Neonatal deep white matter venous infarction and liquefaction: a pseudo-abscess lesion

BACKGROUND

Deep white matter hemorrhagic venous infarction with subsequent cavitation due to necrosis and liquefaction has been described in neonates and may be associated with infection and meningitis. In our experience, the MRI pattern of these lesions is confused with the pattern seen with cerebral abscesses.

OBJECTIVE

The purpose of our study was to characterize the MRI findings of post infarction necrosis and liquefaction after hemorrhagic deep white matter venous infarction in infants and to distinguish these lesions from cerebral abscesses.

MATERIALS AND METHODS

An institutional review board approved a retrospective review of imaging records to identify all patients with cerebral venous infarction at a children's hospital during a 10-year period. Nine infants had deep white matter hemorrhagic venous infarction with white matter fluid signal cavitary lesions. A diagnosis of cerebral abscess was considered in all. The imaging and laboratory findings in these patients are reviewed and compared to descriptions of abscesses found in the literature.

RESULTS

There were six female and three male infants. The mean age at presentation was 20 days (range: 0-90 days), while the corrected age at presentation was less than 30 days for all patients. Seven patients presented with seizures and signs of infection; one infant presented with lethargy and later proved to have protein C deficiency. MRI was performed 0-12 days from presentation in these eight patients. Another patient with known protein C deficiency underwent MRI at 30 days for follow-up of screening US abnormalities. There were a total of 38 deep cerebral white matter fluid signal cavitary lesions: 25 frontal, 9 parietal, 2 temporal, 2 occipital. Larger lesions had dependent debris. All lesions had associated hemorrhage and many lesions had evidence of adjacent small vessel venous thrombosis. Lesions imaged after gadolinium showed peripheral enhancement. Three lesions increased in size on follow-up imaging. Three patients, two with meningitis confirmed via microbiology and one with presumed meningitis by CSF counts, underwent surgical aspiration of a total of six lesions. All specimens were sent for pathology and culture and were negative for microorganisms.

CONCLUSION

Recognizing the MR appearance of cavitary necrosis and liquefaction after deep white matter cerebral venous infarction in neonates can distinguish this entity from cerebral abscess and potentially avoid an unnecessary neurosurgical aspiration procedure.

Treatment of Complicated Spontaneous Twin Anemia-Polycythemia Sequence via Fetoscopic Laser Ablation of the Vascular Communications

Monochorionic diamniotic twins share a single placenta and have intertwin vascular communications that link the circulatory systems of the twins together. Twin anemia-polycythemia sequence (TAPS) is an atypical form of twin-twin transfusion syndrome (TTTS) caused by net transfer of blood from one fetus to the other and is characterized by large intertwin hemoglobin differences in the absence of oligohydramnios and polyhydramnios. This condition may develop spontaneously (sTAPS) or as a result of residual vascular communications after prior laser surgery. Because of the relatively low prevalence and lack of clinical awareness, the natural history of sTAPS is unclear and the antenatal treatment remains controversial. Case series of sTAPS have described expectant management with timed delivery, intrauterine blood transfusion, and fetoscopic laser treatment. Favorable outcomes have been described in cases of uncomplicated sTAPS that underwent conservative measures. However, we believe that there may be a subgroup of high-risk or complicated sTAPS patients that may benefit from definitive treatment afforded by fetoscopic laser therapy. We describe 3 complicated cases of sTAPS successfully treated with selective laser photocoagulation of communicating vessels. In 2 of the cases, placental pathology identified thrombosed fetal vessels of the polycythemic twin.

Neonatal stroke: a review of the current evidence on epidemiology, pathogenesis, diagnostics and therapeutic options

Neonatal stroke, including perinatal arterial ischaemic stroke and cerebral sinovenous thrombosis, remains a serious problem in the neonate. This article reviews the current evidence on epidemiology, pathogenesis, diagnostics and therapeutic options.

CONCLUSION

Although our understanding of the underlying mechanisms and possible risk factors has improved, little progress has been made towards therapeutic options. Considering the high incidence of neurological sequelae, the need for therapeutic options is high and should be the focus of future research.

Severe cerebral injury in a recipient with twin anemia-polycythemia sequence

Twin anemia-polycythemia sequence (TAPS) results from slow intertwin blood transfusion through minuscule placental vascular anastomoses and is characterized by large intertwin hemoglobin differences in the absence of amniotic fluid discordance. The optimal management of TAPS is not clear. We report a case of TAPS detected antenatally by Doppler ultrasound examination at 15 + 6 weeks' gestation. After counseling, the parents opted for expectant management. Regular Doppler measurements were performed and these remained fairly stable. An emergency Cesarean section was performed at 34 + 5 weeks following signs of fetal distress. The donor twin was severely anemic while the recipient twin had severe polycythemia-hyperviscosity syndrome. On day 1, the recipient developed respiratory insufficiency and subclinical status epilepticus. Magnetic resonance imaging showed a total loss of gray-white matter differentiation as a sign of severe diffuse cerebral ischemia and bilateral intra- and extra-axial hemorrhages. There was almost complete lack of arterial and venous cerebral blood flow. On day 3 intensive care treatment was withdrawn in view of the severity of the brain injury. This case report demonstrates that TAPS may lead to severe cerebral injury and fatal outcome in the recipient twin, and highlights the importance of antenatal Doppler ultrasound monitoring and choice of management.

