Can 3-dimensional cranial ultrasound be used to successfully reconstruct a 2-dimensional image without compromising on image quality in a neonatal population?

BACKGROUND: Cranial ultrasound is frequently performed in neonatal intensive care units and acquiring 2-dimensional (D) images requires significant training. Three-D ultrasound images can be acquired semi-automatically. OBJECTIVE: This proof-of-concept study aimed to demonstrate that 3-D study image quality compares well with 2-D. If this is successful, 3-D images could be acquired in remote areas and read remotely by experts. MATERIALS AND METHODS: This was a prospective study of 20 neonates, who underwent both routine 2-D and 3-D cranial ultrasounds. Images were reconstructed into standard views extracted from the 3-D volume and evaluated by three radiologists blinded to the acquisition method. The radiologists assessed for the presence of anatomical landmarks and overall image quality. RESULTS: More anatomical structures were identified in the 3-D studies (P<0.01). There was a trend that 3-D ultrasound demonstrated better image quality in the coronal plane, and 2-D in the sagittal plane, only reaching statistical significance for two coronal views and two sagittal views. CONCLUSION: Overall, this study has demonstrated that 3-D cranial ultrasound performs similarly to 2-D and could be implemented into neonatal practice.

Expanding ACTA2 genotypes with corresponding phenotypes overlapping with smooth muscle dysfunction syndrome.

Pathogenic variants in ACTA2, encoding smooth muscle α-actin, predispose to thoracic aortic aneurysms and dissections. ACTA2 variants altering arginine 179 predispose to a more severe, multisystemic disease termed smooth muscle dysfunction syndrome (SMDS; OMIM 613834). Vascular complications of SMDS include patent ductus arteriosus (PDA) or aortopulmonary window, early-onset thoracic aortic disease (TAD), moyamoya-like cerebrovascular disease, and primary pulmonary hypertension. Patients also have dysfunction of other smooth muscle-dependent systems, including congenital mydriasis, hypotonic bladder, and gut hypoperistalsis. Here, we describe five patients with novel heterozygous ACTA2 missense variants, p.Arg179Gly, p.Met46Arg, p.Thr204Ile, p.Arg39Cys, and p.Ile66Asn, who have clinical complications that align or overlap with SMDS. Patients with the ACTA2 p.Arg179Gly and p.Thr204Ile variants display classic features of SMDS. The patient with the ACTA2 p.Met46Arg variant exhibits exclusively vascular complications of SMDS, including early-onset TAD, PDA, and moyamoya-like cerebrovascular disease. The patient with the ACTA2 p.Ile66Asn variant has an unusual vascular complication, a large fusiform internal carotid artery aneurysm. The patient with the ACTA2 p.Arg39Cys variant has pulmonary, gastrointestinal, and genitourinary complications of SMDS but no vascular manifestations. Identifying pathogenic ACTA2 variants associated with features of SMDS is critical for aggressive surveillance and management of vascular and nonvascular complications and delineating the molecular pathogenesis of SMDS.

Drainage, irrigation and fibrinolytic therapy (DRIFT) for posthaemorrhagic ventricular dilatation: 10-year follow-up of a randomised controlled trial.

BACKGROUND: Progressive ventricular dilatation after intraventricular haemorrhage (IVH) in preterm infants has a very high risk of severe disability and death. Drainage, irrigation and fibrinolytic therapy (DRIFT), in a randomised controlled trial (RCT), reduced severe cognitive impairment at 2 years. OBJECTIVE: To assess if the cognitive advantage of DRIFT seen at 2 years persisted until school age. PARTICIPANTS: The RCT conducted in four centres recruited 77 preterm infants with IVH and progressive ventricular enlargement over specified measurements. Follow-up was at 10 years of age. INTERVENTION: Intraventricular injection of a fibrinolytic followed by continuous lavage, until the drainage was clear, and standard care consisting of control of expansion by lumbar punctures and if expansion persisted via a ventricular access device. PRIMARY OUTCOME: Cognitive quotient (CQ), derived from the British Ability Scales and Bayley III Scales, and survival without severe cognitive disability. RESULTS: Of the 77 children randomised, 12 died, 2 could not be traced, 10 did not respond and 1 declined at 10-year follow-up. 28 in the DRIFT group and 24 in the standard treatment group were assessed by examiners blinded to the intervention. The mean CQ score was 69.3 (SD=30.1) in the DRIFT group and 53.7 (SD=35.7) in the standard treatment group (unadjusted p=0.1; adjusted p=0.01, after adjustment for the prespecified variables sex, birth weight and IVH grade). Survival without severe cognitive disability was 66% in the DRIFT group and 35% in the standard treatment group (unadjusted p=0.019; adjusted p=0.003). CONCLUSION: DRIFT is the first intervention for posthaemorrhagic ventricular dilatation to objectively demonstrate sustained cognitive improvement. TRIAL REGISTRATION NUMBER: ISRCTN80286058.

