Surveillance protocol for the detection of intracranial abnormalities in premature neonates

Achados de ressonância magnética de encéfalo neonatal: correlação com fatores de risco pré-natais e ultrassonografia transfontanelar

Resumo Objetivo: Avaliar alterações encontradas nas ressonâncias magnéticas (RMs) encefálicas neonatais, correlacionando com a ultrassonografia transfontanelar (USTF), e descrever os principais fatores de risco encontrados. Materiais e Métodos: Foram avaliados exames de 51 pacientes que realizaram RM utilizando protocolo neonatal durante internação hospitalar, correlacionando com resultados da USTF prévia, sendo utilizada, para minimizar as chances de viés, a última USTF realizada. Os dados foram obtidos de prontuário médico e as imagens foram revisadas por médico radiologista especialista em neuroimagem. Resultados: A população foi composta majoritariamente de recém-nascidos prematuros extremos (21; 41,2%) e de extremo baixo peso (22; 43,1%). Foram encontradas alterações em 16 (31,4%) das USTFs e em 30 (58,8%) das RMs, sendo a hemorragia da matriz germinativa o achado mais frequente. Os valores preditivos positivo e negativo da USTF em relação à RM foram de 87% e 54%, respectivamente. Conclusão: A USTF mostrou-se importante na distinção entre os graus de hemorragia da matriz germinativa leve e moderada (I e II) dos graus acentuados (III e IV), sendo considerada um bom exame de rastreio e acompanhamento, principalmente em pacientes mais graves e com fatores de risco.

Alterations on magnetic resonance imaging of the neonatal brain: correlations with prenatal risk factors and transfontanellar ultrasound findings

Abstract Objective: To describe the alterations seen on magnetic resonance imaging (MRI) of the brain in newborns, correlating those alterations with the transfontanellar ultrasound (TFUS) findings, and to describe the main risk factors identified. Materials and Methods: We evaluated the examinations of 51 patients who were submitted to brain MRI with a neonatal protocol during hospitalization. We evaluated the MRI findings and correlated them with previous TFUS findings, using the last TFUS performed in order to minimize the risk of bias. Data were obtained from medical records, and the images were reviewed by a radiologist specializing in neuroimaging. Results: Of the 51 patients evaluated, 21 (41.2%) were extremely preterm infants and 22 (43.1%) were extremely-low-birth-weight infants. Alterations were seen on 16 (31.4%) of the TFUS examinations and on 30 (58.8%) of the brain MRI scans, the most common finding being germinal matrix hemorrhage. The positive and negative predictive values of TFUS in relation to MRI were 87% and 54%, respectively. Conclusion: Because TFUS proved to be capable of distinguishing mild and moderate (grade I and II) germinal matrix hemorrhage from the severe forms (grades III and IV), it can be considered a good tool for screening and follow-up, especially in infants with severe disease and risk factors.

Rate of head ultrasound abnormalities at one month in very premature and extremely premature infants with normal initial screening ultrasound

BACKGROUND

Premature infants are at risk for multiple types of intracranial injury with potentially significant long-term neurological impact. The number of screening head ultrasounds needed to detect such injuries remains controversial.

OBJECTIVE

To determine the rate of abnormal findings on routine follow-up head ultrasound (US) performed in infants born at ≤ 32 weeks' gestational age (GA) after initial normal screening US.

MATERIALS AND METHODS

A retrospective study was performed on infants born at ≤ 32 weeks' GA with a head US at 3-5 weeks following a normal US at 3-10 days at a tertiary care pediatric hospital from 2014 to 2020. Exclusion criteria included significant congenital anomalies, such as congenital cardiac defects necessitating surgery, congenital diaphragmatic hernia or spinal dysraphism, and clinical indications for US other than routine screening, such as sepsis, other risk factors for intracranial injury besides prematurity, or clinical neurological abnormalities. Ultrasounds were classified as normal or abnormal based on original radiology reports. Images from initial examinations with abnormal follow-up were reviewed.

RESULTS

Thirty-three (14.2%) of 233 infants had 34 total abnormal findings on follow-up head US after normal initial US. Twenty-seven infants had grade 1 germinal matrix hemorrhage, and four had grade 2 intraventricular hemorrhage. Two had periventricular echogenicity and one had a focus of cerebellar echogenicity that resolved and was determined to be artifactual.

CONCLUSION

When initial screening head ultrasounds in premature infants are normal, follow-up screening ultrasounds are typically also normal. Abnormal findings are usually limited to grade 1 germinal matrix hemorrhage.

Cranial Ultrasound Screening Protocols for Very Preterm Infants

Cranial ultrasound examinations are routinely performed in very preterm neonates. There is no widespread agreement on the optimal timing of these examinations. This review examines screening protocols and recommendations available for the timing of cranial ultrasound examinations in preterm neonates born before 32 wk of gestation. A systematic search was performed to find published screening protocols, and 18 articles were included in the final review. The protocols varied in their recommendations on timing, although at least one examination in the first week of life was universally recommended. The recommended timing for a "late" or final ultrasound examination was variable, and included at 6 wks of postnatal age, term-equivalent age or hospital discharge. There was no agreement as to whether weekly or fortnightly sequential ultrasound imaging should be performed after the first week of life. Further studies are required to establish an optimal protocol for these very preterm neonates to improve detection and monitoring of brain injuries.

Germinal Matrix-Intraventricular Hemorrhage: A Tale of Preterm Infants

Germinal matrix-intraventricular hemorrhage (GM-IVH) is a common intracranial complication in preterm infants, especially those born before 32 weeks of gestation and very-low-birth-weight infants. Hemorrhage originates in the fragile capillary network of the subependymal germinal matrix of the developing brain and may disrupt the ependymal lining and progress into the lateral cerebral ventricle. GM-IVH is associated with increased mortality and abnormal neurodevelopmental outcomes such as posthemorrhagic hydrocephalus, cerebral palsy, epilepsy, severe cognitive impairment, and visual and hearing impairment. Most affected neonates are asymptomatic, and thus, diagnosis is usually made using real-time transfontanellar ultrasound. The present review provides a synopsis of the pathogenesis, grading, incidence, risk factors, and diagnosis of GM-IVH in preterm neonates. We explore brief literature related to outcomes, management interventions, and pharmacological and nonpharmacological prevention strategies for GM-IVH and posthemorrhagic hydrocephalus.

Disruption and Compensation of Sulcation-based Covariance Networks in Neonatal Brain Growth after Perinatal Injury

Perinatal brain injuries in preterm neonates are associated with alterations in structural neurodevelopment, leading to impaired cognition, motor coordination, and behavior. However, it remains unknown how such injuries affect postnatal cortical folding and structural covariance networks, which indicate functional parcellation and reciprocal brain connectivity. Studying 229 magnetic resonance scans from 158 preterm neonates (n = 158, mean age = 28.2), we found that severe injuries including intraventricular hemorrhage, periventricular leukomalacia, and ventriculomegaly lead to significantly reduced cortical folding and increased covariance (hyper-covariance) in only the early (<31 weeks) but not middle (31-35 weeks) or late stage (>35 weeks) of the third trimester. The aberrant hyper-covariance may drive acceleration of cortical folding as a compensatory mechanism to "catch-up" with normal development. By 40 weeks, preterm neonates with/without severe brain injuries exhibited no difference in cortical folding and covariance compared with healthy term neonates. However, graph theory-based analysis showed that even after recovery, severely injured brains exhibit a more segregated, less integrated, and overall inefficient network system with reduced integration strength in the dorsal attention, frontoparietal, limbic, and visual network systems. Ultimately, severe perinatal injuries cause network-level deviations that persist until the late stage of the third trimester and may contribute to neurofunctional impairment.

