Paediatric hydrocephalus.

Hydrocephalus is classically considered as a failure of cerebrospinal fluid (CSF) homeostasis that results in the active expansion of the cerebral ventricles. Infants with hydrocephalus can present with progressive increases in head circumference whereas older children often present with signs and symptoms of elevated intracranial pressure. Congenital hydrocephalus is present at or near birth and some cases have been linked to gene mutations that disrupt brain morphogenesis and alter the biomechanics of the CSF-brain interface. Acquired hydrocephalus can develop at any time after birth, is often caused by central nervous system infection or haemorrhage and has been associated with blockage of CSF pathways and inflammation-dependent dysregulation of CSF secretion and clearance. Treatments for hydrocephalus mainly include surgical CSF shunting or endoscopic third ventriculostomy with or without choroid plexus cauterization. In utero treatment of fetal hydrocephalus is possible via surgical closure of associated neural tube defects. Long-term outcomes for children with hydrocephalus vary widely and depend on intrinsic (genetic) and extrinsic factors. Advances in genomics, brain imaging and other technologies are beginning to refine the definition of hydrocephalus, increase precision of prognostication and identify nonsurgical treatment strategies.

Nerve-Targeted Surgical Treatments for Spasticity: A Narrative Review.

Spasticity is a potentially debilitating symptom of various acquired and congenital neurologic pathologies that, without adequate treatment, may lead to long-term disability, compromise functional independence, and negatively impact mental health. Several conservative as well as non-nerve targeted surgical strategies have been developed for the treatment of spasticity, but these may be associated with significant drawbacks, such as adverse side effects to medication, device dependence on intrathecal baclofen pumps, and inadequate relief with tendon-based procedures. In these circumstances, patients may benefit from nerve-targeted surgical interventions such as (i) selective dorsal rhizotomy, (ii) hyperselective neurectomy, and (iii) nerve transfer. When selecting the appropriate surgical approach, preoperative patient characteristics, as well as the risks and benefits of nerve-targeted surgical intervention, must be carefully evaluated. Here, we review the current evidence on the efficacy of these nerve-targeted surgical approaches for treating spasticity across various congenital and acquired neurologic pathologies.

Soluble PD-L1 reprograms blood monocytes to prevent cerebral edema and facilitate recovery after ischemic stroke.

Acute cerebral ischemia triggers a profound inflammatory response. While macrophages polarized to an M2-like phenotype clear debris and facilitate tissue repair, aberrant or prolonged macrophage activation is counterproductive to recovery. The inhibitory immune checkpoint Programmed Cell Death Protein 1 (PD-1) is upregulated on macrophage precursors (monocytes) in the blood after acute cerebrovascular injury. To investigate the therapeutic potential of PD-1 activation, we immunophenotyped circulating monocytes from patients and found that PD-1 expression was upregulated in the acute period after stroke. Murine studies using a temporary middle cerebral artery (MCA) occlusion (MCAO) model showed that intraperitoneal administration of soluble Programmed Death Ligand-1 (sPD-L1) significantly decreased brain edema and improved overall survival. Mice receiving sPD-L1 also had higher performance scores short-term, and more closely resembled sham animals on assessments of long-term functional recovery. These clinical and radiographic benefits were abrogated in global and myeloid-specific PD-1 knockout animals, confirming PD-1+ monocytes as the therapeutic target of sPD-L1. Single-cell RNA sequencing revealed that treatment skewed monocyte maturation to a non-classical Ly6Clo, CD43hi, PD-L1+ phenotype. These data support peripheral activation of PD-1 on inflammatory monocytes as a therapeutic strategy to treat neuroinflammation after acute ischemic stroke.

Risk of Subdural Hematoma Expansion in Patients With End-Stage Renal Disease: Continuous Venovenous Hemodialysis Versus Intermittent Hemodialysis.

