Neonatal cerebral sinovenous thrombosis

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 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.

Incidence and risk factors of cerebral sinovenous thrombosis in infants

AIM

To describe the incidence of term and preterm neonatal cerebral sinovenous thrombosis (CSVT) and identify perinatal risk factors.

METHOD

This was a national capture-recapture calculation-corrected surveillance and nested case-control study. Infants born preterm and at term with magnetic resonance imaging-confirmed neonatal CSVT were identified by surveillance in all paediatric hospitals in Germany (2015-2017). Incidence was corrected for underreporting using a capture-recapture method in one federal state and then extrapolated nationwide. We reviewed PubMed for comparisons with previously reported incidence estimators. We used a population-based perinatal database for quality assurance to select four controls per case and applied univariate and multivariable regression for risk factor analysis.

RESULTS

Fifty-one newborn infants (34 males, 17 females; 14 born preterm) with neonatal CSVT were reported in the 3-year period. The incidence of term and preterm neonatal CSVT was 6.6 (95% confidence interval [CI] 4.4-8.7) per 100 000 live births. Median age at time of confirmation of the diagnosis was 9.95 days (range 0-39d). In the univariate analysis, male sex, preterm birth, hypoxia and related indicators (umbilical artery pH <7.1; 5-minute Apgar score <7; intubation/mask ventilation; perinatal asphyxia), operative vaginal delivery, emergency Caesarean section, and pathological fetal Doppler sonography were associated (p<0.05) with neonatal CSVT. Multivariable regression yielded hypoxia (odds ratio=20.3; 95% CI 8.1-50.8) as the independent risk factor.

INTERPRETATION

Incidence of neonatal CSVT was within the range of other population-based studies. The results suggest that hypoxia is an important perinatal risk factor for the aetiology of neonatal CSVT.

Deep Medullary Vein White Matter Injury Global Severity Score Predicts Neurodevelopmental Impairment

AIM

To examine associations between the deep medullary vein white matter injury global severity scoring system and neurodevelopmental impairment.

METHODS

This is a prospective observational cohort study of infants born at ≥32 weeks, diagnosed with deep medullary vein thrombosis and infarction on neuroimaging in the first month of life. Developmental testing was performed using validated measures for early, preschool, and school-age follow-up.

RESULTS

Nineteen (37%) patients had major neurodevelopmental impairment. Global severity score was higher among patients with neurodevelopmental impairment (21.6 vs 13.4, P = .04). Overall, 78% of patients with epilepsy had neurodevelopmental impairment. A greater degree of asymmetry with right-sided injury predominance was associated with lower Bayley-III cognitive scores and presence of neurodevelopmental impairment (P < .01).

CONCLUSIONS

Results suggest a need for targeted clinical surveillance for patients with a high global severity score and/or asymmetric, predominantly right cerebral white matter injury and for those who develop epilepsy.

Clinical Diversity of Cerebral Sinovenous Thrombosis and Arterial Ischaemic Stroke in the Neonate: A Surveillance Study

INTRODUCTION

Incidence, risk factors, clinical presentation, onset of symptoms, and age at diagnosis differ between neonatal arterial ischaemic stroke (AIS) and cerebral sinovenous thrombosis (CSVT). A more accurate and earlier discrimination of these two entities can be of eminent importance.

METHODS

Active surveillance for AIS and CSVT was performed in 345 German paediatric hospitals. Only MRI confirmed cases were included in our analysis. Patients with AIS were compared to CSVT cases with regard to age at diagnosis, pattern of clinical symptoms, and case characteristics.

RESULTS

Data on 144 AIS and 51 CSVT neonatal cases were collected from 2015 to 2017. The frequency of reported AIS cases was 2.8 [95% CI 2.1; 3.9] times higher compared to reported CSVT cases. CSVT patients were more likely to be born premature (CSVT 14/48, 29.2%; AIS 19/140, 13.2%; p = 0.02) and to have signs of perinatal acidosis (30.2% CSVT vs. 13.5% AIS; p = 0.01). Generalized seizures and lethargy were more likely to occur in infants with CSVT (p < 0.0001). Age at onset of symptoms and at time of diagnosis were shifted to older ages in CSVT (p < 0.0001).

DISCUSSION/CONCLUSION

In the neonatal period, AIS is about three times more common than CSVT. A higher proportion of critically ill infants in CSVT and a later onset of symptoms may indicate that perinatal and postnatal complications are more important for CSVT than for AIS.

Sonographic Diagnosis of Neonatal Cerebral Venous Sinus Thrombosis

Cerebral venous thrombosis (CVT) is an uncommon but fatal disease in the pediatric age group, with a neonatal preponderance. The clinical presentation is nonspecific. Within the first 48 hours, the neonate usually presents with nonspecific signs such as respiratory distress, poor tone, and asphyxia. Neurological signs such as seizures, lethargy, apnea, and poor feeding set in later. We present the case of a neonatal CVT, presenting as asphyxia and respiratory depression on day 1 of life. CVT was diagnosed on neonatal cranial ultrasound. The patient died 3 days later.