L’imagerie cérébrale systématique du nouveau-né prématuré

L’imagerie cérébrale systématique pour déceler les lésions touchant les nouveau-nés prématurés est utilisée pour prédire le pronostic à long terme et déterminer les complications susceptibles de nécessiter une intervention. Même si l’imagerie par résonance magnétique peut être indiquée dans des situations particulières, l’échographie cérébrale est la technique la plus utilisée et demeure la meilleure modalité d’imagerie systématique en raison de sa portabilité et de sa facilité d’accès. L’échographie cérébrale systématique est recommandée pour tous les nouveau-nés venus au monde à 31+6 semaines d’âge gestationnel ou auparavant. Chez les nouveau-nés prématurés venus au monde entre 32+0 et 36+6 semaines d’âge gestationnel l’échographie cérébrale systématique n’est recommandée qu’en présence de facteurs de risque d’hémorragie intracrânienne ou d’ischémie. Il est conseillé d’obtenir une imagerie cérébrale de quatre à sept jours après la naissance pour déceler la plupart des hémorragies de la matrice germinale et des hémorragies intraventriculaires. Il est recommandé de reprendre l’imagerie entre quatre et six semaines de vie pour déceler les lésions de la substance blanche. Chez les nouveau-nés prématurés venus au monde avant 26 semaines d’âge gestationnel, il est recommandé de reprendre l’échographie cérébrale à l’âge équivalant au terme.

Routine imaging of the preterm neonatal brain

Routine brain imaging to detect injuries affecting preterm infants is used to predict long-term outcomes and identify complications that might necessitate an intervention. Although magnetic resonance imaging may be indicated in some specific cases, head ultrasound is the most widely used technique and, because of portability and ease of access, is the best modality for routine imaging. Routine head ultrasound examination is recommended for all infants born at or before 31+6 weeks gestation. For preterm neonates born between 32+0 to 36+6 weeks gestation, routine head ultrasound is recommended only in presence of risk factors for intracranial hemorrhage or ischemia. Brain imaging in the first 7 to 14 days postbirth is advised to detect most germinal matrix and intraventricular hemorrhages. Repeat imaging at 4 to 6 weeks of age is recommended to detect white matter injury.

Neonatal Head Ultrasound: A Review and Update-Part 1: Techniques and Evaluation of the Premature Neonate

Ultrasound of the infant brain has proven to be an important diagnostic tool in the evaluation of neonatal brain morphology and pathology since its introduction in the late 1970s and early 1980s. It is a relatively inexpensive examination that can be performed in the isolette in the neonatal intensive care unit. There is no radiation exposure and no need for sedation. This article will discuss gray scale and Doppler techniques and findings in normal head ultrasounds of premature neonates. It will discuss intracranial pathologies noted in such neonates and their neurodevelopmental outcome.

Critical Shifts in Cerebral White Matter Lipid Profiles After Ischemic-Reperfusion Brain Injury in Fetal Sheep as Demonstrated by the Positive Ion Mode MALDI-Mass Spectrometry

Ischemic-reperfusion (I/R) injury to cerebral white matter during the perinatal period leads to long-term cognitive and motor disabilities in children. Immature white matter oligodendrocytes are especially vulnerable to metabolic insults such as those caused by hypoxic, ischemic, and reperfusion injury. Consequences include an impaired capacity of oligodendrocytes to generate and maintain mature lipid-rich myelin needed for efficient neuronal conductivity. Further research is needed to increase an understanding of the early, possibly reversible myelin-associated pathologies that accompany I/R white matter injury. This experiment characterized I/R time-dependent alterations in cerebral white matter lipid profiles in an established fetal sheep model. Fetal sheep (127 days gestation) were subjected to 30 min of bilateral carotid artery occlusion followed by 4 h (n = 5), 24 h (n = 7), 48 h (n = 3), or 72 h (n = 5) of reperfusion, or sham treatment (n = 5). Supraventricular cerebral white matter lipids were analyzed using the positive ionization mode matrix-assisted laser desorption/ionization mass spectrometry. Striking I/R-associated shifts in phospholipid (PL) and sphingolipid expression with a prominent upregulation of cardiolipin, phosphatidylcholine, phosphatidylinositol monomannoside, sphingomyelin, sulfatide, and ambiguous or unidentified lipids were observed to occur mainly at I/R-48 and normalized or suppressed responses at I/R-72. In fetal sheep, cerebral I/R caused major shifts in white matter myelin lipid composition favoring the upregulated expression of diverse PLs and sphingolipids which are needed to support neuronal membrane, synaptic, metabolic, and cell signaling functions.

Risk factors for intraventricular hemorrhage in premature infants in the central region of Saudi Arabia

Background

Intraventricular hemorrhage (IVH) is a serious complication of premature (<32 weeks) deliveries, especially in very-low-birth-weight (VLBW; <1500 g) neonates. Infants developing severe IVH are more prone to long-term developmental disabilities. Although 62%–79% of women in Saudi Arabia receive antenatal steroids, IVH incidence remains high. We analyzed the risk factors for IVH in preterm VLBW neonates in the central region of Saudi Arabia.

Methods

We included premature infants with IVH (n = 108) and gestational age- and birth weight-matched control group infants (n = 108) admitted to our neonatal intensive care unit. Cases were divided into mild (grades I and II; n = 56) and severe (grades III and IV; n = 52) IVH groups. Association of IVH with risk factors in the first week of life was investigated.

Results

The following risk factors were associated with severe IVH: lack of antenatal steroid administration (P < .001), pulmonary hemorrhage (P = .023), inotrope use (P = .032), neonatal hydrocortisone administration (P = .001), and patent ductus arteriosus (PDA) (P = .005). Multivariable logistic regression analysis revealed the following to be significant: lack of antenatal dexamethasone (adjusted odds ratio [aOR]: 0.219, 95% confidence interval [95% CI] 0.087–0.546), neonatal hydrocortisone administration (aOR: 3.519, 95% CI 1.204–10.281), and PDA (aOR: 2.718, 95% CI 1.024–7.210). Low hematocrit in the first 3 days of life was significantly associated with severe IVH (all P < .01).

Conclusions

Failure to receive antenatal dexamethasone, PDA, hydrocortisone administration for neonatal hypotension, and low hematocrit in the first 3 days of life was associated with severe IVH in VLBW neonates. Clinicians and healthcare policy makers should consider these factors during decision-making.

Predictors of Severe Neurologic Injury on Ultrasound Scan of the Head and Risk Factor-based Screening for Infants Born Preterm

OBJECTIVE

To identify risk factors for severe neurologic injury (intraventricular hemorrhage grade 3 or greater and/or periventricular leukomalacia) diagnosed by ultrasound scan of the head among infants born at 30⁰-32⁶ weeks of gestation and compare different screening strategies.

STUDY DESIGN

This was a retrospective cohort study of infants born at 30⁰-32⁶ weeks or >32⁶ weeks of gestation with a birth weight <1500 g admitted to neonatal intensive care units in the Canadian Neonatal Network from 2011 to 2016. Stepwise logistic regression analysis was used to identify significant risk factors and calculate aORs and 95% CIs. Risk factor-based screening strategies were compared.

RESULTS

The rate of severe neurologic injury was 3.1% among infants screened (285/9221). Significant risk factors included singleton birth (aOR 1.96, 95% CI 1.35-2.85), 5-minute Apgar <7 (aOR 1.81, 95% CI 1.30-2.50), mechanical ventilation on day 1 (aOR 2.65, 95% CI 1.88-3.71), and treatment with vasopressors on day 1 (aOR 3.23, 95% CI 2.19-4.75). Risk categories were low (no risk factor, 1.2%, 25/2137), moderate (singleton with no other risk factor: 1.8%, 68/3678), and high (≥1 risk factor among 5-minute Apgar <7, receipt of vasopressors or mechanical ventilation on day 1: 5.6%, 192/3408). Screening moderate- to high-risk infants identified 91% (260/285) of infants with severe neurologic injury and would require screening fewer infants (1647 infants per year) than screening all infants <33 weeks of gestation (2064 infants screened per year, 93% [265/285] of cases identified).