Serial C-Reactive Protein Measurements in Newborn Infants without Evidence of Early-Onset Infection.

BACKGROUND: C-reactive protein (CRP) is used to assist the diagnosis and monitoring of newborn infection. Little is known about CRP activity after birth in the absence of infection. OBJECTIVE: The aim of this work was to describe postnatal CRP responses in the first days of life in asymptomatic infants with a negative blood culture. METHODS: Data were collected from infants who had a blood culture taken at <72 h of age in a UK maternity hospital. All CRP values and their time from birth were recorded. Infants with signs of infection, positive blood culture, or major congenital anomalies were excluded. Infants were analysed by gestation (greater or less than 37 weeks). Normalised CRP curves were generated by linear interpolation and centile curves were derived. Comparisons of median CRP values between groups were made by Mann-Whitney U test at 24, 36, and 48 h. RESULTS: During the study period a total of 219 babies were screened. After exclusions, 73 infants (58 term, 15 preterm) were analysed. In asymptomatic term neonates the CRP (mg/L) peaked at 9.4 after 34.6 h. In preterm babies the CRP peak was 1.75 at 43 h. The median (IQR) values were higher in the term group at 24 and 36 h: 2.5 (1-10.5) versus 0 (0-2.2; p = 0.02) and 3 (0-8.6) versus 0 (0-2.8; p = 0.031). CONCLUSIONS: A CRP rise was demonstrated in term and preterm infants without evidence of infection. This rise was greatest in term infants. CRP values must be interpreted in the context of an infant's clinical condition and not used alone to guide clinical decision making.

Ten-year follow-up of a randomised trial of drainage, irrigation and fibrinolytic therapy (DRIFT) in infants with post-haemorrhagic ventricular dilatation.

BACKGROUND: The drainage, irrigation and fibrinolytic therapy (DRIFT) trial, conducted in 2003-6, showed a reduced rate of death or severe disability at 2 years in the DRIFT compared with the standard treatment group, among preterm infants with intraventricular haemorrhage (IVH) and post-haemorrhagic ventricular dilatation. OBJECTIVES: To compare cognitive function, visual and sensorimotor ability, emotional well-being, use of specialist health/rehabilitative and educational services, neuroimaging, and economic costs and benefits at school age. DESIGN: Ten-year follow-up of a randomised controlled trial. SETTING: Neonatal intensive care units (Bristol, Katowice, Glasgow and Bergen). PARTICIPANTS: Fifty-two of the original 77 infants randomised. INTERVENTIONS: DRIFT or standard therapy (cerebrospinal fluid tapping). MAIN OUTCOME MEASURES: Primary - cognitive disability. Secondary - vision; sensorimotor disability; emotional/behavioural function; education; neurosurgical sequelae on magnetic resonance imaging; preference-based measures of health-related quality of life; costs of neonatal treatment and of subsequent health care in childhood; health and social care costs and impact on family at age 10 years; and a decision analysis model to estimate the cost-effectiveness of DRIFT compared with standard treatment up to the age of 18 years. RESULTS: By 10 years of age, 12 children had died and 13 were either lost to follow-up or had declined to participate. A total of 52 children were assessed at 10 years of age (DRIFT, n = 28; standard treatment, n = 24). Imbalances in gender and birthweight favoured the standard treatment group. The unadjusted mean cognitive quotient (CQ) score was 69.3 points [standard deviation (SD) 30.1 points] in the DRIFT group compared with 53.7 points (SD 35.7 points) in the standard treatment group, a difference of 15.7 points, 95% confidence interval (CI) -2.9 to 34.2 points; p = 0.096. After adjusting for the prespecified covariates (gender, birthweight and grade of IVH), this evidence strengthened: children who received DRIFT had a CQ advantage of 23.5 points (p = 0.009). The binary outcome, alive without severe cognitive disability, gave strong evidence that DRIFT improved cognition [unadjusted odds ratio (OR) 3.6 (95% CI 1.2 to 11.0; p = 0.026) and adjusted OR 10.0 (95% CI 2.1 to 46.7; p = 0.004)]; the number needed to treat was three. No significant differences were found in any secondary outcomes. There was weak evidence that DRIFT reduced special school attendance (adjusted OR 0.27, 95% CI 0.07 to 1.05; p = 0.059). The neonatal stay (unadjusted mean difference £6556, 95% CI -£11,161 to £24,273) and subsequent hospital care (£3413, 95% CI -£12,408 to £19,234) costs were higher in the DRIFT arm, but the wide CIs included zero. The decision analysis model indicated that DRIFT has the potential to be cost-effective at 18 years of age. The incremental cost-effectiveness ratio (£15,621 per quality-adjusted life-year) was below the National Institute for Health and Care Excellence threshold. The cost-effectiveness results were sensitive to adjustment for birthweight and gender. LIMITATIONS: The main limitations are the sample size of the trial and that important characteristics were unbalanced at baseline and at the 10-year follow-up. Although the analyses conducted here were prespecified in the analysis plan, they had not been prespecified in the original trial registration. CONCLUSIONS: DRIFT improves cognitive function when taking into account birthweight, grade of IVH and gender. DRIFT is probably effective and, given the reduction in the need for special education, has the potential to be cost-effective as well. A future UK multicentre trial is required to assess efficacy and safety of DRIFT when delivered across multiple sites. TRIAL REGISTRATION: Current Controlled Trials ISRCTN80286058. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 4. See the NIHR Journals Library website for further project information. The DRIFT trial and 2-year follow-up was funded by Cerebra and the James and Grace Anderson Trust.