BACKGROUND AND OBJECTIVES: Subdural hematoma (SDH) patients with end-stage renal disease (ESRD) require renal replacement therapy in addition to neurological management. We sought to determine whether continuous venovenous hemodialysis (CVVHD) or intermittent hemodialysis (iHD) is associated with higher rates of SDH re-expansion as well as morbidity and mortality. METHODS: Hemodialysis-dependent patients with ESRD who were discovered to have an SDH were retrospectively identified from 2016 to 2022. Rates of SDH expansion during CVVHD vs iHD were compared. Hemodialysis mode was included in a multivariate logistic regression model to test for independent association with SDH expansion and mortality. RESULTS: A total of 123 hemodialysis-dependent patients with ESRD were discovered to have a concomitant SDH during the period of study. Patients who received CVVHD were on average 10.2 years younger ( P < .001), more likely to have traumatic SDH (47.7% vs 19.0%, P < .001), and more likely to have cirrhosis (25.0% vs 10.1%, P = .029). SDH expansion affecting neurological function occurred more frequently during iHD compared with CVVHD (29.7% vs 12.0%, P = .013). Multivariate logistic regression analysis found that CVVHD was independently associated with decreased risk of SDH affecting neurological function (odds ratio 0.25, 95% CI 0.08-0.65). Among patients who experienced in-hospital mortality or were discharged to hospice, 5% suffered a neurologically devastating SDH expansion while on CVVHD compared with 35% on iHD. CONCLUSION: CVVHD was independently associated with decreased risk of neurologically significant SDH expansion. Therefore, receiving renal replacement therapy through a course of CVVHD may increase SDH stability in patients with ESRD.

Socioeconomic characteristics and postoperative outcomes of patients undergoing prenatal vs. postnatal repair of myelomeningoceles.

PURPOSE: To investigate differences in sociodemographic characteristics and short-term outcomes between patients undergoing prenatal versus postnatal myelomeningocele repair. METHODS: Patients who underwent myelomeningocele repair at our institution were stratified based on prenatal or postnatal timing of repair. Baseline characteristics and outcomes were compared. Multivariate analysis was performed to identify whether prenatal repair was a predictor of outcomes independent of socioeconomic measures. RESULTS: 49 patients underwent postnatal repair, and 30 underwent prenatal repair. Patients who underwent prenatal repair were more likely to have private insurance (73.3% vs. 42.9%, p = 0.03) and live farther from the hospital where they received their repair (251.5 ± 447.4 vs. 72.5 ± 205.6 miles, p = 0.02). Patients who underwent prenatal repair had shorter hospital stays (14.3 ± 22.7 days vs. 25.3 ± 20.1 days, p = 0.03), fewer complications (13.8% vs. 42.9%, p = 0.01), fewer 30-day ED visits (0.0% vs. 34.0%, p < 0.001), lower CSF diversion rates (13.8% vs. 38.8%, p = 0.02), and better functional status at 3-months (13.3% vs. 57.1% delayed, p = 0.009), 6-months (20.0% vs. 56.7% delayed, p = 0.03), and 1-year (29.4% vs. 70.6% delayed, p = 0.007). On multivariate analysis, prenatal repair was an independent predictor of inpatient complication (OR(95%CI): 0.19(0.05-0.75), p = 0.02) and 3-month (OR(95%CI): 0.14(0.03-0.80) p = 0.03), 6-month (OR(95%CI): 0.12(0.02-0.73), p = 0.02), and 1-year (OR(95%CI): 0.19(0.05-0.80), p = 0.02) functional status. CONCLUSION: Prenatal repair for myelomeningocele is associated with better outcomes and developmental functional status. However, patients receiving prenatal closure are more likely to have private health insurance and live farther from the hospital, suggesting potential barriers to care.

Pilot Translational Precision Biobehavioral Assays for Early Detection of Motor Impairments in a Rat Model of Cerebral Palsy.