CONCLUSIONS

Risk factor-based ultrasound scan of the head screening among infants born at 30-32 weeks of gestation could help optimize resources better than gestational age based screening.

A Preliminary Study of Neonatal Cranial Venous System by Color Doppler

Aim

To present anatomic data in the ultrasound planes for the identification of the major veins and the venous sinuses in cerebrum and to establish the sonographic normal reference values for the visualization of vein vessels and vein sinuses and blood flow velocities.

Methods

This study involved 55 healthy full-term neonates for transfontanellar color Doppler sonography. The imaging included both sagittal and coronal planes with LA332E probe, supplemented with PA240 probe as necessary. As low as reasonably achievable (ALARA) principle was obeyed, limiting Doppler exposure time and maximizing signal intensity by increasing gain rather than outputting transducer power settings. The output power was kept at a minimum level consistent with recording an adequate signal. Keeping the newborns in calm state, the total examination time which every neonate required was less than 5 min. All images were stored also in a workstation for further analysis. The description statistics and t-test for statistical analysis were used.

Result

In all studied cases (100% cases), subependymal veins (SV), internal cerebral veins (ICV), Galen vein (GV), straight sinus (SS), superior sagittal sinus (SSS), and transverse sinuses (TS) were visualized. The visualization percentages of inferior sagittal sinus (ISS) or basal veins/Rosenthal veins (BV/RV) were lower than 100%. Based on vessel visualization percentage from high to low, the vessels were ordered as follows: SV, ICV, BV, SS, TS, ISS, and SSS. In SSS and TS, the pulsation percentage was 100%. The descending percentages of vessel pulsation were noted in SS, BV, ICV, and SV. On the basis of the mean of maximum velocities of the vessels from low to high, the vessels were ordered as follows: ISS, BV-L, BV-R, ICV-R, ICV-L, SV-L, SV-R, SSS, TS-L, TS-R, and SS.

Conclusion

The measurements percent of visualization of cerebral deep veins was higher than the percent of cerebral venous sinuses. The pulsation percent of measurement and the velocities of cerebral venous sinuses were absolutely higher than the cerebral deep venous system. The pairs of vascular blood flow velocities were nonsignificantly different from one another.

Pattern of intracranial findings detected on magnetic resonance imaging in surviving infants born before 29 weeks of gestation

Despite the positive survival trend in infants born prematurely, the risk for development of intracranial lesions has remained unchanged. However, there are limitations to our understanding of the pattern of the magnetic resonance imaging (MRI) -detected brain pathology in the preterm infants surviving to discharge. The present study outlines the type of intracranial lesions and factors allied with the neonatal brain hemorrhage (NBH) and white matter injury (WMI) seen on MRI at term-equivalent age or close to discharge in infants born before 29 weeks of gestation. We obtained demographic and clinical data, and reports of serial cranial ultrasound (CUS) performed during first month of life and qualitative MRI at term-equivalent age or close to discharge. Statistical comparison was conducted with respect to the MRI results that were classified as normal, WMI, and NBH using univariate and logistic regression analysis. One hundred and ninety three infants with MRI at term-equivalent age or close to discharge were included in final analysis. They were less mature and had a higher prevalence of pathological findings on CUS as compared with 249 other survivors born with gestational ages less than 29 weeks during the assigned study period. MRI was normal in 72.5% [95% Confidence Interval (95% CI 65.9%-78.4%)], showed WMI in 9.8% (95%CI 6.4%-14.9%) and NBH in 17.6% (95%CI 12.9–23.6) of the studied infants. Intracranial hemorrhages had also been reported in 42.2% of the infants with WMI. Except for moderate agreement with prior CUS results, no other factors were associated with the MRI detected pathological findings. In general, the likelihood for detection of WMI and NBH on MRI at term-equivalent age or close to discharge was reduced by approximately 80% and 70%, respectively if the serial CUS had not shown any abnormalities during the first month of life.

Rapid Alterations in Cerebral White Matter Lipid Profiles After Ischemic-Reperfusion Brain Injury in Fetal Sheep as Demonstrated by MALDI-Mass Spectrometry

BACKGROUND

Perinatal ischemia-reperfusion (I/R) injury of cerebral white matter causes long-term cognitive and motor disabilities in children. I/R damages or kills highly metabolic immature oligodendroglia via oxidative stress, excitotoxicity, inflammation, and mitochondrial dysfunction, impairing their capacity to generate and maintain mature myelin. However, the consequences of I/R on myelin lipid composition have not been characterized.

OBJECTIVE

This study utilized matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to assess alterations in cerebral supraventricular white matter myelin lipid profiles in a fetal sheep model of perinatal I/R.

METHODS

Fetal sheep (127 days gestation) were studied after 30 minutes of bilateral carotid artery occlusion followed by 4 (n = 5), 24 (n = 7), 48 (n = 3), or 72 (n = 5) hours of reperfusion, or sham treatment (n = 5). White matter lipids were analyzed by negative ion mode MALDI-MS.

RESULTS

Striking I/R-associated shifts in phospholipid and sphingolipid expression occurred over the 72-hour time course with most responses detected within 4 hours of reperfusion and progressing at the 48- and 72-hour points. I/R decreased expression of phosphatidic acid and phosphatidylethanol amine and increased phosphatidylinositol, sulfatide, and lactosylceramide.

CONCLUSIONS

Cerebral I/R in mid-gestation fetal sheep causes rapid shifts in white matter myelin lipid composition that may reflect injury, proliferation, or recovery of immature oligodendroglia.

Features of serial cranial ultrasound detected neuropathology in very preterm infants

BACKGROUND

The purpose of this study was to identify the pattern and factors associated with changes in cranial ultrasound (CUS) -detected findings in infants born at or less than 28 weeks of gestation.

METHODS

We compared readings of CUS performed at the end of the first week of life and at 4-5 weeks of age. Alteration of CUS findings was classified as: (i) unchanged, if no deviation was detected (Group 1); (ii) worsening, if there were new findings (Group 2); and (iii) improvement, if there was normalization or reduction in severity (Group 3). Descriptive statistics, multivariate controlled logistic regression, and kappa (k) statistics with 95% Confidence Interval (95% CI) were reported.

RESULTS

Among 510 studied infants, 82.3% (95% CI 78.8-85.4) were in Group 1, 10.0% (95% CI 7.7-12.9) in Group 2, and 7.7% (95% CI 5.7-10.3) in Group 3. Overall agreement between the two scans was moderate (k 0.62; 95% CI 0.55-0.69). Worsening of CUS findings was associated with neonatal morbidities independently from gestational age and birth weight. The probability for worsening of CUS findings was higher in infants with an initial diagnosis of intraventricular hemorrhage (IVH) grade 2, than in those reported as no pathology/IVH grade 1 (Odds Ratio 5.79; 95% CI 2.42-13.91) or IVH grade 3-4 (Odds Ratio 3.81; 95% CI 1.10-13.21).

CONCLUSIONS

In very preterm born infants, the initial CUS findings in combination with neonatal morbidities can help predict the brain lesions that are seen at the end of the first month of life and could be useful in their clinical management.

Cerebral near-infrared spectroscopy monitoring for prevention of brain injury in very preterm infants

BACKGROUND

Cerebral injury and long-term neurodevelopmental impairment is common in extremely preterm infants. Cerebral near-infrared spectroscopy (NIRS) enables continuous estimation of cerebral oxygenation. This diagnostic method coupled with appropriate interventions if NIRS is out of normal range (that is cerebral oxygenation within the 55% to 85% range) may offer benefits without causing more harms. Therefore, NIRS coupled with appropriate responses to abnormal findings on NIRS needs assessment in a systematic review of randomised clinical trials and quasi-randomised studies.

