Predictive value of neonatal brain MRI on the neurodevelopmental outcome of preterm infants by 5 years of age

aEEG in the first 3 days after extremely preterm delivery relates to neurodevelopmental outcomes

OBJECTIVES

Investigate relationships between aEEG in the first 72 h in extremely preterm infants with 1) infant, medical, and environmental factors, and 2) infant feeding and neurobehavioral outcomes at term and school-age.

METHODS

Sixty-four preterm infants (≤28 weeks gestation) were enrolled within the first 24-hours of life and had two-channel aEEG until 72 h of life. Standardized neurobehavioral and feeding assessments were conducted at term, and parent-reported outcomes were documented at 5-7 years.

RESULTS

Lower aEEG Burdjalov scores (adjusted for gestational age) were related to vaginal delivery (p = 0.04), cerebral injury (p = 0.01), Black race (p < 0.01) and having unmarried parents (p = 0.02). Lower Burdjalov scores related to less NICU Network Neurobehavioral Scale arousal (p = 0.002) at term and poorer BRIEF global executive function (p = 0.004), inhibition (p = 0.007), working memory (p = 0.02), material organization (p = 0.0008), metacognition (p = 0.01), and behavioral regulation (p = 0.02) at 5-7 years. We did not observe relationships of early aEEG to feeding outcomes or sensory processing measures.

CONCLUSION

Early aEEG within the first 72 h of life was related to medical and sociodemographic factors as well as cognitive outcome at 5-7 years.

Major brain injuries at term continue to influence DTI parameters in adolescents born very preterm: a 13-year follow-up study

BACKGROUND

Major brain injuries in structural brain magnetic resonance imaging (MRI) at term affect concurrent diffusion tensor imaging (DTI) parameters in very preterm infants. White matter is known to gradually maturate along with increasing gestational age, which is characterized by increasing fractional anisotropy (FA) and decreasing mean diffusivity (MD).

PURPOSE

To study the difference between DTI parameters at term and 13 years in adolescents born very preterm with and without major pathologies in structural brain MRI at term.

MATERIAL AND METHODS

Adolescents born very preterm (gestational age <32 weeks and/or birth weight ≤1500 g) in 2004-2006 at Turku University Hospital, Finland were included. We evaluated FA and MD at term and 13 years in 18 regions of interest using the JHU-neonate-SS atlas to compare the differences in these parameters between adolescents with and without major injuries identified on MRI at term.

RESULTS

A total of 24 adolescents underwent brain MRI including DTI both at term and 13 years. Adolescents with major brain injury pathologies (n = 6) in structural MRI at term had decreased FA in the left corpus callosum and right cingulate gyrus part, and increased MD in the left corpus callosum, right anterior limb of internal capsule, and right posterior limb of the internal capsule at 13 years, in comparison with adolescents without major brain injuries (n = 18) in structural MRI at term.

CONCLUSION

Our findings suggest that major brain injuries identified on structural MRI at term affect brain maturation, with adverse effects in FA and MD still during adolescence.

Association of aEEG and brain injury severity on MRI at term-equivalent age in preterm infants

AIM

Measures to detect and monitor brain injury in preterm infants are amplitude-integrated electroencephalography (aEEG) and magnetic resonance imaging (MRI). To investigate the association between aEEG and MRI in a large cohort of preterm infants. Five hundred and twenty-three preterm infants were included in the study.

METHODS

AEEG was interpreted for the total maturation score (TMS) according to Burdjalov. Cerebral MRI was evaluated using a validated scoring system by Kidokoro.

RESULTS

One hundred and forty-six infants (27.9%) showed some form of brain injury, with 111 infants (21.2%) showing mild injury and 35 (6.7%) showing severe injury. TMS were significantly higher in infants without injury compared to severe injury. When comparing infants with isolated intraventricular haemorrhage  to infants without brain injury, TMS were significantly lower.

CONCLUSION

Prediction of adverse outcome is an important aspect of neonatal care. The combination of diagnostic measures evaluating brain injury might enhance our abilities in neonatal care to provide accurate information about later outcome. Early aEEG is predictive for the severity of brain injury detected by MRI at term-equivalent age. Whether aEEG is also predictive for neurodevelopmental outcome needs to be further investigated in relation to the various patterns of preterm brain injury.