BACKGROUND: Cutting-edge neonatal programs diagnose cerebral palsy (CP) or "high risk of CP" using validated neurobehavioral exams in combination with risk history and neuroimaging. In rat models, digital gait analyses are the gold standard adult assessment, but tools in infant rats are limited. Refinement of infant rat neurobehavioral correlates of CP will establish translational behavioral biomarkers to delineate early mechanisms of CP in both humans and rodent models of CP. OBJECTIVE: To facilitate precision medicine approaches of neurodevelopmental health and integrate basic and clinical research approaches for CP, we developed and piloted a new assay of neonatal rat neurobehavior to mimic human neonate exams. METHODS: Our established rat model of CP secondary to chorioamnionitis (CHORIO) that induces bilateral motor impairment reminiscent of spastic CP was used. On postnatal day 10 (P10), 5 min videos were recorded of 26 (6 sham and 20 CHORIO) animals moving freely in a cage were reviewed by an evaluator trained in the human General Movements Assessment (GMA). Non-blinded observation revealed two behaviors that differed between rat pups in each group (time spent rearing; multi-dimensional nose sweeping; and sniffing). Each video was re-coded for these criteria by an evaluator blind to group status. Differences between sham and CP groups were analyzed using a Mann-Whitney U-test or Student's t-test (p < 0.05 level of significance). RESULTS: Neonatal rats with CP exhibited sensorimotor impairment and decreased spatial exploration. CP rats spent significantly less time rearing (17.85 ± 1.60 s vs. 34.8 ± 2.89 s, p = 0.007) and engaged in multi-dimensional nose sweeping and sniffing (2.2 ± 0.58 episodes vs. 5.5 ± 0.96 episodes, p = 0.03) than sham controls. CONCLUSIONS: These pilot findings of harmonized translational and precision biobehavioral assays provide an opportunity for increased expediency of clinical trials at the earliest stages of brain development.

Chorioamnionitis disrupts erythropoietin and melatonin homeostasis through the placental-fetal-brain axis during critical developmental periods.

Introduction: Novel therapeutics are emerging to mitigate damage from perinatal brain injury (PBI). Few newborns with PBI suffer from a singular etiology. Most experience cumulative insults from prenatal inflammation, genetic and epigenetic vulnerability, toxins (opioids, other drug exposures, environmental exposure), hypoxia-ischemia, and postnatal stressors such as sepsis and seizures. Accordingly, tailoring of emerging therapeutic regimens with endogenous repair or neuro-immunomodulatory agents for individuals requires a more precise understanding of ligand, receptor-, and non-receptor-mediated regulation of essential developmental hormones. Given the recent clinical focus on neurorepair for PBI, we hypothesized that there would be injury-induced changes in erythropoietin (EPO), erythropoietin receptor (EPOR), melatonin receptor (MLTR), NAD-dependent deacetylase sirtuin-1 (SIRT1) signaling, and hypoxia inducible factors (HIF1α, HIF2α). Specifically, we predicted that EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α alterations after chorioamnionitis (CHORIO) would reflect relative changes observed in human preterm infants. Similarly, we expected unique developmental regulation after injury that would reveal potential clues to mechanisms and timing of inflammatory and oxidative injury after CHORIO that could inform future therapeutic development to treat PBI. Methods: To induce CHORIO, a laparotomy was performed on embryonic day 18 (E18) in rats with transient uterine artery occlusion plus intra-amniotic injection of lipopolysaccharide (LPS). Placentae and fetal brains were collected at 24 h. Brains were also collected on postnatal day 2 (P2), P7, and P21. EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α levels were quantified using a clinical electrochemiluminescent biomarker platform, qPCR, and/or RNAscope. MLT levels were quantified with liquid chromatography mass spectrometry. Results: Examination of EPO, EPOR, and MLTR1 at 24 h showed that while placental levels of EPO and MLTR1 mRNA were decreased acutely after CHORIO, cerebral levels of EPO, EPOR and MLTR1 mRNA were increased compared to control. Notably, CHORIO brains at P2 were SIRT1 mRNA deficient with increased HIF1α and HIF2α despite normalized levels of EPO, EPOR and MLTR1, and in the presence of elevated serum EPO levels. Uniquely, brain levels of EPO, EPOR and MLTR1 shifted at P7 and P21, with prominent CHORIO-induced changes in mRNA expression. Reductions at P21 were concomitant with increased serum EPO levels in CHORIO rats compared to controls and variable MLT levels. Discussion: These data reveal that commensurate with robust inflammation through the maternal placental-fetal axis, CHORIO impacts EPO, MLT, SIRT1, and HIF signal transduction defined by dynamic changes in EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α mRNA, and EPO protein. Notably, ligand-receptor mismatch, tissue compartment differential regulation, and non-receptor-mediated signaling highlight the importance, complexity and nuance of neural and immune cell development and provide essential clues to mechanisms of injury in PBI. As the placenta, immune cells, and neural cells share many common, developmentally regulated signal transduction pathways, further studies are needed to clarify the perinatal dynamics of EPO and MLT signaling and to capitalize on therapies that target endogenous neurorepair mechanisms.