OBJECTIVES

To evaluate the benefits and harms of interventions that attempt to alter cerebral oxygenation guided by cerebral NIRS monitoring in order to prevent cerebral injury, improve neurological outcome, and increase survival in preterm infants born more than 8 weeks preterm.

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 8), MEDLINE via PubMed (1966 to 10 September 2016), Embase (1980 to 10 September 2016), and CINAHL (1982 to 10 September 2016). We also searched clinical trial databases, conference proceedings, and the reference lists of retrieved articles for randomised clinical trials and quasi-randomised studies.

SELECTION CRITERIA

Randomised clinical trials and quasi-randomised clinical studies comparing continuous cerebral NIRS monitoring for at least 24 hours versus blinded NIRS or versus no NIRS monitoring.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected, assessed the quality of, and extracted data from the included trials and studies. If necessary, we contacted authors for further information. We conducted assessments of risks of bias; risks of design errors; and controlled the risks of random errors with Trial Sequential Analysis. We assessed the quality of the evidence with GRADE.

MAIN RESULTS

One randomised clinical trial met inclusion criteria, including infants born more than 12 weeks preterm. The trial employed adequate methodologies and was assessed at low risk of bias. One hundred and sixty-six infants were randomised to start continuous cerebral NIRS monitoring less than 3 hours after birth until 72 hours after birth plus appropriate interventions if NIRS was out of normal range according to a guideline versus conventional monitoring with blinded NIRS. There was no effect of NIRS plus guideline of mortality until term-equivalent age (RR 0.50, 95% CI 0.29 to 1.00; one trial; 166 participants). There were no effects of NIRS plus guideline on intraventricular haemorrhages: all grades (RR 0.93, 95% CI 0.65 to 1.34; one trial; 166 participants); grade III/IV (RR 0.57, 95% CI 0.25 to 1.31; one trial; 166 participants); and cystic periventricular leukomalacia (which did not occur in either group). Likewise, there was no effect of NIRS plus guideline on the occurrence of a patent ductus arteriosus (RR 1.96, 95% CI 0.94 to 4.08; one trial; 166 participants); chronic lung disease (RR 1.27, 95% CI 0.94 to 1.50; one trial; 166 participants); necrotising enterocolitis (RR 0.83, 95% CI 0.33 to 1.94; one trial; 166 participants); and retinopathy of prematurity (RR 1.64, 95% CI 0.75 to 3.00; one trial; 166 participants). There were no serious adverse events in any of the intervention groups. NIRS plus guideline caused more skin marks from the NIRS sensor in the control group than in the experimental group (unadjusted RR 0.31, 95% CI 0.10 to 0.92; one trial; 166 participants). There are no data regarding neurodevelopmental outcome, renal impairment or air leaks.The quality of evidence for all comparisons discussed above was assessed as very low apart from all-cause mortality and adverse events: these were assessed as low and moderate, respectively. The validity of all comparisons is hampered by a small sample of randomised infants, risk of bias due to lack of blinding, and indirectness of outcomes.

AUTHORS' CONCLUSIONS

The only eligible randomised clinical trial did not demonstrate any consistent effects of NIRS plus a guideline on the assessed clinical outcomes. The trial was, however, only powered to detect difference in cerebral oxygenation, not morbidities or mortality. Our systematic review did not reach sufficient power to prove or disprove effects on clinical outcomes. Further randomised clinical trials with low risks of bias and low risks of random errors are needed.

Neurosonography: Assessing the Premature Infant

Neurosonography has proven to be helpful in neonatal brain diagnosis. Premature infants are at great risk for intraventricular hemorrhage and periventricular leukomalacia, key abnormalities affecting developmental outcome. Here we discuss technique, anatomy, variants and key points for diagnosis.

Thromboelastographic profiles of the premature infants with and without intracranial hemorrhage at birth: a pilot study

OBJECTIVE

To delineate thromboelastographic profiles of the premature infants with and without intracranial hemorrhage during the first 21 days of life.

METHODS

In this study, 49 premature infants (24 female; 25 male) were consecutively admitted at our neonatal intensive care unit during a 6 months period were subject to thromboelastography and standard coagulation assessments at birth and weekly up to 21 days. Sixteen out of 49 infants developed intracranial hemorrhage at birth.

RESULTS

The test results of 127/196 were considered eligible for analysis. Overall significant changes of the main thromboelastographic parameters were observed shortly after birth. Newborns with intracranial hemorrhage showed increased thromboelastogram-defined thrombin generation (shorter R and time to maximum amplitude times) from birth onward, suggesting a hypercoagulable state. No significant differences concerning thromboelastographic and coagulation assays parameters were found at birth between infants with and without intracranial hemorrhage, except for higher plasma D-Dimer concentration (p = 0.002) in the former infants. Finally, a positive correlation between clot lysis time and gestational age (Spearman's rho = 0.502, p = 0.002) was observed.

CONCLUSIONS

Thromboelastographic profiles of the premature infants suggest an effective hemostatic function during the first post-natal weeks. Further study is needed to determine whether thromboelastography may be more useful than coagulation assays to reflect the bleeding risk of the premature infants.

Brain Surface Heating After Exposure to Ultrasound: An Analysis Using Thermography

Ultrasound is the imaging modality of choice to monitor brain pathologies in neonates after complicated deliveries. Animal studies have indicated that ultrasound may cause heating of brain tissues. To date, no study has explored brain surface heating by ultrasound during clinically relevant exposure. Hence, we investigated heating effects of B-mode and pulsed Doppler (PD) mode on ex vivo lamb brains using thermography. Five brains were scanned for 5 min in B-mode or for 3 min, 1 min, 30 s or 15 s in PD mode. Brain surface temperature was measured pre- and post-exposure using thermography. The highest mean temperature increase was recorded by B-mode (3.82 ± 0.43°C). All five PD exposure protocols were associated with surface temperature increases of 2.1-2.7°C. These outcomes highlight for the first time that B-mode ultrasound can contribute to brain surface heating during a routine cranial scan. Scan duration should be minimised whenever possible.

Cinegraphic versus Combined Static and Cinegraphic Imaging for Initial Cranial Ultrasound Screening in Premature Infants

BACKGROUND

Cranial ultrasound is an essential screening and diagnostic tool in the care of neonates and is especially useful in the premature population for evaluation of potential germinal matrix/intraventricular hemorrhage (GM/IVH). There are typically two screening examinations, with the initial cranial sonography performed between 3 days and 14 days after birth, usually consisting of a series of static images plus several cinegraphic sweeps.

OBJECTIVE

Our primary goal was to assess whether cinegraphic sweeps alone are as accurate for diagnosing neurological abnormalities as combined static and cinegraphic imaging in the initial cranial US evaluation of premature infants. Our secondary goal was to establish the difference in time required to perform these two examinations.

MATERIALS AND METHODS

We retrospectively obtained 140 consecutive initial cranial US screening studies of premature infants. Three pediatric radiologists blinded to patient data read cinegraphic images alone and also combined (dual) imaging sets for a subset of subjects, recording findings for seven disease processes: germinal matrix/intraventricular hemorrhage (GM/IVH), right or left side; periventricular leukomalacia (PVL); choroid plexus cyst; subependymal cyst; cerebral and cerebellar infarction or hemorrhage; posterior fossa hemorrhage or infarction, and extra-axial hemorrhage. Separately, we compared retrospective dual imaging acquisition time against prospectively collected cinegraphic imaging time for premature infants undergoing initial cranial US evaluation.

RESULTS

Equivalence testing demonstrated no difference in equivalency between initial cranial US screening using cinegraphic evaluation alone and dual imaging for GM/IVH, cerebral and cerebellar infarct or hemorrhage, and subependymal cyst (all P < 0.05). For PVL and choroid plexus cyst, cinegraphic imaging and dual imaging did not demonstrate equivalence (P > 0.05). Cinegraphic images were obtained in less than one-third of the time required for dual imaging.