An Important Finding of White Matter Injury in Late Preterm Infant: Deep Medullary Vein Involvement

Objective: To investigate high risk factors and magnetic resonance imaging (MRI) features in late preterm infants with severe white matter injury (WMI) associated with abnormal deep medullary veins (DMVs). Materials and Methods: Preterm infants with severe WMI, who were hospitalized in Shengjing Hospital from 1st January 2009 to 31st December 2018, were enrolled in this retrospective study. High risk factors and MRI characteristics of infants with abnormal DMVs were analyzed and compared with those of infants without DMV abnormalities. Results: A total of 2032 late preterm infants were examined by MRI; 71 cases (3.5%) had severe WMI and 15 of these (21.1%) had abnormal DMVs. The incidence of maternal diabetes was higher in infants with abnormal DMVs and neonatal convulsions were more likely (P < 0.05). The incidence of grade IV injury (P < 0.05), white matter periventricular cysts and thalamic injury (P < 0.01), cerebral venous sinus thrombus (P < 0.01) and germinal matrix/intraventricular hemorrhage (P < 0.05) were higher in infants with abnormal DMVs than in infants with normal DMVs. Conclusions: Congestion/thrombosis of DMVs may be an important cause of severe WMI in late preterm infants, especially in periventricular leukomalacia-like WMI. WMI with abnormal DMVs is more likely to lead to thalamic injury.

Perinatal stroke syndromes: Similarities and diversities in aetiology, outcome and management

With a birth-prevalence of 37-67/100,000 (mostly term-born), perinatal stroke encompasses distinct disease-states with diverse causality, mechanism, time of onset, mode of presentation and outcome. Neonatal primary haemorrhagic stroke and ischemic events (also divided into neonatal arterial ischemic stroke and neonatal cerebral sinus venous thrombosis) that manifest soon after birth are distinguished from presumed perinatal - ischemic or haemorrhagic - stroke. Signs of the latter become apparent only beyond the neonatal period, most often with motor asymmetry or milestones delay, and occasionally with seizures. Acute or remote MRI defines the type of stroke and is useful for prognosis. Acute care relies on homeostatic maintenance. Seizures are often self-limited and anticonvulsant agents might be discontinued before discharge. Prolonged anticoagulation for a few weeks is an option in some cases of sinovenous thrombosis. Although the risk of severe impairment is low, many children develop mild to moderate multimodal developmental issues that require a multidisciplinary approach.

The pathology and aetiology of subcortical clefts in infants

In infants, traumatic surface contusions of the brain are rare but subcortical clefts or cysts, variously labelled "contusional tears", "contusional clefts", "cortical tears" or "parenchymal lacerations" have been ascribed to trauma, and are even said to be characteristic of shaking and abuse. We describe the pathology of subcortical clefts or haemorrhages in seven infants. In none were the axonal swellings characteristic of traumatic axonal injury seen in relation to the clefts. Subpial bleeding was associated with clefts in all the cases of recent onset. We hypothesize that subcortical clefts are not due to direct mechanical forces of trauma but are part of a secondary cascade caused by impaired venous drainage which may or may not follow trauma. The finding of subcortical and subpial haemorrhages should prompt a search for CVT. We consider the term "contusion" is not accurate and is misleading.

Diffuse optical tomography for the detection of perinatal stroke at the cot side: a pilot study

BACKGROUND

Perinatal stroke is a potentially debilitating injury, often under-diagnosed in the neonatal period. We conducted a pilot study investigating the role of the portable, non-invasive brain monitoring technique, diffuse optical tomography (DOT), as an early detection tool for infants with perinatal stroke.

METHODS

Four stroke-affected infants were scanned with a DOT system within the first 3 days of life and compared to four healthy control subjects. Spectral power, correlation, and phase lag between interhemispheric low frequency (0.0055-0.3 Hz) hemoglobin signals were assessed. Optical data analyses were conducted with and without magnetic resonance imaging (MRI)-guided stroke localization to assess the efficacy of DOT when used without stroke anatomical information.

RESULTS

Interhemispheric correlations of both oxyhemoglobin and deoxyhemoglobin concentration were significantly reduced in the stroke-affected group within the very low (0.0055-0.0095 Hz) and resting state (0.01-0.08 Hz) frequencies (p < 0.003). There were no interhemispheric differences for spectral power. These results were observed even without MRI stroke localization.

CONCLUSION

This suggests that DOT and correlation-based analyses in the low-frequency range can potentially aid the early detection of perinatal stroke, prior to MRI acquisition. Additional methodological advances are required to increase the sensitivity and specificity of this technique.

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.