In utero methadone exposure permanently alters anatomical and functional connectivity: A preclinical evaluation.

The opioid epidemic is an ongoing public health crisis, and children born following prenatal opioid exposure (POE) have increased risk of long-term cognitive and behavioral sequelae. Clinical studies have identified reduced gray matter volume and abnormal white matter microstructure in children with POE but impacts on whole-brain functional brain connectivity (FC) have not been reported. To define effects of POE on whole brain FC and white matter injury in adult animals, we performed quantitative whole-brain structural and functional MRI. We used an established rat model of POE in which we have previously reported impaired executive function in adult rats analogous to persistent neurocognitive symptoms described in humans with POE. Pregnant Sprague-Dawley rat dams received continuous methadone (12 mg/kg/day) vs. saline infusion for 28 days via osmotic mini-pumps, exposing rats to pre- and postnatal opioid until weaning. At young adult age (P60), POE and saline exposed offspring underwent in vivo MRI included diffusion tensor imaging and functional MRI (fMRI). Results indicate that fractional anisotropy (FA) was decreased in adult animals with POE [n = 11] compared to animals that received saline [n = 9] in major white matter tracts, including the corpus callosum (p < 0.001) and external capsule (p < 0.01). This change in FA was concomitant with reduced axial diffusivity in the external capsule (p < 0.01) and increased radial diffusivity in the corpus callosum (p < 0.01). fMRI analyses reveal brainwide FC was diffusely lower in POE (p < 10-6; 10% of variance explained by group). Decreased connectivity in cortical-cortical and cortico-basal ganglia circuitry was particularly prominent with large effect sizes (Glass's Δ > 1). Taken together, these data confirm POE reduces brainwide functional connectivity as well as microstructural integrity of major white matter tracts. Altered neural circuitry, dysregulated network refinement, and diffuse network dysfunction have been implicated in executive function deficits that are common in children with POE. FC may serve as a translatable biomarker in children with POE.

Corrigendum: Methadone alters the peripheral inflammatory and central immune landscape following prenatal exposure in rats.

[This corrects the article DOI: 10.3389/adar.2022.10792.].

A second dimension of somatosensory system injury? Thalamic volume loss and neuropathic pain in adults with cerebral palsy and periventricular white matter injury.