CONCLUSION

For the diagnoses that are critical to establish at initial screening (GM/IVH, cerebral and cerebellar infarct or hemorrhage) initial cranial US screening using cinegraphic sweeps was equivalent to dual imaging. Cinegraphic imaging required significantly less time to perform than dual imaging. We suggest that performance of cranial US screening using cinegraphic imaging alone is a potentially advantageous option in the initial evaluation of the premature neonate.

Do normal head ultrasounds need repeating in infants less than 30 weeks gestation?

OBJECTIVE

Current head ultrasound (HUS) screening recommendations in preterm infants often include a repeat HUS, regardless of initial findings. The objective of this study is to determine the rate of subsequent severe intraventricular hemorrhage (IVH), ventriculomegaly (VM), or periventricular leukomalacia (PVL) among infants < 30 weeks gestation (EGA) with a normal HUS at day of life (DOL) 4-10.

METHODS

Retrospectively collected data were analyzed for all infants < 30 weeks EGA cared for in one NICU from 1 January 2010 to 31 August 2014. Infants with severe congenital anomalies were excluded. We reviewed the first three HUSs and last documented HUS. Severe IVH was defined as > Papile grade 2 and significant interval HUS change was defined as development of severe IVH, PVL, or VM.

RESULTS

Of the 383 infants who had an initial screening HUS between DOL 4 and 10, 258 (67%) were initially normal and repeat screening was performed in 228 of these. None developed severe IVH on follow-up HUS. One infant developed VM secondary to GBS meningitis, and one developed echogenicity concerning for PVL that later resolved.

CONCLUSIONS

Among very preterm infants with a normal HUS between DOL 4 and 10, routine follow-up HUS is unlikely to identify a significant change.

Screening Cranial Imaging at Multiple Time Points Improves Cystic Periventricular Leukomalacia Detection

OBJECTIVE

The aim of this study is to determine whether the cystic periventricular leukomalacia (cPVL) detection rate differs between imaging studies performed at different time points.

DESIGN

We retrospectively reviewed the prospectively collected data of 31,708 infants from the NICHD Neonatal Research Network. Inclusion criteria were infants < 1,000 g birth weight or < 29 weeks' gestational age who had cranial imaging performed using both early criterion (cranial ultrasound [CUS] < 28 days chronological age) and late criterion (CUS, magnetic resonance imaging, or computed tomography closest to 36 weeks postmenstrual age [PMA]). We compared the frequency of cPVL diagnosed by early and late criteria.

RESULTS

About 664 (5.2%) of the 12,739 infants who met inclusion criteria had cPVL using either early or late criteria; 569 using the late criterion, 250 using the early criterion, and 155 patients at both times. About 95 (14.3%) of 664 cPVL cases seen on early imaging were no longer visible on repeat screening closest to 36 weeks PMA. Such disappearance of cPVL was more common in infants < 26 weeks' gestation versus infants of 26 to 28 weeks' gestation (18.5 vs. 11.5%; p = 0.013).

CONCLUSIONS

Cranial imaging at both < 28 days chronological age and closest to 36 weeks PMA improves cPVL detection, especially for more premature infants.

Outcomes for extremely premature infants

Premature birth is a significant cause of infant and child morbidity and mortality. In the United States, the premature birth rate, which had steadily increased during the 1990s and early 2000s, has decreased annually for 7 years and is now approximately 11.39%. Human viability, defined as gestational age at which the chance of survival is 50%, is currently approximately 23 to 24 weeks in developed countries. Infant girls, on average, have better outcomes than infant boys. A relatively uncomplicated course in the intensive care nursery for an extremely premature infant results in a discharge date close to the prenatal estimated date of confinement. Despite technological advances and efforts of child health experts during the last generation, the extremely premature infant (less than 28 weeks gestation) and extremely low birth weight infant (<1000 g) remain at high risk for death and disability with 30% to 50% mortality and, in survivors, at least 20% to 50% risk of morbidity. The introduction of continuous positive airway pressure, mechanical ventilation, and exogenous surfactant increased survival and spurred the development of neonatal intensive care in the 1970s through the early 1990s. Routine administration of antenatal steroids during premature labor improved neonatal mortality and morbidity in the late 1990s. The recognition that chronic postnatal administration of steroids to infants should be avoided may have improved outcomes in the early 2000s. Evidence from recent trials attempting to define the appropriate target for oxygen saturation in preterm infants suggests arterial oxygen saturation between 91% and 95% (compared with 85%-89%) avoids excess mortality; however, final analyses of data from these trials have not been published, so definitive recommendations are still pending. The development of neonatal neurocritical intensive care units may improve neurocognitive outcomes in this high-risk group. Long-term follow-up to detect and address developmental, learning, behavioral, and social problems is critical for children born at these early gestational ages.The striking similarities in response to extreme prematurity in the lung and brain imply that agents and techniques that benefit one organ are likely to also benefit the other. Finally, because therapy and supportive care continue to change, the outcomes of extremely low birth weight infants are ever evolving. Efforts to minimize injury, preserve growth, and identify interventions focused on antioxidant and anti-inflammatory pathways are now being evaluated. Thus, treating and preventing long-term deficits must be developed in the context of a "moving target."

Time efficiency and diagnostic agreement of 2-D versus 3-D ultrasound acquisition of the neonatal brain

The purpose of this study was to compare acquisition time efficiency and diagnostic agreement of neonatal brain ultrasound (US) scans obtained with a 3-D volume US acquisition protocol and the conventional 2-D acquisition protocol. Ninety-one consecutive premature neonatal brain ultrasound scans were prospectively performed on 59 neonates with the conventional 2-D acquisition protocol. Immediately after the 2-D study, a coronal 3-D ultrasound volume was acquired and later reconstructed into axial and sagittal planes. All 59 neonates were imaged in the neonatal intensive care unit to rule out intracranial hemorrhage. Total time for 2-D and 3-D acquisition protocols was recorded, and a two-tailed t-test was used to determine if study durations differed significantly. One pediatric neuroradiologist reviewed the reformatted 3-D images, tomographic ultrasound images. Results were compared with the clinical interpretation of the 2-D conventional study. The mean scanning time for the 2-D US acquisition protocol was 10.56 min (standard deviation [SD] = 7.11), and that for the 3-D volume US acquisition protocol was 1.48 min (SD = 0.59) (p ≤ 0.001). Inter-observer agreement revealed k values of 0.84 for hydrocephalus, 0.80 for germinal matrix hemorrhage/intraventricular hemorrhage, 0.74 for periventricular leukomalacia and 0.91 for subdural collection, hence near-perfect to substantial agreement between imaging protocols. There was a significant decrease in acquisition time for the 3-D volume ultrasound acquisition protocol compared with the conventional 2-D US protocol (p = <0.001), without compromising the diagnostic quality compared with a conventional 2-D US imaging protocol.

Usefulness of parent-completed ASQ for neurodevelopmental screening of preterm children at five years of age

INTRODUCTION

Preterm children are at greater risk of developmental impairment and require close follow-up for early and optimal medical care. Our goal was to examine use of the parent-completed Ages and Stages Questionnaire (ASQ) as a screening tool for neurodevelopmental disabilities in preterm infants at five years of age.

PATIENTS AND METHODS

A total of 648 preterm children (<35 weeks gestational age) born between 2003 and 2004 and included in the regional Loire Infant Follow-up network were evaluated at five years of age. ASQ was compared with two validated tools (Intelligence Quotient and Global School Adaptation Score) and the impact of maternal education on the accuracy of this questionnaire was assessed.