Intracranial hemorrhage in neonates: A review of etiologies, patterns and predicted clinical outcomes

Intracranial hemorrhage (ICH) in neonates often results in devastating neurodevelopmental outcomes as the neonatal period is a critical window for brain development. The neurodevelopmental outcomes in neonates with ICH are determined by the maturity of the brain, the location and extent of the hemorrhage, the specific underlying etiology and the presence of other concomitant disorders. Neonatal ICH may result from various inherited and acquired disorders. We classify the etiologies of neonatal ICH into eight main categories: (1) Hemorrhagic stroke including large focal hematoma, (2) Prematurity-related hemorrhage, (3) Bleeding diathesis, (4) Genetic causes, (5) Infection, (6) Trauma-related hemorrhage, (7) Tumor-related hemorrhage and (8) Vascular malformations. Illustrative cases showing various imaging patterns that can be helpful to predict clinical outcomes will be highlighted. Potential mimics of ICH in the neonatal period are also reviewed.

Structure of the Medullary Veins of the Cerebral Hemisphere and Related Disorders

Deep medullary veins drain into subependymal veins with four convergence zones and show parallel distribution patterns adjacent to the body or inferior horn and a radial pattern in the frontal horn or trigon of the lateral ventricle. As white matter imaging develops such as diffusion tensor imaging or susceptibility-weighted imaging, requirements for understanding of white matter structures are increasing, not only for understanding of neuronal tracts but also for that of other structures including the fine anatomy of white matter vessels. Some disorders are related to deep medullary veins and show characteristic distributions of the lesions indicating the relationship to the medullary veins. When lesions show a parallel or radial distribution pattern in the certebral deep white matter, disorders related to deep medullary veins should be considered for differential diagnosis. In this review, we discuss disorders related to deep medullary veins, including (a) anomalies of the medullary veins, (b) hemorrhagic disorders related to the medullary veins (diffuse vascular injury due to high-energy trauma, deep medullary vein engorgement/thrombosis in neonates), (c) inflammatory changes that spread along the medullary veins, (d) neoplasms within the medullary veins, and (e) metabolic changes that lead to altered visualization of medullary veins. Understanding the anatomic structure of medullary veins in the cerebral hemisphere and becoming familiar with disorders in which the medullary veins play a major role in disease development may be helpful in the interpretation of brain images. ^©RSNA, 2017.

Pathways for Neuroimaging of Neonatal Stroke

PURPOSE

To provide consensus-based, suggested imaging protocols to facilitate the accurate and timely diagnosis of a neonate with symptoms concerning for stroke.

METHODS

The Writing Group, an international collaboration of pediatric neurologists and neuroradiologists with expertise in perinatal and childhood stroke, participated in a series of pediatric stroke neuroimaging symposia. These discussions, in conjunction with extensive literature review, led to a consensus for imaging protocols to guide practitioners in the diagnosis of neonatal stroke subtypes as defined by the National Institute of Neurological Disorders and Stroke Common Data Elements. The epidemiology, clinical presentation, and associated risk factors for arterial ischemic stroke, cerebral sinovenous thrombosis, and hemorrhagic stroke are reviewed, with a focused discussion regarding the role of neuroimaging for each subtype.

RESULTS

In a neonate with suspected stroke, magnetic resonance imaging is the preferred modality, given the lack of X-irradiation, superior anatomic resolution, and sensitivity for acute ischemia. Core recommended sequences include diffusion-weighted imaging and apparent diffusion coefficient mapping to diagnose acute ischemia, gradient-recalled echo or susceptibility-weighted imaging to detect intracranial blood and its breakdown products, and T1- and T2-weighted imaging to assess for myelination, extra-axial blood, and edema. Magnetic resonance angiography of the brain may be useful to detect vascular abnormalities, with venography if venous sinus thrombosis is suspected. The application of more novel sequences, as well as the utility of follow up-imaging, is also discussed.

Cerebral Sinovenous Thrombosis in the Asphyxiated Cooled Infants: A Prospective Observational Study

BACKGROUND

Cerebral sinovenous thrombosis is unusual in the asphyxiated cooled infants, but reliable data regarding the incidence of this comorbidity are lacking. We assessed the incidence of sinovenous thrombosis in a population of asphyxiated cooled infants by performing routine brain magnetic resonance venography.

METHODS

All asphyxiated infants who underwent therapeutic cooling at our institution completed brain magnetic resonance venography after rewarming. Assessing the incidence of cerebral sinovenous thrombosis was the primary goal. Secondary analyses included group comparisons for laboratory tests and monitored parameters, relationship between variables, logistic regression models, and receiver operating characteristic curve for cerebral sinovenous thrombosis prediction.

RESULTS

Cerebral sinovenous thrombosis was detected in 10 of 37 infants (27%), most commonly affecting the superior sagittal sinus (eight of ten). These infants manifested higher blanket (P < 0.001) and lower esophageal temperatures (P = 0.006), lower platelet counts (P = 0.045), and received more red blood cell transfusions (P = 0.038) than the cooled infants without thrombosis. Blanket temperature was independently associated with cerebral sinovenous thrombosis (P = 0.049), and 32°C/hour was the optimal cutoff value to predict the event (sensitivity, 90%; specificity, 88.5%).