Brain MRI findings and their association with visual impairment in young adolescents born very preterm

PURPOSE

Very preterm birth increases risk for neonatal white matter injury, but there is limited data on to what extent this persists into adolescence and how this relates to ophthalmological outcomes. The aim of this study was to assess brain MRI findings in 12-year-old children born very preterm compared to controls and their association with concurrent ophthalmological outcomes.

METHODS

We included 47 children born very preterm and 22 full-term controls (gestational age <32 and >37 weeks, respectively). Brain MRI findings were studied in association with concurrent ophthalmological outcomes at 12-year follow-up.

RESULTS

Evans index (0.27 vs 0.25, p<0.001) and a proposed "posterior ventricle index" (0.47 vs 0.45, p=0.018) were increased in children born very preterm. Higher gestational age associated with larger corpus callosum area (β=10.7, 95%CI 0.59-20.8). Focal white matter lesions were observed in 15 (32%) of very preterm children and in 1 (5%) of full-term controls. Increased posterior ventricle index increased risk for visual acuity ≤1.0 (OR=1.07×1011, 95%CI=7.78-1.48×1021) and contrast sensitivity <0.5 (OR=2.6×1027, 95%CI=1.9×108-3.5×1046). Decreased peritrigonal white matter thickness associated with impaired visual acuity (β=0.04, 95%CI 0.002-0.07).

CONCLUSION

More white matter lesions and evidence of lower white matter volume were found in children born very preterm compared with full-term controls at 12-year follow-up. The association between larger posterior ventricle index and reduced visual acuity and contrast sensitivity suggests disturbances of the posterior visual pathway due to diffuse white matter lesions.

Pre-notifications increase retention in a 17-year follow-up of adolescents born very preterm

OBJECTIVE

Retention is essential in follow-up studies to reduce missing data, which can cause bias and limit the generalizability of the results. We investigated whether pre-notification letters would increase the response rates of approval forms and questionnaires and reduce the need for post-notifications in a prospective follow-up study of 17-year-old adolescents.

STUDY DESIGN

and settings This long-term follow-up study included 269 adolescents were randomized (1:1) into a pre-notification group (n = 132) and a no pre-notification group (n = 137). The pre-notification letter was sent prior to the approval form and questionnaires. The outcome measures were the response rates to the approval forms and questionnaires and the rate of post-notifications required.

RESULTS

The adolescents who received the pre-notifications were more likely to return approval forms (n = 88/132, 67%) than the adolescents who did not receive the pre-notifications (n = 79/137, 58%) (OR 1.5, 95% CI 0.9-2.4). The rates of returned questionnaires were higher in the pre-notification group (n = 82/88, 93%) than in the no pre-notification group (n = 68/79, 86%) (OR 2.2, 95% CI 0.8-6.3). The adolescents who did not receive the pre-notifications were more likely to need the post-notifications than the adolescents who received the pre-notifications (OR 3.0, 95% CI 1.4 to 6.5).

CONCLUSIONS

Pre-notifications decreased the need for post-notifications and may increase retention in 17-year-old adolescents. Based on our findings, pre-notification letters are recommended in future follow-up studies in adolescents.

TRIAL REGISTRATION

The Ethics Review Committee of the Hospital District of South-West Finland approved the 17-year PIPARI Study protocol in January 2018 (23.1.2018; 2/180/2012). The study has been registered to the SWAT repository as SWAT 179. Filetoupload,1457904,en.pdf (qub.ac.uk).