RESULTS

Overall ASQ scores for predicting full-scale IQ<85 and GSA score produced an area under the receiver operating characteristic curve of 0.73±0.03 and 0.77±0.03, respectively. An ASQ cut-off value of 285 had optimal discriminatory power for identifying children with IQ scores<85 and GSA scores in the first quintile. ASQ values<285 were significantly associated with a higher risk of non-optimal neurologic outcomes (sensitivity of 0.80, specificity of 0.54 for IQ<85). ASQ values>285 were not distinctive for mild delay or normal development. In children with developmental delay, no difference was found when ASQ scores according to maternal education levels were analyzed.

CONCLUSIONS

ASQ at five years is a simple and cost-effective tool that can detect severe developmental delay in preterm children regardless of maternal education level, while its capacity to identify children with mild delay appears to be more limited.

Restrictive guideline reduces platelet count thresholds for transfusions in very low birth weight preterm infants

BACKGROUND AND OBJECTIVES

Platelet transfusions are performed almost entirely according to expert experience. This study assessed the effectiveness of a restrictive guideline to reduce platelet transfusions in preterm infants.

METHODS

A retrospective cohort of preterm infants with a birth weight of <1500 g had been born in 2 periods. In Period 1, a transfusion was indicated for a platelet count of <50,000/ml in clinically stable neonates or <100,000/ml in bleeding or clinically unstable infants. In Period 2, the indications were restricted to <25,000/ml in clinically stable neonates, or <50,000/ml in newborns who were either on mechanical ventilation, subject to imminent invasive procedures, within 72 h following a seizure, or extremely premature and <7 days old. A count of <100,000/ml was indicated for bleeding or major surgery.

RESULTS

Periods 1 and 2 comprised 121 and 134 neonates, respectively. The rates of ventricular haemorrhage and intrahospital death were similar in both periods. The percentage of transfused infants, the odds of receiving a platelet transfusion, the mean platelet count before transfusion and the percentage of transfusions with a platelet count >50,000/ml were greater in Period 1. Among thrombocytopenic neonates, the percentage of transfused neonates and the number of transfusions were similar in both groups.

CONCLUSION

The restrictive guideline for platelet transfusions reduced the platelet count thresholds for neonatal transfusions without increasing the rate of ventricular haemorrhage.

Neurocritical care for neonates

OPINION STATEMENT

Neurocritical care is an emerging subspecialty that combines expertise in neurology, critical care medicine, neuroradiology, and neurosurgery. Increasing evidence from the adult literature suggests that specialized neurocritical care can lead to improved outcomes following acute brain injury. Critically ill neonates with neurologic conditions may also benefit from specialized neurocritical care. Adherence to guidelines and managing patients in intensive care nurseries with dedicated, multidisciplinary neurocritical care personnel may optimize outcomes. This goal may be achieved by more quickly recognizing neurologic impairment, preventing secondary brain injury by maintaining basic physiologic functions, and rapidly implementing therapies. Nurseries that care for neonates with suspected acute brain injury should be prepared to adequately support multiorgan involvement, monitor the brain to detect seizures, evaluate for brain injury using MRI, and follow development through school age.

Infantile posthemorrhagic hydrocephalus

INTRODUCTION

Intraventricular/germinal matrix hemorrhage affects 7-30% of premature neonates, 25-80% of whom (depending on the grade of the hemorrhage) will develop hydrocephalus requiring shunting. Predisposing factors are low birth weight and gestational age.

MATERIAL

There is increasing evidence for the role of TGF-β1 in the pathogenesis of hydrocephalus, but attempts to develop treatment modalities to clear the cerebrospinal fluid (CSF) from blood degradation products have not succeeded so far. Ultrasound is a valuable screening tool for high-risk infants and magnetic resonance imaging is increasingly utilized to differentiate progressive hydrocephalus from ex vacuo ventriculomegaly, evaluate periventricular parenchymal damage, decide on the surgical treatment of hydrocephalus, and follow up these patients in the long term. Treatment of increasing ventriculomegaly and intracranial hypertension in the presence of hemorrhagic CSF can involve a variety of strategies, all with relative drawbacks, aiming to drain the CSF while gaining time for it to clear and the neonate to reach term and become a suitable candidate for shunting. Eventually, patients with progressive ventriculomegaly causing intracranial hypertension, who have reached term and their CSF has cleared from blood products, will need shunting.

CONCLUSION

Cognitive long-term outcome is influenced more by the effect of the initial hemorrhage and other perinatal events and less by hydrocephalus, provided that this has been addressed timely in the early postnatal period. Shunting can have many long-term side effects due to mechanical complications and overdrainage. In particular, patients with posthemorrhagic hydrocephalus are more susceptible to multiloculated hydrocephalus and encysted fourth ventricle, both of which are challenging to treat.

Diagnosis of an intraventricular hemorrhage by a pediatric emergency medicine attending using point-of-care ultrasound: a case report

For the past 2 decades, point-of-care ultrasound (POCU) has been increasingly performed in adult emergency medicine for a variety of indications. However, the incorporation of POCU into pediatric emergency medicine has been much slower. Cranial ultrasound is an integral part in neonatology and is routinely used to diagnose intraventricular hemorrhage (IVH). Although cranial ultrasound is not considered a core emergency ultrasound application in the 2008 American College of Emergency Physicians ultrasound guidelines, this novel approach may prove beneficial in the emergency department (ED) setting. We report a case of a 16-day-old male that presented to the pediatric ED with fussiness and found to be anemic. An IVH was diagnosed for the first time using POCU by a pediatric ED attending. Sonographic characteristics of an IVH may be helpful in the prompt diagnosis of this condition, thereby reducing morbidity and mortality and improving the final outcome.

Early identification of the risk for free radical-related diseases in preterm newborns

BACKGROUND

Despite recent advances in preterm newborns healthcare, perinatal pathologies and disabilities are increasing. Oxidative stress (OS) is determinant for the onset of an unbalance between free radicals (FRs) production and antioxidant systems which plays a key role in pathogenesis of pathologies such as retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), grouped as 'free radical-related diseases' (FRD).

AIM

This study tests the hypothesis that OS markers levels in cord blood may predict the onset of FRD pathologies.

PATIENTS AND METHODS

168 preterm newborns of GA: 24-32weeks (28.09+/-1.99); and BW: 470-2480 gr (1358.11+/-454.09) were consecutively recruited. Markers of potential OS risk (non-protein bound iron, NPBI; basal superoxide anion, BSA; under stimulation superoxide anion, USSA) and markers of OS-related damage (total hydroperoxides, TH; advanced oxidation protein products, AOPP) were assessed in cord blood. Associations between FRD onset and OS markers were checked through inferential analysis (univariate logistic regression).

RESULTS

The development of FRD was significantly associated to high cord blood levels of TH, AOPP and NPBI (respectively p=0.000, OR=1.025, 95%CI=1.013-1.038; p=0.014, OR=1.092, 95%CI=1.018-1.172; p=0.007, OR=1.26995%CI=1.066-1.511).

CONCLUSIONS

Elevated levels of TH, AOPP and, above all, NPBI, in cord blood are associated with increased risk for FRD. OS markers allow the early identification of infants at risk for FRD because of perinatal oxidant exposure. This can be useful in devising strategies to prevent or ameliorate perinatal outcome.