CONCLUSIONS

High incidence or cerebral sinovenous thrombosis in neonates treated with therapeutic hypothermia suggests that magnetic resonance venography may be reasonable in many of these children. High blanket temperature may be one variable that helps identify patients at higher risk.

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.

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.

Cerebral sinovenous thrombosis in neonatal antiphospholipid syndrome: a new entity?

Neonatal antiphospholipid syndrome (neonatal APS) seems to be exceedingly rare, as the antiphospholipid antibodies (aPL) related thrombosis in the neonatal period. The pathogenesis of perinatal aPL related thrombosis may be explained both by the transplacental passage of the maternal antibodies and by the production of de novo antibodies by the neonate. However, few cases of neonatal APS are reported in the literature, especially regarding arterial thrombotic events. In particular, only two cases of neonatal aPL related isolated cerebral sinovenous thrombosis (CSVT) are described in the literature. Despite its frequency, CSVT results in significant mortality and morbidity, probably also due to the difficulty in early diagnosis and then in correct managing in the neonatal period. A diagnosis of neonatal APS should be considered in the evaluation of neonates with CSVT, as well as in any case of neonatal thrombosis, to correctly manage the affected neonates and counsel the mother for future pregnancies.

Cerebral Sinovenous Thrombosis in Children and Neonates

Our aim is to present the etiology and risk factors for cerebral sinovenous thrombosis (CSVT) and the radiological findings, anticoagulant therapy used, and treatment outcome of patients with CSVT. This study included 12 patients who were treated for CSVT at the Ankara University, School of Medicine, Department of Pediatric Neurology. This study included 5 girls (41.7%) and 7 boys (58.3%) with a mean age of symptom onset of 5.2 ± 6.29 years (range: 0-18 years), who were followed at our institution for a mean of 1.8 ± 1.73 years (range: 0-6.5 years). Among the patients, 3 had no risk factors, 2 had 1 risk factor, and 7 had multiple risk factors. Anticoagulant therapy was administered to 4 patients, of which 1 had neurological sequelae; neurological sequelae or exitus occurred in 4 of the 8 patients who did not receive anticoagulant therapy. The present findings showed that appropriate prophylaxis in appropriately selected patients reduced the rate of recurrence of CSVT.

Haemorrhagic stroke in term and late preterm neonates

OBJECTIVE

Few data regarding causes and outcomes of haemorrhagic stroke (HS) in term neonates are available. We characterised risk factors, mechanism and short-term outcomes in term and late preterm neonates with acute HS.

DESIGN

Prospective cohort.

SETTING

Single-centre tertiary care stroke registry.

SUBJECTS

Term and late preterm neonates (≥ 34 weeks gestation), born 2004-2010, with acute HS ≤ 28 days of life were identified, and clinical information was abstracted. Short-term outcomes were assessed via standardised neurological exam and rated using the Paediatric Stroke Outcome Measure (PSOM).

RESULTS

Among 42 neonates, median gestational age was 39.7 weeks (IQR 38-40.7 weeks). Diagnosis occurred at a median of 1 day (IQR 0-7 days) after delivery. Twenty-seven (64%) had intraparenchymal and intraventricular haemorrhage. Mechanism was haemorrhagic transformation of venous or arterial infarction in 22 (53%). Major risk factors included congenital heart disease (CHD), fetal distress and haemostatic abnormalities. Common presentations included seizure, apnoea, and poor feeding or vomiting. Acute hydrocephalus was common. Mortality was 12%. Follow-up occurred in 36/37 survivors at a median of 1 year (IQR 0.5-2.0 years). Among 17/36 survivors evaluated in stroke clinic, 47% demonstrated neurologic deficits. Deficits were mild (PSOM 0.5-1.5) in 9/36 (25%), and moderate-to-severe (PSOM ≥ 2.0) in 8/36 (22%).

CONCLUSIONS

In our cohort with acute HS, most presented with seizures, apnoea and/or poor feeding. Fetal distress and CHD were common. Nearly two-thirds had intraparenchymal with intraventricular haemorrhage. Over half were due to haemorrhagic transformation of infarction. Short-term neurologic deficits were present in 47% of survivors.

Different gestational ages and changing vulnerability of the premature brain

In recent decades, there has been a general increase in survival rates of preterm and low birth weight infants, but this overall decrease in perinatal mortality has not been accompanied by a decrease in long-term physical and mental disability. In order to reduce the long-term sequelae of prematurity and to establish preventive measures, it is important to identify risk factors since the main determinant of specific vulnerability to different types of lesions is gestational age. The regional tissue vulnerability at a given gestational age is probably determined by the local metabolic requirements together with specific cell characteristics and their level of maturation. In this article, we discuss the most common neonatal cerebral lesions (cerebellar haemorrhage, germinal matrix intraventricular haemorrhage, periventricular leukomalacia, arterial ischaemic stroke, cerebral vein sinus thrombosis and hypoxic-ischaemic encephalopathy) related to the gestational age-dependent vulnerability of the premature brain.