Objectives: Lemniscal (motor-related) and spinothalamic (neuropathic pain-related) somatosensory abnormalities affect different subsets of adults with cerebral palsy (CP). Lemniscal/motor abnormalities are associated with posterior thalamic radiation white matter disruption in individuals with CP and white matter injury. We tested the hypothesis that neuropathic pain symptoms in this population are rather associated with injury of the somatosensory (posterior group nuclei) thalamus. Methods: In this cross-sectional study, communicative adults with CP and bilateral white matter injury and neurotypical control participants volunteered to self-report pain symptoms and undergo research MRI. Posterior group thalamic nuclei volume was computed and correlated against neuropathic pain scores. Results: Participants with CP (n=6) had, on average, 24% smaller posterior group thalamic volumes (95% CI [10-39%]; corrected p=0.01) than control participants. More severe volume loss was correlated with more severe neuropathic pain scores (ρ=-0.87 [-0.99,-0.20]; p=0.02). Discussion: Association with thalamic volume loss suggests that neuropathic pain in adults with CP may frequently be central neuropathic pain. Complementing assessments of white matter microstructure, regional brain volumes hold promise as diagnostic biomarkers for central neuropathic pain in individuals with structural brain disorders.

Prenatal and postnatal insults differentially contribute to executive function and cognition: Utilizing touchscreen technology for perinatal brain injury research.

The use of touchscreen technology to evaluate cognitive deficits in animal models has grown tremendously over the past 20 years. The touchscreen apparatus encompasses many advantages, namely a high level of standardization and translational capability. Improvements in technology in recent years have expanded the versatility of the touchscreen platform, as it is able to test distinct cognitive modalities including working memory, attention, discrimination, and association. Importantly, touchscreen technology has allowed researchers to explore deficits in multiple pillars of cognition in a wide variety of perinatal disorders with neurological sequelae across critical developmental windows. The touchscreen platform has been used to dissect deficits in antenatal CNS injury including fetal alcohol syndrome, prenatal opioid exposure, and chorioamnionitis, to peripartum insults such as term hypoxic-ischemic encephalopathy, to early postnatal insults including infantile traumatic brain injury. Most importantly, touchscreen technology offers the sensitivity necessary to detect subtle injury and treatment-induced changes in cognition and executive function beyond those offered by more rudimentary tests of rodent cognition. Understanding the pathophysiology of these disorders in rodents is paramount to addressing these deficits in human infants and dissecting the neural circuitry essential to perinatal brain injury pathophysiology and responsiveness to novel therapeutics. Touchscreen testing provides an effective, facile, sophisticated technique to accelerate the goal of improving cognitive and behavioral outcomes of children who suffer perinatal brain injury.

Pathogenesis of posthemorrhagic hydrocephalus of prematurity: New horizons.

Posthemorrhagic hydrocephalus of prematurity (PHHP) remains a vexing problem for patients, their families, and the healthcare system. The complexity of the pathogenesis of PHHP also presents a unique challenge within the fields of neonatology, neurology and neurosurgery. Here we focus on pathogenesis of PHHP and its impact on the development of CSF dynamics including choroid plexus, ependymal motile cilia and glymphatic system. PHHP is contrasted with infantile hydrocephalus from other etiologies, and with other types of posthemorrhagic hydrocephalus that occur later in life. The important concept that distinguishing ventricular volume from brain health and function is highlighted. The influence of the pathogenesis of PHHP on current interventions is reviewed, with particular emphasis on how the unique pathogenesis of PHHP contributes to the high rate of failure of current existing interventions. Finally, we discuss emerging interventions. A thorough understanding of the pathogenesis of PHHP is essential to developing effective non-surgical therapeutics to prevent the transformation from severe IVH to PHHP.

Infantile Cocktail of Erythropoietin and Melatonin Restores Gait in Adult Rats with Preterm Brain Injury.