Neuroimaging in very preterm infants

Cranial ultrasonography (cUS) and MRI are the preferred modalities used to image the neonatal brain. Both have their specific contributions and advantages. A neuroimaging study, including sequential cUS and single MRI, was performed in a cohort of very preterm infants (gestational age <32 weeks). The major aims were: to study brain imaging findings and to assess the incidences of brain abnormalities and the relationship between brain abnormalities and perinatal clinical parameters; to compare cUS and MRI findings; to describe imaging findings of the thalami and basal ganglia; and to study the reliability of cUS for detection of (diffuse) white matter injury. Patients & methods: Very preterm infants, born during a 1.5-year period, were eligible if there were no exclusion criteria (i.e., metabolic and genetic disorders, or infections and/or congenital malformations of the CNS). Sequential cUS was performed from admission until discharge and on the day of the MRI following a standardized protocol. MRI (3 Tesla) was performed around or shortly after term equivalent age (TEA). Results: A total of 133 infants were included. The mean number of cUS scans per infant was 8.3 (range: 2–23). MRI was performed in 113 infants at a mean postmenstrual age of 44.7 weeks (range: 40.0–55.9). During admission we found periventricular echodensities and intraventricular hemorrhage in 80 and 30% of infants, respectively – both significantly associated with male gender. The incidence of lenticulo striate vasculopathy (LSV) was 19%. Around TEA, ventricular dilatation and widening of extracerebral spaces were frequent findings. In addition, MRI showed punctate white matter lesions and diffuse excessive high-signal intensity. MRI detected subtle white matter lesions more effectively, whereas cUS was better for the detection of LSV, calcifications and germinolytic and plexus cysts. Diffuse, subtle echogenicity of the basal ganglia and thalami was observed in the majority of infants with normal MRI findings in this area. Focal deep gray matter lesions were only rarely encountered. Conclusions: In very preterm infants, frequent, sequential cUS is an excellent tool to image and follow the brain throughout the neonatal period and detects some lesions and transient changes more effectively than MRI. Single MRI provides invaluable and detailed additional information on the growth and development of, and injury to, the brain. Sequential cUS throughout the neonatal period and a single MRI around TEA are therefore warranted. Bilateral, diffuse and subtle echogenicity in the deep gray matter on cUS probably reflects (normal) maturational processes in the immature brain. With the exception of LSV, focal lesions in the deep gray matter are rare and need to be distinguished from benign phenomena in the deep gray matter. Sequential high-quality cUS during the neonatal period predicts severe white matter injury, but is less predictive of mild-to-moderate white matter injury around TEA.

Neonatal Intracranial Ischemia and Hemorrhage : Role of Cranial Sonography and CT Scanning

OBJECTIVE

To evaluate the role of cranial sonography and computed tomography in the diagnosis of neonatal intracranial hemorrhage and hypoxic-ischemic injury in an Indian set-up.

METHODS

The study included 100 neonates who underwent cranial sonography and computed tomography (CT) in the first month of life for suspected intracranial ischemia and hemorrhage. Two observers rated the images for possible intracranial lesions and a kappa statistic for interobserver agreement was calculated.

RESULTS

There was no significant difference in the kappa values of CT and ultrasonography (USG) for the diagnosis of germinal matrix hemorrhage/intraventricular hemorrhage (GMH/IVH) and periventricular leucomalacia (PVL) and both showed good interobserver agreement. USG, however detected more cases of GMH/IVH (24 cases) and PVL (19) cases than CT (22 cases and 16 cases of IVH and PVL, respectively). CT had significantly better interobserver agreement for the diagnosis of hypoxic ischemic injury (HII) in term infants and also detected more cases (33) as compared to USG (18). CT also detected 6 cases of extraaxial hemorrhages as compared to 1 detected by USG.

CONCLUSION

USG is better modality for imaging preterm neonates with suspected IVH or PVL. However, USG is unreliable in the imaging of term newborns with suspected HII where CT or magnetic resonance image scan is a better modality.

The relationship between systemic hemodynamic perturbations and periventricular-intraventricular hemorrhage--a historical perspective

Periventricular-intraventricular hemorrhage (PV-IVH) remains the major cause of injury to the developing brain. Predisposing factors include a germinal matrix with an immature vasculature, a pressure passive cerebral circulation, and hemodynamic perturbations in sick premature infants. Intact cerebral autoregulation has been documented in stable premature infants; however, it functions within a limited blood pressure range and is likely to be absent in the sick hypotensive infant, which increases the risk for PV-IVH with perturbations in blood pressure. The risk for PV-IVH is markedly increased in the absence of antenatal glucocorticoid exposure in the intubated low birthweight infant <1000 g with respiratory distress syndrome; +/- other complications. Although surfactant administration reduces the severity of respiratory distress syndrome, it has not led to a reduction in PV-IVH. Early postnatal administration of indomethacin has been associated with a reduction in PV-IVH, although this has not translated into long-term neurocognitive benefits.

Brain imaging findings in very preterm infants throughout the neonatal period: part I. Incidences and evolution of lesions, comparison between ultrasound and MRI

This study describes the incidence and evolution of brain imaging findings in very preterm infants (GA<32 weeks), assessed with sequential cranial ultrasound (cUS) throughout the neonatal period and MRI around term age. The accuracy of both tools is compared for findings obtained around term. Periventricular echodensities and intraventricular haemorrhage were the most frequent cUS findings during admission. Frequent findings on both cUS and MRI around term included ventricular dilatation, widened extracerebral spaces, and decreased cortical complexity. MRI additionally showed punctate white matter lesions and diffuse and excessive high signal intensity, but did not depict lenticulostriate vasculopathy and calcifications, and was less reliable for germinolytic and plexus cysts. cUS detected most abnormalities that have been associated with abnormal neurodevelopmental outcome.

Neuropsychological screening of a group of preterm twins: comparison with singletons

OBJECTS

Perform neuropsychological screening of a group of preterm twins without major brain pathology and compare it with a control group of similarly preterm children born as singletons.

MATERIALS AND METHODS

Twenty-three preterm twins born at fewer than 32 weeks of gestation were tested for rapid evaluation of cognitive functions at the age of 4 years. The tests evaluated language, non-verbal performances, learning and attention deficit disorders. Cognitive profiles were established. Links between perinatal factors, clinical follow-up and cognitive outcome were investigated. Their cognitive outcome was then compared with the cognitive outcome of 31 preterm singletons with the same gestational periods.

CONCLUSION

The twins' neuropsychological outcome was not more marked than that of the singletons. Birth weight discordance and chorionicity were the only predictive perinatal factors with worse outcome in the twin population.

Neuroimaging and neurodevelopmental outcomes in preterm infants

Imaging of the preterm infant brain has advanced dramatically beyond the earliest era of transillumination. Computed tomography (CT), a crucial innovation during the early 1970s, allowed noninvasive visualization of intracerebral lesions, particularly hemorrhage. The capability to document brain injury in the preterm infant led to better clarification of links to developmental outcomes. With the development of cranial ultrasound (CUS), and more recently, magnetic resonance imaging (MRI), CT is used rarely for imaging the brain of preterm infants. Despite extensive experience with neonatal neuroimaging, significant questions still remain. Substantial controversies exist pertaining to when and how neuroimaging should be performed and how images should be interpreted.

Clinical data predict neurodevelopmental outcome better than head ultrasound in extremely low birth weight infants

OBJECTIVE

To determine the relative contribution of clinical data versus head ultrasound scanning (HUS) in predicting neurodevelopmental impairment (NDI) in extremely low birth weight infants.

STUDY DESIGN

A total of 2103 extremely low birth weight infants (<1000 g) admitted to a National Institute of Child Health and Human Development Neonatal Research Network center who underwent HUS within the first 28 days, a repeat one around 36 weeks' postmenstrual age, and neurodevelopmental assessment at 18 to 22 months corrected age were selected. Multivariate logistic regression models were developed with clinical or HUS variables. The primary outcome was the predictive abilities of the HUS performed before 28 days after birth and closer to 36 weeks postmenstrual age, either alone or in combination with "Early" and "Late" clinical variables.

RESULTS

Models with clinical variables alone predicted NDI better than models with only HUS variables at both 28 days and 36 weeks (both P < .001), and the addition of the HUS data did not improve prediction. NDI was absent in 30% and 28% of the infants with grade IV intracranial hemorrhage or periventricular leukomalacia, respectively, but was present in 39% of the infants with a normal HUS result.

CONCLUSIONS

Clinical models were better than HUS models in predicting neurodevelopment.