Alleviation of neonatal sinovenous compression to enhance cerebral venous blood flow

Occipital bone compression of the superior sagittal sinus occurs in supine neonates. The authors previously showed that this compression is associated with neonatal cerebral sinovenous thrombosis, an important neonatal neurological condition, presumably via increased venous stasis. They hypothesized that a pillow alleviating occipital compression could improve cerebral venous flow. Neonates without cerebral sinovenous thrombosis requiring brain magnetic resonance imaging/venography were prospectively enrolled. Demographics, imaging indications, head position, and superior sagittal sinus compression were recorded. Flow velocities in the anterior and posterior superior sagittal sinus and sigmoid sinus before and after pillow placement were quantified using Doppler ultrasound. A total of 10 neonates (6 female, median postconceptional age 40.6 weeks) were enrolled. Flow velocities increased beyond the superior sagittal sinus compression point following pillow placement: 0.09 ± 0.04 m/sec to 0.15 ± 0.12 m/sec (P = .047) for posterior superior sagittal sinus; 0.10 ± 0.05 m/sec to 0.19 ± 0.15 m/sec (P = .005) for sigmoid sinus. Pillow decompression can improve neonatal cerebral venous flow, representing a potential noninvasive intervention for the prevention and treatment of neonatal cerebral sinovenous thrombosis.

Fast-brain MRI in children is quick, without sedation, and radiation-free, but beware of limitations

Fast-brain MRI is a promising technique for young children who require anesthesia for conventional MRI; however, poor contrast resolution and the use of one type of pulse sequence only has limitations. We aimed to review and document pitfalls of fast-brain MRI in non-sedated children. Fifty fast-brain MRI studies (Fast Imaging Employing sTeady State Acquistion [FIESTA] protocol; 1.5-Tesla Signa Excite HD, GE HealthCare, Milwaukee, WI, USA) performed between January 2008 and August 2010 in 30 non-sedated patients aged 1 day to 5 years of age (mean: 18 months) were reviewed retrospectively and compared to the most recent MRI or CT scan. The indications were: ventriculoperitoneal (VP) shunt insertion or revision or follow-up (20/50, 40%), postoperative follow-up (9/50, 18%), macrocephaly, ventriculomegaly or congenital malformation (15/50, 30%), complications of prematurity (6/50, 12%). The VP shunt position and size of fluid-filled structures were satisfactorily assessed in all patients. Undetected findings in 7/50 studies (14%) were: venous sinus thrombosis (one patient), subdural hematoma (three), failure to differentiate blood products (two), and limited evaluation of extra-axial collections (one). FIESTA fast-brain MRI provides satisfactory assessment of shunt position and the size of fluid-filled structures, but radiologists should be aware of limitations for depiction of venous sinus thrombosis, and bleeding. Modification of fast-brain protocols appears to be indicated.

Color Doppler US of normal cerebral venous sinuses in neonates: a comparison with MR venography

BACKGROUND

Color Doppler US (CDUS) has been used for evaluation of cerebral venous sinuses in neonates. However, there is very limited information available regarding the appearance of superficial and deep normal cerebral venous sinuses using CDUS and the specificity of the technique to rule out disease.

OBJECTIVE

To determine the specificity, inter-modality and inter-reader agreement of color Doppler US (CDUS). To evaluate normal cerebral venous sinuses in neonates in comparison to MR venography (MRV).

MATERIALS AND METHODS

Newborns undergoing a clinically indicated brain MRI were prospectively evaluated. All underwent a dedicated CDUS of the cerebral venous sinuses within 10 h (mean, 3.5 h, range, and 2-7.6 h) of the MRI study using a standard protocol.

RESULTS

Fifty consecutive neonates participated in the study (30 males [60%]; 25-41 weeks old; mean, 37 weeks). The mean time interval between the date of birth and the CDUS study was 19.1 days. No cases showed evidence of thrombosis. Overall agreement for US reading was 97% (range, 82-100%), for MRV reading, 99% (range, 96-100%) and for intermodality, 100% (range, 96-100%). Excellent US-MRI agreement was noted for superior sagittal sinus, cerebral veins, straight sinus, torcular Herophili, sigmoid sinus, superior jugular veins (94-98%) and transverse sinuses (82-86%). In 10 cases (20%), MRV showed flow gaps whereas normal flow was demonstrated with US. Visualization of the inferior sagittal sinus was limited with both imaging techniques.

CONCLUSION

Excellent reading agreement was noted for US, MRV and intermodality. CDUS is highly specific to rule out cerebral venous thrombosis in neonates and holds potential for clinical application as part of clinical-laboratory-imaging algorithms of pre/post-test probabilities of disease.

Neonatal ischemic brain injury: what every radiologist needs to know

We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested.

Antithrombotic therapy in neonates and children: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

Neonates and children differ from adults in physiology, pharmacologic responses to drugs, epidemiology, and long-term consequences of thrombosis. This guideline addresses optimal strategies for the management of thrombosis in neonates and children.