A Sterile Collection Bundle Intervention Reduces the Recovery of Bacteria from Neonatal Blood Culture.

BACKGROUND: In neonatal intensive care, coagulase-negative Staphylococcus species can be both blood culture contaminants and pathogens. False-positive cultures can result in clinical uncertainty and unnecessary antibiotic use. OBJECTIVE: This study sought to assess whether a sterile blood culture collection bundle would reduce the incidence of false-positive blood cultures in a regional neonatal intensive care unit. METHOD: Clinical data was collected from all infants who had blood cultures taken before and after the introduction of the sterile blood culture collection bundle intervention. This intervention required 2% chlorhexidine and full sterile precautions for blood culture collection. False-positive blood culture rates (presence of skin commensals and ≥3 clinical infection signs) were compared before and after the intervention. The number of days of unnecessary antibiotics associated with false-positive blood cultures was also analysed. RESULTS: In the pre-intervention group (PRE) 197 cultures were taken from 161 babies. In the post-intervention group (POST) 170 cultures from 133 babies were acquired. Baseline demographics were similar in both groups. The rate of false-positive cultures in the PRE group versus the POST group was 9/197 (4.6%) compared to 1/170 (0.6%) (p < 0.05). Unnecessary antibiotic exposure was reduced in the PRE group in comparison to the POST group (27 vs. 0 days, p < 0.01). CONCLUSIONS: Implementation of sterile blood culture collection intervention reduced the number of false-positive results. This has potential benefit in reducing unnecessary antibiotic use.

Cerebral White Matter Maturation Patterns in Preterm Infants: An MRI T2 Relaxation Anisotropy and Diffusion Tensor Imaging Study.

BACKGROUND AND PURPOSE: Preterm birth is associated with worse neurodevelopmental outcome, but brain maturation in preterm infants is poorly characterized with standard methods. We evaluated white matter (WM) of infant brains at term-equivalent age, as a function of gestational age at birth, using multimodal magnetic resonance imaging (MRI). METHODS: Infants born very preterm (<32 weeks gestation) and late preterm (33-36 weeks gestation) were scanned at 3 T at term-equivalent age using diffusion tensor imaging (DTI) and T2 relaxometry. MRI data were analyzed using tract-based spatial statistics, and anisotropy of T2 relaxation was also determined. Principal component analysis and linear discriminant analysis were applied to seek the variables best distinguishing very preterm and late preterm groups. RESULTS: Across widespread regions of WM, T2 is longer in very preterm infants than in late preterm ones. These effects are more prevalent in regions of WM that myelinate earlier and faster. Similar effects are obtained from DTI, showing that fractional anisotropy (FA) is lower and radial diffusivity higher in the very preterm group, with a bias toward earlier myelinating regions. Discriminant analysis shows high sensitivity and specificity of combined T2 relaxometry and DTI for the detection of a distinct WM development pathway in very preterm infants. T2 relaxation is anisotropic, depending on the angle between WM fiber and magnetic field, and this effect is modulated by FA. CONCLUSIONS: Combined T2 relaxometry and DTI characterizes specific patterns of retarded WM maturation, at term equivalent age, in infants born very preterm relative to late preterm.