Five-to-Fifteen-Parental Perception of Developmental Profile from Age 5 to 8 Years in Children Born Very Preterm

Children born very preterm have increased risk of developmental difficulties. We examined the parental perception of developmental profile of children born very preterm at 5 and 8 years by using the parental questionnaire Five-to-Fifteen (FTF) compared to full-term controls. We also studied the correlation between these age points. The study included 168 and 164 children born very preterm (gestational age < 32 weeks and/or birth weight ≤ 1500 g) and 151 and 131 full-term controls. The rate ratios (RR) were adjusted for sex and the father's educational level. At 5 and 8 years, children born very preterm were more likely to have higher scores (more difficulties) compared to controls in motor skills (RR = 2.3, CI 95% = 1.8-3.0 at 5 years and RR = 2.2, CI 95% = 1.7-2.9 at 8 years), executive function (1.7, 1.3-2.2 and 1.5, 1.2-2.0), perception (1.9, 1.4-2.5 and 1.9, 1.5-2.5), language (1.5, 1.1-1.9 and 2.2, 1.7-2.9), and social skills (1.4, 1.1-1.8 and 2.1, 1.6-2.7), and at 8 years in learning (1.9, 1.4-2.6) and memory (1.5, 1.2-2.0). There were moderate-to-strong correlations (r = 0.56-0.76, p < 0.001) in all domains between 5 and 8 years in children born very preterm. Our findings suggest that FTF might help to earlier identify children at the greatest risk of incurring developmental difficulties persisting to school-age.

Maternal smoking during pregnancy negatively affects brain volumes proportional to intracranial volume in adolescents born very preterm

Background

Maternal smoking during pregnancy has been shown to associate with smaller frontal lobe and cerebellar volumes in brain magnetic resonance imaging (MRI) at term age in very preterm infants. The aim of this study was to examine the effect of maternal smoking during pregnancy on volumetric brain MRI findings at 13 years. We hypothesized that adverse effects of smoking during pregnancy on brain volumes are still seen during adolescence.

Methods

Included adolescents were born very preterm (gestational age < 32 weeks and/or birth weight ≤ 1,500 g) between April 2004 and December 2006 at the Turku University Hospital, Finland. Information on maternal smoking status (yes or no) during pregnancy was collected from medical records and maternal questionnaires before discharge. Adolescents underwent volumetric brain MRI at 13 years of age. Image post-processing was performed with FreeSurfer. Regional volumes, cortical thickness, surface area, and curvature were computed from 33 cortical regions of interest (ROIs). Additionally, volumes were calculated for 18 subcortical regions, as well as for white matter, gray matter, and intracranial volume. We normalized quantified absolute volumes for head size by dividing volumes with corresponding intracranial volumes. false discovery rate (FDR) correction for multiple comparisons across regions was used.

Results

A total of 9/44 (21%) adolescents had been exposed to maternal smoking during pregnancy. No statistically significant differences in absolute volumes were observed between the groups (p > 0.05). Regarding volumes proportional to intracranial volume, the adolescents in the exposed group exhibited smaller gray matter volumes in the inferotemporal (FDR corrected p = 0.022) and parahippocampal (p = 0.018) regions compared to the unexposed group. The surface area in the exposed group was also smaller in the parahippocampal (p = 0.046) and postcentral (p = 0.046) regions compared to the unexposed group. No statistically significant differences after correction for multiple comparisons were found for either curvature or cortical thickness between the groups.

Conclusion

Maternal smoking exposure during pregnancy may have long-term effects on brain volumes up to 13 years in adolescents born very preterm. Our findings emphasize the importance of smoking-free pregnancy.

Peripapillary retinal nerve fibre layer thickness and macular ganglion cell layer volume in association with motor and cognitive outcomes in 11-year-old children born very preterm

PURPOSE

The purpose of the study was to study the association between retinal parameters and motor and cognitive outcomes in children born very preterm.

METHODS

This study is part of a prospective cohort study of very preterm infants (birth weight ≤ 1500 grams/gestational age < 32 weeks). At 11 years of age, the ophthalmological assessment included a retinal optical coherence tomography (OCT) examination of the peripapillary retinal nerve fibre layer (PRNFL) and the macular ganglion cell layer (GCL). The motor performance was assessed with the Movement Assessment Battery for Children-Second Edition (Movement ABC-2), and the cognitive outcome with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV).