Neonatal thalamic hemorrhage is strongly associated with electrical status epilepticus in slow wave sleep

PURPOSE

Thalamic hemorrhage has been associated with neonatal cerebral sinovenous thrombosis (CSVT), especially when the straight sinus is involved, and often presents with neonatal seizures. Early thalamic injury has previously been shown to predispose to epilepsy and electrical status epilepticus in slow wave sleep (ESES). The objective of this study was to assess the prevalence of sleep-induced epileptic electroencephalography (EEG) abnormalities and postneonatal epilepsy after neonatal thalamic hemorrhage associated with CSVT, in the absence of more widespread cerebral damage.

METHODS

Between 2003 and 2008 15 neonates were diagnosed with a thalamic hemorrhage due to suspected or proven CSVT. Neurodevelopment and the history of seizures were assessed at follow-up in the outpatient clinic in all 14 survivors (age 2-9 years). Whole-night or sleep-deprived EEG recordings were obtained to assess the prevalence of interictal epileptiform activity (EA) and calculate a sleep-induced spike and wave index (SWI).

KEY FINDINGS

Three children were diagnosed with classic ESES (SWI >85%). Two children had ESES spectrum disorder (SWI between 50% and 85%), and in two children significant sleep-induced epileptiform activity (SIEA) was noted (SWI between 25% and 50%). Two other children were diagnosed with focal epilepsy, in the absence of sleep-induced epileptiform EEG abnormalities. Five children (age 2-7 years) had normal EEG recordings at follow-up. Deficits in neurodevelopment were seen significantly more often in children with ESES, ESES spectrum, or SIEA.

SIGNIFICANCE

Neonates with thalamic hemorrhage associated with straight sinus thrombosis, without evidence of more widespread cerebral damage, are at high risk of developing ESES (spectrum) disorder (35%), SIEA (14%), or focal epilepsy (14%). Electrographic abnormalities may already be present prior to recognition of cognitive deficits. Early diagnosis may guide parents and caregivers, and subsequent treatment may improve neurodevelopmental outcome. Routine annual sleep EEG recordings in children with neonatal thalamic injury following CSVT may improve recognition of ESES.

EPNS/SFNP guideline on the anticoagulant treatment of cerebral sinovenous thrombosis in children and neonates

Anticoagulation of cerebral sinovenous thrombosis (CSVT) is recommended in adults and has been also approved in the paediatric setting. Some controversies remain however between the existing paediatric professional consensus, notably about its use in children with intra-cranial haemorrhage and in neonates. The publication of further original studies prompted the French Society for Paediatric Neurology (SFNP) in association with a panel of EPNS experts, to update the level of evidence and the knowledge in this domain. A bibliographic analysis revealed that anticoagulants are widely used in paediatrics. Anticoagulation is well tolerated by children (Class I, level of evidence B) and also probably by neonates (Class IIa, level of evidence B). During the acute phase, anticoagulation is probably effective in reducing the risk of death and sequelae in children (Class IIa, level of evidence B). It is not yet possible to draw any conclusions regarding neonates (Class IIb). Anticoagulation is also effective in reducing the risk of recurrence (Class I, level of evidence B). This risk is dependent on several individual factors such as the age of the child, the cause of the thrombosis, the persistence or the recurrence of thrombogenic factors, and the speed of sinus recanalisation. The duration of anticoagulation needs therefore to be individually tailored (Class I, level of evidence B). These observations have led to the following recommendations: -In the absence of any contraindication, it is reasonable to initiate anticoagulation during the acute phase of CSVT in children. Prolonged treatment over 3-6 months is justified according to individual factors. -In the absence of any contraindication, anticoagulation may be considered individually during the acute phase of CSVT in neonates for a duration of 6-12 weeks.

Neonatal cerebral sinovenous thrombosis: neuroimaging and long-term follow-up

Neonates are known to have a higher risk of cerebral sinovenous thrombosis than children of other age groups. The exact incidence in neonates remains unknown and is likely to be underestimated, as clinical presentation is nonspecific and diagnosis can only be made when dedicated neuroimaging techniques, including computed tomographic venography or magnetic resonance venography, are performed. Associated intracranial lesions are common and some, such as a unilateral thalamic hemorrhage, should suggest cerebral sinovenous thrombosis as the underlying etiology. Neurodevelopmental outcome is poor in approximately 50% of these infants and is adversely affected by associated parenchymal lesions. Anticoagulation therapy will limit propagation of the clot and possibly the development or enhancement of parenchymal lesions. Multicenter randomized clinical trials are urgently needed to address many of these important issues.