METHODS

The methods of this guideline follow those described in the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.

RESULTS

We suggest that where possible, pediatric hematologists with experience in thromboembolism manage pediatric patients with thromboembolism (Grade 2C). When this is not possible, we suggest a combination of a neonatologist/pediatrician and adult hematologist supported by consultation with an experienced pediatric hematologist (Grade 2C). We suggest that therapeutic unfractionated heparin in children is titrated to achieve a target anti-Xa range of 0.35 to 0.7 units/mL or an activated partial thromboplastin time range that correlates to this anti-Xa range or to a protamine titration range of 0.2 to 0.4 units/mL (Grade 2C). For neonates and children receiving either daily or bid therapeutic low-molecular-weight heparin, we suggest that the drug be monitored to a target range of 0.5 to 1.0 units/mL in a sample taken 4 to 6 h after subcutaneous injection or, alternatively, 0.5 to 0.8 units/mL in a sample taken 2 to 6 h after subcutaneous injection (Grade 2C).

CONCLUSIONS

The evidence supporting most recommendations for antithrombotic therapy in neonates and children remains weak. Studies addressing appropriate drug target ranges and monitoring requirements are urgently required in addition to site- and clinical situation-specific thrombosis management strategies.

The "Shaken Baby" syndrome: pathology and mechanisms

The "Shaken Baby" syndrome (SBS) is the subject of intense controversy; the diagnosis has in the past depended on the triad of subdural haemorrhage (SDH), retinal haemorrhage and encephalopathy. While there is no doubt that infants do suffer abusive injury at the hands of their carers and that impact can cause catastrophic intracranial damage, research has repeatedly undermined the hypothesis that shaking per se can cause this triad. The term non-accidental head injury has therefore been widely adopted. This review will focus on the pathology and mechanisms of the three physiologically associated findings which constitute the "triad" and are seen in infants suffering from a wide range of non-traumatic as well as traumatic conditions. "Sub" dural bleeding in fact originates within the deep layers of the dura. The potential sources of SDH include: the bridging veins, small vessels within the dura itself, a granulating haemorrhagic membrane and ruptured intracranial aneurysm. Most neuropathologists do not routinely examine eyes, but the significance of this second arm of the triad in the diagnosis of Shaken Baby syndrome is such that it merits consideration in the context of this review. While retinal haemorrhage can be seen clinically, dural and subarachnoid optic nerve sheath haemorrhage is usually seen exclusively by the pathologist and only rarely described by the neuroradiologist. The term encephalopathy is used loosely in the context of SBS. It may encompass anything from vomiting, irritability, feeding difficulties or floppiness to seizures, apnoea and fulminant brain swelling. The spectrum of brain pathology associated with retinal and subdural bleeding from a variety of causes is described. The most important cerebral pathology is swelling and hypoxic-ischaemic injury. Mechanical shearing injury is rare and contusions, the hallmark of adult traumatic brain damage, are vanishingly rare in infants under 1 year of age. Clefts and haemorrhages in the immediate subcortical white matter have been assumed to be due to trauma but factors specific to this age group offer other explanations. Finally, examples of the most common causes of the triad encountered in clinical diagnostic and forensic practice are briefly annotated.

Deep medullary vein involvement in neonates with brain damage: an MR imaging study

BACKGROUND AND PURPOSE

Different and specific MR imaging patterns of lesions involving WM are widely defined in neonatal encephalopathy. The aim of this study was to describe a novel MR imaging pattern of damage characterized by the abnormal prominence of DMVs in premature and full-term neonates.

MATERIALS AND METHODS

Twenty-one (11 premature and 10 full-term) neonates with MR imaging evidence of linear radially oriented fan-shaped lesions in the periventricular WM and without dural venous thrombosis were enrolled in this retrospective study. A total of 37 MR imaging examinations were performed at ages ranging from day 0 to 24 months.

RESULTS

According to the appearance of linear anomalies on T2-weighted images, we identified 2 main patterns: T2 hypointense lesions without WM cavitations and T2 hypointense lesions associated with linear cysts. The first pattern was found in 17 examinations performed between 0 and 44 days of life; the second pattern was found in another 14 examinations performed between 6 days and 4 months of life. Five examinations performed between 9 and 24 months of life showed a reduction in volume and hyperintense signal intensity of the periventricular WM on T2-weighted and FLAIR images.

CONCLUSIONS

Subtle linear WM lesions with the same anatomic distribution of DMVs may be evident in premature and full-term neonates without signs of major venous thrombosis, both in the acute and subacute phases. Their appearance and evolution suggest that transient DMV engorgement/thrombosis may be responsible for WM damage that can lead to a PVL-like pattern.