Functional Laterality of Task-Evoked Activation in Sensorimotor Cortex of Preterm Infants: An Optimized 3 T fMRI Study Employing a Customized Neonatal Head Coil.

BACKGROUND: Functional magnetic resonance imaging (fMRI) in neonates has been introduced as a non-invasive method for studying sensorimotor processing in the developing brain. However, previous neonatal studies have delivered conflicting results regarding localization, lateralization, and directionality of blood oxygenation level dependent (BOLD) responses in sensorimotor cortex (SMC). Amongst the confounding factors in interpreting neonatal fMRI studies include the use of standard adult MR-coils providing insufficient signal to noise, and liberal statistical thresholds, compromising clinical interpretation at the single subject level. PATIENTS / METHODS: Here, we employed a custom-designed neonatal MR-coil adapted and optimized to the head size of a newborn in order to improve robustness, reliability and validity of neonatal sensorimotor fMRI. Thirteen preterm infants with a median gestational age of 26 weeks were scanned at term-corrected age using a prototype 8-channel neonatal head coil at 3T (Achieva, Philips, Best, NL). Sensorimotor stimulation was elicited by passive extension/flexion of the elbow at 1 Hz in a block design. Analysis of temporal signal to noise ratio (tSNR) was performed on the whole brain and the SMC, and was compared to data acquired with an 'adult' 8 channel head coil published previously. Task-evoked activation was determined by single-subject SPM8 analyses, thresholded at p < 0.05, whole-brain FWE-corrected. RESULTS: Using a custom-designed neonatal MR-coil, we found significant positive BOLD responses in contralateral SMC after unilateral passive sensorimotor stimulation in all neonates (analyses restricted to artifact-free data sets = 8/13). Improved imaging characteristics of the neonatal MR-coil were evidenced by additional phantom and in vivo tSNR measurements: phantom studies revealed a 240% global increase in tSNR; in vivo studies revealed a 73% global and a 55% local (SMC) increase in tSNR, as compared to the 'adult' MR-coil. CONCLUSIONS: Our findings strengthen the importance of using optimized coil settings for neonatal fMRI, yielding robust and reproducible SMC activation at the single subject level. We conclude that functional lateralization of SMC activation, as found in children and adults, is already present in the newborn period.

Protecting the premature brain: current evidence-based strategies for minimising perinatal brain injury in preterm infants.

Improving neurodevelopmental outcome for preterm infants is an important challenge for neonatal medicine. The disruption of normal brain growth and neurological development is a significant consequence of preterm birth and can result in physical and cognitive impairments. While advances in neonatal medicine have led to progressively better survival rates for preterm infants, there has only been a modest improvement in the proportion of surviving infants without neurological impairment, and no change in the proportion with severe disability. The overall number of children with neurodisability due to prematurity is increasing. Trials investigating novel therapies are underway and many have promising early results; however, in the interim, current treatments and management strategies that have proven benefit for neurodevelopment or reduction in neonatal brain injury are often underutilised. We collate the evidence for the efficacy of such interventions, recommended by guidelines or supported by large meta-analysis or randomised control trials. We address controversies that have hindered uptake and problems with translating research into practice. We then look to the future of preterm neuroprotective care.

High frequency functional brain networks in neonates revealed by rapid acquisition resting state fMRI.