RESULTS

A total of 141 children were included. The mean (SD) average PRNFL was 95 μm (10.2 μm). The mean (SD) macular GCL volume was 0.34 mm³ (0.03 mm³ ). Higher PRNFL thickness associated with higher percentiles for total scores in the motor assessment (b = 0.5, 95% CI 0.1-0.8, p = 0.01) and higher macular GCL volume with higher scores in the cognitive assessment (b = 1.4, 95% CI 0.5-2.3, p = 0.002), also when adjusted for gender, birth weight z-score (birth weight in relation to gestational age) and major brain pathology at term.

CONCLUSION

The associations between higher average PRNFL thickness and better motor performance as well as higher macular GCL volume and better cognitive performance refer to more generalized changes in the brain of 11-year-old children born very preterm. Retinal OCT examinations might provide a deeper insight than mere eyesight in long-term neurodevelopmental follow-up of children born very preterm.

Motor Performance in Association with Perceived Loneliness and Social Competence in 11-Year-Old Children Born Very Preterm

Background: Very preterm birth may affect motor performance and social competence up to adulthood. Our objective was to describe perceived loneliness and social competence in children born very preterm in relation to motor impairment. Methods: 165 children born very preterm (birth weight ≤ 1500 g and/or gestational age < 32 weeks) were assessed at 11 years of age. Cerebral palsy (CP) was diagnosed by 2 years of age. At 11 years of age, motor outcome was assessed using the Movement Assessment Battery for Children—Second edition (Movement ABC-2). Loneliness was evaluated by using the Peer Network and Dyadic Loneliness scale and social competence by using the Multisource Assessment of Children’s Social Competence Scale. Results: In total, 6 (4%) children had CP, 18 (11%) had Developmental Coordination Disorder (DCD) (Movement ABC-2 ≤ 5th percentiles), and 141 (85%) had typical motor development. There was no correlation between percentiles for total scores of the Movement ABC-2 and perceived loneliness or social competence when the children with motor impairment (CP or DCD) were excluded. Children with DCD reported less perceived loneliness, but more problems with social competence compared to children with CP. Conclusions: It is important to recognize children born very preterm with DCD to provide interventions and support services to prevent social exclusion.

Expert consensus on the clinical practice of neonatal brain magnetic resonance imaging

In recent years, magnetic resonance imaging (MRI) has been widely used in evaluating neonatal brain development, diagnosing neonatal brain injury, and predicting neurodevelopmental prognosis. Based on current research evidence and clinical experience in China and overseas, the Neonatologist Society of Chinese Medical Doctor Association has developed a consensus on the indications and standardized clinical process of neonatal brain MRI. The consensus has the following main points. (1) Brain MRI should be performed for neonates suspected of hypoxic-ischemic encephalopathy, intracranial infection, stroke and unexplained convulsions; brain MRI is not considered a routine in the management of preterm infants, but it should be performed for further evaluation when cranial ultrasound finds evidence of brain injury; as for extremely preterm or extremely low birth weight infants without abnormal ultrasound findings, it is recommended that they should undergo MRI examination at term equivalent age once. (2) Neonates should undergo MRI examination in a non-sedated state if possible. (3) During MRI examination, vital signs should be closely monitored to ensure safety; the necessity of MRI examination should be strictly evaluated for critically ill neonates, and magnetic resonance compatible incubator and ventilator can be used. (4) At present, 1.5 T or 3.0 T equipment can be used for neonatal brain MRI examination, and the special coil for the neonatal head should be used to improve signal-to-noise ratio; routine neonatal brain MRI sequences should at least include axial T1 weighted image (T1WI), axial T2 weighted imaging (T2WI), diffusion-weighted imaging, and sagittal T1WI or T2WI. (5) It is recommended to use a structured and graded reporting system, and reports by at least two reviewers and multi-center collaboration are recommended to increase the reliability of the report.