Cerebral palsy (CP) is the most common cause of physical disability for children worldwide. Many infants and toddlers are not diagnosed with CP until they fail to achieve obvious motor milestones. Currently, there are no effective pharmacologic interventions available for infants and toddlers to substantially improve their trajectory of neurodevelopment. Because children with CP from preterm birth also exhibit a sustained immune system hyper-reactivity, we hypothesized that neuro-immunomodulation with a regimen of repurposed endogenous neurorestorative medications, erythropoietin (EPO) and melatonin (MLT), could improve this trajectory. Thus, we administered EPO + MLT to rats with CP during human infant-toddler equivalency to determine whether we could influence gait patterns in mature animals. After a prenatal injury on embryonic day 18 (E18) that mimics chorioamnionitis at ∼25 weeks human gestation, rat pups were born and raised with their dam. Beginning on postnatal day 15 (P15), equivalent to human infant ∼1 year, rats were randomized to receive either a regimen of EPO + MLT or vehicle (sterile saline) through P20. Gait was assessed in young adult rats at P30 using computerized digital gait analyses including videography on a treadmill. Results indicate that gait metrics of young adult rats treated with an infantile cocktail of EPO + MLT were restored compared to vehicle-treated rats (p < 0.05) and similar to sham controls. These results provide reassuring evidence that pharmacological interventions may be beneficial to infants and toddlers who are diagnosed with CP well after the traditional neonatal window of intervention.

Methadone alters the peripheral inflammatory and central immune landscape following prenatal exposure in rats.

Opioid use during pregnancy continues to rise at alarming rates with a parallel trend in the number of infants and children exposed to opioid medications each year. Prenatal opioid exposure (POE) occurs at a critical timepoint in neurodevelopment disrupting intricate pathways essential for neural-immune maturation with the potential for devastating long-term consequences. Understanding the mechanisms underlying injury associated with POE is essential to address long-term outcomes and identify diagnostic and therapeutic biomarkers in this vulnerable patient population. Using an established preclinical model of POE, we investigated changes in cerebral and peripheral inflammation and peripheral blood mononuclear cell (PBMC) activity. We hypothesized that neuroinflammation, as defined by changes in specific cerebral immune cell populations, would exist in adult rats following POE concomitant with sustained peripheral immune hyperreactivity (SPIHR). Our data demonstrated alterations in cerebral immune cells at postnatal day 60 (P60) typified by increased regulatory T cells (p < 0.01) and neutrophils (p < 0.05) in rats with POE compared to controls. Evaluation of serum revealed increased levels of IL-6 (p < 0.05) and CXCL1 (p < 0.05) at P21 in rats with POE compared to controls with no significant difference in cytokine or chemokine levels between the two groups at P60. Additionally, PBMCs isolated from rats with POE at P21 demonstrated baseline hypersecretion of IL-6 (p < 0.01) and SPIHR with increased levels of TNF-α (p < 0.05) and CXCL1 (p < 0.05) following stimulation with LPS. At P60, however, there was no significant difference found in cytokine or chemokine levels secreted by PBMCs isolated from rats with POE at baseline or with LPS stimulation when compared to controls. Taken together, these data demonstrate cerebral inflammation months after prenatal opioid exposure and long after the resolution of systemic inflammation and SPIHR seen at toddler age equivalent. Chronic alterations in the cerebral immune cell populations secondary to prenatal opioid exposure may underly long-term consequences of developmental brain injury including deficits in cognition and attention. These findings may be invaluable to further investigations of precise biomarkers of injury and targeted therapeutics for this vulnerable population.

Isolated and On Guard: Preparing Neonatal Intensive Care Unit Families for Life with Hydrocephalus.

OBJECTIVE: This study was aimed to characterize the parent experience of caring for a child with posthemorrhagic hydrocephalus and to describe parent preferences for counseling in the neonatal period and beyond. STUDY DESIGN: This was a qualitative interview study. Parents of infants born preterm with posthemorrhagic hydrocephalus completed semistructured interviews. Data were analyzed using a content analysis approach. RESULTS: Thematic saturation was reached on parent communication preferences after 10 interviews. Parent experiences of infant hydrocephalus broadly fell into two time periods, the neonatal intensive care unit (NICU) and after NICU discharge. The themes of uncertainty, isolation, hypervigilance, and the need for advocacy were common to each phase. CONCLUSION: Parents expressed interest in the development of tiered NICU counseling tools that would provide evidence-based and family-centric information to (1) initiate connections with community and peer resources and (2) combat the isolation and hypervigilance that characterized their family experience of living with hydrocephalus. KEY POINTS: · Infants with posthemorrhagic hydrocephalus are at risk for adverse neurodevelopmental outcomes.. · The parent experience of caring for a child with posthemorrhagic hydrocephalus is not well-described. In this interview study, parents described uncertainty, isolation, and hypervigilance.. · These findings call for structured NICU counseling and longitudinal family supports after discharge..