Injury and recovery in the developing brain: evidence from functional MRI studies of prematurely born children

Functional MRI (fMRI) might provide important insights into emerging data that suggest that recovery from injury can occur in the brains of children born prematurely. Strategies employing auditory stimulation demonstrate blood-oxygen-level-dependent (BOLD) activation in preterm infants as young as 33 weeks' gestational age, and reliable BOLD signal in response to visual stimulation occurs at term-equivalent age. Strategies based on fMRI are particularly suited to the study of language and memory, and emerging data are likely to provide insights into perplexing reports that have demonstrated improving cognitive scores but persistent volumetric and microstructural changes in frontotemporal language systems in the prematurely born. Even when sex, gestational age and early medical and environmental interventions are taken into account, fMRI data from several investigators suggest the engagement of alternative neural networks for language and memory in the developing preterm brain.

Using cerebral ultrasound effectively in the newborn infant

Cranial ultrasound is the most available and easily repeatable technique for imaging the neonatal brain. Its quality and diagnostic accuracy depend on various factors; the suitability of the ultrasound machine for neonatal cranial work, the use of optimal settings and probes, appropriate scanning protocols, the use of a variety of acoustic windows and, not least, the scanning experience of the examiner. Knowledge of normal anatomy and the echogenicities of different tissues in normal and pathological situations as well as familiarity with the physiological and pathological processes likely to be encountered is vital. This paper assesses the value and appropriate use, safety and diagnostic accuracy of modern, high-quality ultrasound in evaluating the brain of the preterm and term born infant. Issues of concern regarding teaching, supervision and experience of the examiner are also addressed.

Increased Plasma Concentrations of Activin A Predict Intraventricular Hemorrhage in Preterm Newborns

Background: Intraventricular hemorrhage (IVH) is a major cause of neurologic disabilities in preterm newborns. We evaluated the use of plasma activin A concentrations to predict the development of perinatal IVH.

Methods: We measured nucleated erythrocyte (NRBC) counts, plasma activin A, hypoxanthine (Hyp), and xanthine (Xan) in arterial blood samples obtained from 53 preterm infants during the first hour after birth. Cerebral ultrasound was performed within 48 h of birth and repeated at 5- or 6-day intervals until the age of 4 weeks.

Results: Grade I or II IVH was detected during the first 10 days of life in 11 of 53 patients (21%). Activin A, Hyp, and Xan concentrations and NRBC counts were higher in preterm newborns who subsequently developed IVH than in those who did not (P &lt;0.0001, except P = 0.019 for Xan). Neonatal activin A was correlated (P &lt;0.0001) with Hyp (r = 0.95), Xan (r = 0.90), and NRBC count (r = 0.90) in newborns without later IVH and in those who developed IVH (Hyp, r = 0.89, P = 0.0002; Xan, r = 0.95, P &lt;0.0001; NRBC count, r = 0.90, P = 0.0002). At a cutoff of 0.8 μg/L activin A, the sensitivity and specificity were 100% [11 of 11; 95% confidence interval (CI), 71%–100%] and 93% (39 of 42; 95% CI, 81%–98%), and positive and negative predictive values were 79% (95% CI, 61%–100%) and 0% (95% CI, 0%–2%), respectively. The area under the ROC curve was 0.98.

Conclusions: Activin A concentrations at birth are increased in preterm newborns who later develop IVH and may be useful for early identification of infants with hypoxic-ischemic brain insults who are at high risk for IVH.

Transient periventricular echodensities in preterms and neurodevelopmental outcome

Little is known about the clinical evolution and neurologic sequelae of transient periventricular echodensities in the neonatal period. The aim of our study was to assess the neurodevelopmental outcome in preterm infants with transient periventricular echodensities. Cerebral ultrasonography was performed within the first 72 hours of life on all preterms with a < or = 37 weeks' gestational age who were admitted consecutively to the Neonatal Intensive Care Unit of the University of Parma from January 2001 to December 2002. Cerebral ultrasonography was performed at least twice within the 14th postnatal day and was repeated weekly until 40 weeks' postconceptional age. Transient aspecific echodensities were defined as areas in the periventricular region brighter than the choroid plexus persisting less than 14 days. One hundred sixty-four preterm infants were selected and divided into three groups: (1) 78 preterm infants without ultrasound abnormalities, (2) 50 preterm infants with transient periventricular echodensities, and (3) 36 preterm infants with persistent echodensities. Developmental outcome was assessed at 44 weeks' postconceptional age, after 1 month from the discharge and at the corrected ages of 3, 6, 9, and 12 months using the Griffiths Mental Developmental Scale. Group 1 and 2 infants showed normal neurodevelopment in 88.5% and 94% of cases, respectively, whereas the preterm infants belonging to group 3 had a favorable outcome in 22.2% (P < .001) of cases only. In conclusion, our study demonstrates how infants with transient echodensities show a neurodevelopmental outcome that is entirely identical to infants with a steadily negative ultrasound finding.

Morphine, hypotension, and adverse outcomes among preterm neonates: who's to blame? Secondary results from the NEOPAIN trial

OBJECTIVES

Hypotension occurs commonly among preterm neonates, but its cause and consequences remain unclear. Secondary data analyses from the NEOPAIN trial identified the clinical factors associated with hypotension and examined the contributions of morphine treatment or hypotension to severe intraventricular hemorrhage (IVH) (grades 3 and 4), any IVH (grades 1-4), or death.

METHODS

In the NEOPAIN trial, 898 ventilated neonates between 23 and 32 weeks of gestation were enrolled, with equal numbers randomized to receive masked morphine or placebo infusions. Additional doses of open-label morphine were administered as necessary by medical staff members. IVH was diagnosed with centralized readings of early and late cranial ultrasonograms. Hypotension was assessed before study drug infusion, during the loading dose, and at 24 and 72 hours during study drug infusion. Logistic regression analyses with stepdown elimination identified the predictor factors associated with the hypotension, severe IVH, any IVH, or death outcomes at each time point.

RESULTS

Hypotension was associated with 23 to 26 weeks of gestation, morphine infusions, severity of illness, additional morphine doses, and prior hypotension. Severe IVH was associated with shorter gestation, higher Clinical Risk Index for Babies scores, no prenatal steroids, pulmonary hemorrhage, hypotension before the loading dose, and morphine doses before intubation and at 25 to 72 hours. Neonatal deaths were associated with 23 to 26 weeks of gestation, higher Clinical Risk Index for Babies scores, pulmonary hemorrhage, patent ductus arteriosus, thrombocytopenia, and hypotension before the loading dose. Morphine infusions were not a significant factor in logistic models for severe IVH, any IVH, or death.

CONCLUSIONS

Preemptive morphine infusions, additional morphine, and lower gestational age were associated with hypotension among preterm neonates. Severe IVH, any IVH, and death were associated with preexisting hypotension, but morphine therapy did not contribute to these outcomes. Morphine infusions, although they cause hypotension, can be used safely for most preterm neonates but should be used cautiously for 23- to 26-week neonates and those with preexisting hypotension.

Intraventricular hemorrhage in the premature neonate

Intraventricular hemorrhage in the premature neonate has been and continues to be a cause of morbidity and mortality in NICUs around the globe. Much information is available concerning the etiology and preventative and treatment strategies to reduce the incidence of IVH in this patient population. As neonatal caregivers are struggling to care for and protect infants who are surviving despite extreme prematurity, this survival is complicated by the infant's cerebral vasculature, which is very susceptible to hemorrhage; by respiratory problems that require the use of lifesaving, but potentially harmful, ventilation interventions; and by the infant's compromised ability to self-regulate vascular responses to stress. The preventative treatments being explored and proposed may come with debilitating and potentially lethal sequelae. Research continues, however. New recommendations are being proffered, and perhaps, in the near future, the incidence of IVH and its associated morbidity and mortality will decline dramatically.