Understanding how spatially remote brain regions interact to form functional brain networks, and how these develop during the neonatal period, provides fundamental insights into normal brain development, and how mechanisms of brain disorder and recovery may function in the immature brain. A key imaging tool in characterising functional brain networks is examination of T2*-weighted fMRI signal during rest (resting state fMRI, rs-fMRI). The majority of rs-fMRI studies have concentrated on slow signal fluctuations occurring at <0.1 Hz, even though neuronal rhythms, and haemodynamic responses to these fluctuate more rapidly, and there is emerging evidence for crucial information about functional brain connectivity occurring more rapidly than these limits. The characterisation of higher frequency components has been limited by the sampling frequency achievable with standard T2* echoplanar imaging (EPI) sequences. We describe patterns of neonatal functional brain network connectivity derived using accelerated T2*-weighted EPI MRI. We acquired whole brain rs-fMRI data, at subsecond sampling frequency, from preterm infants at term equivalent age and compared this to rs-fMRI data acquired with standard EPI acquisition protocol. We provide the first evidence that rapid rs-fMRI acquisition in neonates, and adoption of an extended frequency range for analysis, allows identification of a substantial proportion of signal power residing above 0.2 Hz. We thereby describe changes in brain connectivity associated with increasing maturity which are not evident using standard rs-fMRI protocols. Development of optimised neonatal fMRI protocols, including use of high speed acquisition sequences, is crucial for understanding the physiology and pathophysiology of the developing brain.

Managing children with raised intracranial pressure: part two (brain tumours and intracranial bleeds).

This article is the second of two examining the causes of increased intracranial pressure in children. Key features and management associated with brain tumours and intracranial bleeds are highlighted. The conditions are accompanied by illustrative case studies to give an idea of what children's nurses may encounter in a patient presenting with raised intracranial pressure. Part one, published in December 2013, focused on the signs and symptoms of raised intracranial pressure and meningitis.

Managing children with raised intracranial pressure: part one (introduction and meningitis).

Intracranial pathologies in children need urgent identification and management. This article is presented in two parts, with part one describing intracranial pressure and outlining the features and management of meningitis. Part two, to be published in February 2014, outlines the features and management of brain tumours and intracranial bleeds. Each condition is accompanied by an illustrative case study to give an idea of what nurses might encounter in a child presenting with raised intracranial pressure.

Recognition of face and non-face stimuli in autistic spectrum disorder.

The ability to remember faces is critical for the development of social competence. From childhood to adulthood, we acquire a high level of expertise in the recognition of facial images, and neural processes become dedicated to sustaining competence. Many people with autism spectrum disorder (ASD) have poor face recognition memory; changes in hairstyle or other non-facial features in an otherwise familiar person affect their recollection skills. The observation implies that they may not use the configuration of the inner face to achieve memory competence, but bolster performance in other ways. We aimed to test this hypothesis by comparing the performance of a group of high-functioning unmedicated adolescents with ASD and a matched control group on a "surprise" face recognition memory task. We compared their memory for unfamiliar faces with their memory for images of houses. To evaluate the role that is played by peripheral cues in assisting recognition memory, we cropped both sets of pictures, retaining only the most salient central features. ASD adolescents had poorer recognition memory for faces than typical controls, but their recognition memory for houses was unimpaired. Cropping images of faces did not disproportionately influence their recall accuracy, relative to controls. House recognition skills (cropped and uncropped) were similar in both groups. In the ASD group only, performance on both sets of task was closely correlated, implying that memory for faces and other complex pictorial stimuli is achieved by domain-general (non-dedicated) cognitive mechanisms. Adolescents with ASD apparently do not use domain-specialized processing of inner facial cues to support face recognition memory.

Specific neural correlates of successful learning and adaptation during social exchanges.

Cooperation and betrayal are universal features of social interactions, and knowing who to trust is vital in human society. Previous studies have identified brain regions engaged by decision making during social encounters, but the mechanisms supporting modification of future behaviour by utilizing social experience are not well characterized. Using functional magnetic resonance imaging (fMRI), we show that cooperation and betrayal during social exchanges elicit specific patterns of neural activity associated with future behaviour. Unanticipated cooperation leads to greater behavioural adaptation than unexpected betrayal, and is signalled by specific neural responses in the striatum and midbrain. Neural responses to betrayal and willingness to trust novel partners both decrease as the number of individuals encountered during repeated social encounters increases. We propose that, as social groups increase in size, uncooperative or untrustworthy behaviour becomes progressively less surprising, with cooperation becoming increasingly important as a stimulus for social learning. Effects on reputation of non-trusting decisions may also act to drive pro-social behaviour. Our findings characterize the dynamic neural processes underlying social adaptation, and suggest that the brain is optimized to cooperate with trustworthy partners, rather than avoiding those who might betray us.