Neonatal administration of erythropoietin attenuates cognitive deficits in adult rats following placental insufficiency.

Preterm birth is a principal cause of neurological disability later in life, including cognitive and behavioral deficits. Notably, cognitive impairment has greater impact on quality of life than physical disability. Survivors of preterm birth commonly have deficits of executive function. Difficulties with tasks and planning complexity correlate positively with increasing disability. To overcome these barriers for children born preterm, preclinical and clinical studies have emphasized the importance of neurorestoration. Erythropoietin (EPO) is a endogenous cytokine with multiple beneficial mechanisms of action following perinatal brain injury. While most preclinical investigations have focused on pathology and molecular mechanisms, translational studies of repair using clinically viable biobehavioral biomarkers are still lacking. Here, using an established model of encephalopathy of prematurity secondary to placental insufficiency, we tested the hypothesis that administration of EPO in the neonatal period would attenuate deficits in recognition memory and cognitive flexibility in adult rats of both sexes. We assessed cognition and executive function in two ways. First, using the classic test of novel object recognition and second, using a touchscreen platform. Touchscreen testing allows for rigorous testing of cognition and executive function in preclinical and clinical scenarios. Data show that adult rats exhibit deficits in recognition memory and cognitive flexibility following in utero placental insufficiency. Notably, neonatal treatment of EPO attenuates these deficits in adulthood and facilitates functional repair. Together, these data validate EPO neurorestoration using a clinically relevant outcome measure and support the concept that postnatal treatment following in utero injury can improve cognition and executive function through adulthood.

Sustained peripheral immune hyper-reactivity (SPIHR): an enduring biomarker of altered inflammatory responses in adult rats after perinatal brain injury.

BACKGROUND: Chorioamnionitis (CHORIO) is a principal risk factor for preterm birth and is the most common pathological abnormality found in the placentae of preterm infants. CHORIO has a multitude of effects on the maternal-placental-fetal axis including profound inflammation. Cumulatively, these changes trigger injury in the developing immune and central nervous systems, thereby increasing susceptibility to chronic sequelae later in life. Despite this and reports of neural-immune changes in children with cerebral palsy, the extent and chronicity of the peripheral immune and neuroinflammatory changes secondary to CHORIO has not been fully characterized. METHODS: We examined the persistence and time course of peripheral immune hyper-reactivity in an established and translational model of perinatal brain injury (PBI) secondary to CHORIO. Pregnant Sprague-Dawley rats underwent laparotomy on embryonic day 18 (E18, preterm equivalent). Uterine arteries were occluded for 60 min, followed by intra-amniotic injection of lipopolysaccharide (LPS). Serum and peripheral blood mononuclear cells (PBMCs) were collected at young adult (postnatal day P60) and middle-aged equivalents (P120). Serum and PBMCs secretome chemokines and cytokines were assayed using multiplex electrochemiluminescent immunoassay. Multiparameter flow cytometry was performed to interrogate immune cell populations. RESULTS: Serum levels of interleukin-1ß (IL-1ß), IL-5, IL-6, C-X-C Motif Chemokine Ligand 1 (CXCL1), tumor necrosis factor-α (TNF-α), and C-C motif chemokine ligand 2/monocyte chemoattractant protein-1 (CCL2/MCP-1) were significantly higher in CHORIO animals compared to sham controls at P60. Notably, CHORIO PBMCs were primed. Specifically, they were hyper-reactive and secreted more inflammatory mediators both at baseline and when stimulated in vitro. While serum levels of cytokines normalized by P120, PBMCs remained primed, and hyper-reactive with a robust pro-inflammatory secretome concomitant with a persistent change in multiple T cell populations in CHORIO animals. CONCLUSIONS: The data indicate that an in utero inflammatory insult leads to neural-immune changes that persist through adulthood, thereby conferring vulnerability to brain and immune system injury throughout the lifespan. This unique molecular and cellular immune signature including sustained peripheral immune hyper-reactivity (SPIHR) and immune cell priming may be a viable biomarker of altered inflammatory responses following in utero insults and advances our understanding of the neuroinflammatory cascade that leads to perinatal brain injury and later neurodevelopmental disorders, including cerebral palsy.