A prospective outcome study of neonatal cerebral sinovenous thrombosis

Neonatal cerebral sinovenous thrombosis is a frequent contributor to neonatal mortality and morbidity. Treatment is controversial, and reported clinical outcomes vary widely. Newborns with radiologically confirmed neonatal cerebral sinovenous thrombosis from 1992 to 2009 were prospectively followed in our Children's Stroke Clinic for standardized outcomes, including the Pediatric Stroke Outcome Measure. Outcomes were available in 90 of 104 (87%) neonates. Early outcomes included cerebral sinovenous thrombosis-associated death (5) and thrombus propagation (15 [6 associated with new venous infarcts]). Lack of anticoagulation predicted propagation (RR = 13; P = .0007). Complete thrombus recanalization occurred in 90% by 3 months. Late outcomes (median, 2.5 years) were epilepsy (15) and neurological disability (50), which included moderate-severe language (43), sensorimotor (38), and cognitive/behavioral (24) deficits. Overall, 61% had poor outcome (death/any deficit). Concurrent neurological comorbidity at diagnosis (odds ratio = 2.8; P = .029) predicted poor outcome. Clinical trials are urgently needed to establish more effective treatment strategies.

Pediatric stroke

INTRODUCTION

Pediatric stroke, while increasingly recognized among practitioners as a clinically significant, albeit infrequent entity, remains challenging from the viewpoint of clinicians and researchers.

DISCUSSION

Advances in neuroimaging have revealed a higher prevalence of pediatric stroke while also provided a safer method for evaluating the child's nervous system and vasculature. An understanding of pathogenic mechanisms for pediatric stroke requires a division of ages (perinatal and childhood) and a separation of mechanism (ischemic and hemorrhagic). This article presents a review of the current literature with the recommended divisions of age and mechanism.

CONCLUSION

Guidelines for treatment, though limited, are also discussed.

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.

Sagittal sinus compression is associated with neonatal cerebral sinovenous thrombosis

OBJECTIVE

Neonatal cerebral sinovenous thrombosis (CSVT) causes lifelong morbidity. Newborns frequently incur positional occipital bone compression of the superior sagittal sinus (SSS). We hypothesized that SSS compression is associated with neonatal CSVT.

METHODS

Our retrospective case-control study recruited neonates with CSVT (SickKids Children's Stroke Program, January 1992-December 2006). Controls were neonates without CSVT undergoing magnetic resonance or computed tomography venography (institutional imaging database, 2002-2005) who were matched 2 per each case patient. Blinded neuroimaging review by 2 experts quantified SSS compression and head position. Effect of SSS compression on the primary outcome of CSVT was determined (logistic regression). Secondary analyses included the relationship of head position to SSS compression (t test) and group comparisons (cases versus controls, cases with and without compression) for demographic, clinical, and CSVT factors (χ² and Wilcoxon Mann-Whitney tests).

RESULTS

Case (n = 55) and control (n = 90) patients had similar ages and delivery modes. SSS compression was common (cases: 43%; controls: 41%). Controlling for gender and head position, SSS compression was associated with CSVT (odds ratio: 2.5 [95% confidence interval: 1.07-5.67]). Compression was associated with greater mean (SD) angle toward head flexion (101.2 [15.0] vs 111.5 [9.7]; P < .001). Among CSVT cases, neonates with and without compression had comparable gestational age, delivery mode, risk factors, anticoagulation treatment, thrombus location, propagation, infarction, recanalization, and outcome. Many idiopathic cases had SSS compression (79%). Interrater reliability of compression measurements was high (κ = 0.87).

CONCLUSIONS

Neonatal SSS compression is common, quantifiable, and associated with CSVT. Optimizing head position and/or developing devices to alleviate mechanical SSS compression may represent a novel means to improve outcomes.

Infant subcortical cystic leucomalacia: a distinct pathological entity resulting from impaired fluid handling

BACKGROUND

In the first months of life the subcortical white matter appears prone to fluid accumulation and cystic change. This condition has generally been considered to be due to hypoxic-ischaemic injury (HII) and is grouped with other forms of white matter disease including periventricular leucomalacia (PVL).

AIMS

Our aim was to describe the sequential tissue changes in the formation of subcortical cystic leucomalacia in the infant brain and to delineate this from other forms of white matter disease in order to better understand its pathogenesis and aetiology.

STUDY DESIGN

Standard samples of the frontal lobe, including subcortical white matter, were stained to demonstrate the cellular processes responsible for subcortical cyst formation in infants who had died from global hypoxic-ischaemic injury (HII) and brain swelling. Cases were of infants who had survived for known periods after collapse in order to determine the time course of the pathological changes.

SUBJECTS

20 infants under 5 months of age with global HII and no other primary brain pathology, and who had survived for between 2h and 13 days after collapse.

OUTCOME MEASURES

The description of the sequential changes leading to subcortical cyst formation in infants after severe global HII.

RESULTS

With increasing time of survival after global HII the subcortical white matter became more oedematous. Subcortical cysts were seen after one day but were most common in infants surviving more than 5 days. Cysts were not associated with cellular responses and seemed to be the result of fluid accumulation. The pathology was quite distinct from PVL which is due to tissue necrosis.