Epidemiology and outcomes of pediatric intracranial aneurysms: comparison with an adult population in a 30-year, prospective database.

OBJECTIVE: Pediatric intracranial aneurysms are rare. Most large series in the last 15 years reported on an average of only 39 patients. The authors sought to report their institutional experience with pediatric intracranial aneurysms from 1991 to 2021 and to compare pediatric patient and aneurysm characteristics with those of a contemporaneous adult cohort. METHODS: Pediatric (≤ 18 years of age) and adult patients with one or more intracranial aneurysms were identified in a prospective database. Standard epidemiological features and outcomes of each pediatric patient were retrospectively recorded. These results were compared with those of adult aneurysm patients managed at a single institution over the same time period. RESULTS: From a total of 4500 patients with 5150 intracranial aneurysms admitted over 30 years, there were 47 children with 53 aneurysms and 4453 adults with 5097 aneurysms; 53.2% of children and 36.4% of adults presented with a subarachnoid hemorrhage (SAH). Pediatric aneurysms were significantly more common in males, more likely giant (≥ 25 mm), and most frequently located in the middle cerebral artery. Overall, 85.1% of the pediatric patients had a modified Rankin Scale score ≤ 2 at the last follow-up (with a mean follow-up of 65.9 months), and the pediatric mortality rate was 10.6%; all 5 patients who died had an SAH. The recurrence rate of treated aneurysms was 6.7% (1/15) in the endovascular group but 0% (0/31) in the microsurgical group. No de novo aneurysms occurred in children (mean follow-up 5.5 years). CONCLUSIONS: Pediatric intracranial aneurysms are significantly different from adult aneurysms in terms of sex, presentation, location, size, and outcomes. Future prospective studies will better characterize long-term aneurysm recurrence, rebleeds, and de novo aneurysm occurrences. The authors currently favor microsurgical over endovascular treatment for pediatric aneurysms.

Cumulative Damage: Cell Death in Posthemorrhagic Hydrocephalus of Prematurity.

Globally, approximately 11% of all infants are born preterm, prior to 37 weeks' gestation. In these high-risk neonates, encephalopathy of prematurity (EoP) is a major cause of both morbidity and mortality, especially for neonates who are born very preterm (<32 weeks gestation). EoP encompasses numerous types of preterm birth-related brain abnormalities and injuries, and can culminate in a diverse array of neurodevelopmental impairments. Of note, posthemorrhagic hydrocephalus of prematurity (PHHP) can be conceptualized as a severe manifestation of EoP. PHHP impacts the immature neonatal brain at a crucial timepoint during neurodevelopment, and can result in permanent, detrimental consequences to not only cerebrospinal fluid (CSF) dynamics, but also to white and gray matter development. In this review, the relevant literature related to the diverse mechanisms of cell death in the setting of PHHP will be thoroughly discussed. Loss of the epithelial cells of the choroid plexus, ependymal cells and their motile cilia, and cellular structures within the glymphatic system are of particular interest. Greater insights into the injuries, initiating targets, and downstream signaling pathways involved in excess cell death shed light on promising areas for therapeutic intervention. This will bolster current efforts to prevent, mitigate, and reverse the consequential brain remodeling that occurs as a result of hydrocephalus and other components of EoP.