CONCLUSIONS

Subcortical leucomalacia results from fluid accumulation and not necrosis. Predisposition to fluid accumulation may be age-related and due to impairment of fluid handling pathways which remain immature in this age group. Potential mechanisms are discussed.

Intracranial hemorrhage in full-term newborns: a hospital-based cohort study

INTRODUCTION

In recent years, intracranial hemorrhage (ICH) with parenchymal involvement has been diagnosed more often in full-term neonates due to improved neuroimaging techniques. The aim of this study is to describe clinical and neuroimaging data in the neonatal period and relate imaging findings to outcome in a hospital-based population admitted to a level 3 neonatal intensive care unit (NICU).

METHODS

From our neuroimaging database, we retrospectively retrieved records and images of 53 term infants (1991-2008) in whom an imaging diagnosis of ICH with parenchymal involvement was made. Clinical data, including mode of delivery, clinical manifestations, neurological symptoms, extent and site of hemorrhage, neurosurgical intervention, and neurodevelopmental outcomes, were recorded.

RESULTS

Seventeen of the 53 term infants had infratentorial ICH, 20 had supratentorial ICH, and 16 had a combination of the two. Seizures were the most common presenting symptom (71.7%), another ten infants (18.9%) presented with apneic seizures, and five infants had no clinical signs but were admitted to our NICU because of perinatal asphyxia (n=2), respiratory distress (n=2), and development of posthemorrhagic ventricular dilatation (n=1). Continuous amplitude-integrated electroencephalography recordings were performed in all infants. Clinical or subclinical seizures were seen in 48/53 (90.6%) infants; all received anti-epileptic drugs. Thirteen of all 53 (24.5%) infants died. The lowest mortality rate was seen in infants with supratentorial ICH (10%). Three infants with a midline shift required craniotomy, six infants needed a subcutaneous reservoir due to outflow obstruction, and three subsequently required a ventriculoperitoneal shunt. The group with poor outcome (death or developmental quotient (DQ) <85) had a significantly lower 5-min Apgar score (p=.006). Follow-up data were available for 37/40 survivors aged at least 15 months. Patients were assessed with the Griffiths Mental Developmental Scales, and the mean DQ of all survivors was 97 (SD=12). Six infants (17%) had a DQ below 85 [two of them had cerebral palsy (CP)]. Three infants developed CP (8.6%); one had cerebellar ataxia, and two had hemiplegia.

CONCLUSION

ICH with parenchymal involvement carries a risk of adverse neurological sequelae with a mortality of 24.5% and development of CP in 8.6%. The high mortality rate could partly be explained by associated perinatal asphyxia. Infants with supratentorial ICH had a lower, although not significant, mortality rate compared with infants with infratentorial ICH and infants with a combination of supratentorial ICH and infratentorial ICH. In spite of often large intraparenchymal lesions, 30 of the 34 survivors without CP (88.2%) had normal neurodevelopmental outcome at 15 months.

Neonatal cerebral sinovenous thrombosis: sifting the evidence for a diagnostic plan and treatment strategy

Although cerebral sinovenous thrombosis (CSVT) is an uncommon disorder in neonates, the incumbent morbidity, mortality, and adverse neurodevelopmental sequelae highlight the importance of establishing an early diagnosis with an appropriate therapeutic plan. The clinical signs and symptoms of the condition are subtle and invariably masquerade under the umbrella of a broad spectrum of neonatal illnesses. A high index of diagnostic suspicion is essential for investigating and initiating treatment in a timely fashion before major complications ensue. Recent advances in accessible radiographic techniques with reduced radiation exposure have facilitated rapid diagnosis of thrombosis in both the superficial and deep plexuses of the cerebral venous systems. The absence of large-scale randomized trials and solid prospective smaller-sample-sized studies of neonates with CSVT has compromised our ability to develop efficacious treatment decisions. In this review of the scientific literature we offer understanding of the complex etiology of CSVT and inherent problems involved in the diagnosis and treatment of the disorder and focus on the limitations in current follow-up. An approach to neonatal CSVT is proposed on the basis of the available evidence from guidelines, registries, prospective and retrospective infant studies, and case series.

MRI of perinatal brain injury

MRI is invaluable in assessing the neonatal brain following suspected perinatal injury. Good quality imaging requires adaptations to both the hardware and the sequences used for adults or older children. The perinatal and postnatal details often predict the pattern of lesions sustained and should be available to aid interpretation of the imaging findings. Perinatal lesions, the pattern of which can predict neurodevelopmental outcome, are at their most obvious on conventional imaging between 1 and 2 weeks from birth. Very early imaging during the first week may be useful to make management decisions in ventilated neonates but brain abnormalities may still be subtle using conventional sequences. Diffusion-weighted imaging (DWI) is very useful for the early identification of ischaemic tissue in the neonatal brain but may underestimate the final extent of injury, particularly basal ganglia and thalamic lesions. MR imaging is an excellent predictor of outcome following perinatal brain injury and can therefore be used as a biomarker in interventional trials designed to reduce injury and improve neurodevelopmental outcome.