Associations between Language at 2 Years and Literacy Skills at 7 Years in Preterm Children Born at Very Early Gestational Age and/or with Very Low Birth Weight

Preterm children (born <37 gestational weeks) who are born at very early gestational age (<32 weeks, very preterm, VP) and/or with very low birth weight (≤1500 g, VLBW) are at increased risk for language and literacy deficits. The continuum between very early language development and literacy skills among these children is not clear. Our objective was to investigate the associations between language development at 2 years (corrected age) and literacy skills at 7 years in VP/VLBW children. Participants were 136 VP/VLBW children and 137 term controls (a 6-year regional population cohort, children living in Finnish-speaking families). At 2 years of corrected age, language (lexical development, utterance length) was assessed using the Finnish version of the MacArthur-Bates Communicative Development Inventory and the Expressive Language Scale from Bayley scales of Infant Development, second edition. At 7 years, children's literacy skills (pre-reading skills, reading, and writing) were evaluated. Statistically significant correlations were found in both groups between language development at 2 years and literacy skills at 7 years (r-values varied between 0.29 and 0.43, p < 0.01). In the VP/VLBW group, 33% to 74% of the children with early weak language development had weak literacy skills at 7 years relative to those with more advanced early language skills (11% to 44%, p < 0.001 to 0.047). Language development at 2 years explained 14% to 28% of the variance in literacy skills 5 years later. Language development at 2 years had fair predictive value for literacy skills at 7 years in the VP/VLBW group (area under the receiver operating characteristic (ROC) curve (AUC) values varied between 0.70 and 0.77, p < 0.001). Findings provide support for the continuum between very early language development and later language ability, in the domain of literacy skills in preterm children.

Comparative performance of head ultrasound and MRI in detecting preterm brain injury and predicting outcomes: A systematic review

AIM

To systematically review the literature to compare the performance of head ultrasound (HUS) and magnetic resonance imaging (MRI) in their ability to detect brain injury and their predictive value for neurodevelopmental outcomes.

METHODS

This was a systematic review based on literature search in three electronic databases (MEDLINE, EMBASE, Cochrane Library) and additional sources for studies on routine brain injury screening in preterm neonates published during 2000-May 2020. Studies were included if they reported on the comparative performance of HUS and MRI in detecting preterm brain injury and/or their predictive value for neurodevelopmental outcomes. Findings from the included studies underwent narrative synthesis.

RESULTS

Forty-six studies were included. In comparison with HUS, MRI detected more anomalies and provided more details on the severity and the extent of preterm brain injury, particularly for white matter injury and cerebellar haemorrhage. Neonatal neuroimaging predicted outcomes with high negative predictive value but relatively low positive predictive value. The prognostic value of neonatal neuroimaging varied according to several factors including modality and timing of imaging, and tools used for grading brain injury.

CONCLUSION

Compared with HUS, MRI offers a better characterisation of preterm brain injury and may enhance the ability to predict neurodevelopmental outcomes.

Using different definitions affected the reported prevalence of neurodevelopmental impairment in children born very preterm

AIM

We investigated the impact of varying definitions on the prevalence of neurodevelopmental impairment (NDI) in children born very preterm at 6.5 years of age.

METHODS

Cognitive development and neurosensory impairments were assessed in 91 children (40/51 girls/boys) born <32 gestational weeks, in 2004-2007 in Uppsala county, Sweden. The results were compared with data from a reference group of 67 children born full term. The prevalence of NDI in the present cohort was reported according to definitions used by seven contemporary studies of children born very or extremely preterm.

RESULTS

The prevalence of severe NDI varied from 2% to 23% depending on the definition used. The prevalence of cognitive impairment varied from 2% (-3 SD according to test norms) to 16% (-2 SD according to control group), the prevalence of cerebral palsy from 0% (severe) to 9% (any) and the prevalence of severe visual impairment from 0% (blindness) to 1% (visual acuity < 0.3). There were no children with severe hearing impairment.

CONCLUSION

A high variability in definitions affects the reporting of the prevalence of NDI in long-term follow-up studies of very or extremely preterm born children. There is a need for a better consensus to enable comparisons across studies.

The efficacy of routine brain MRI for term neonates admitted to neonatal intensive care unit

OBJECTIVE

The efficacy of routine brain MRI for term infants admitted to a neonatal intensive care unit (NICU) has not been well studied. This study aimed to investigate the types and frequencies of abnormal findings on routine brain MRI and the predictors of abnormality for term infants in an NICU setting.

METHODS

We examined the results of routine brain MRI of 239 term infants who were hospitalized in the NICU. Data on the perinatal factors were also collected, and the association with MRI abnormalities was assessed.

RESULTS

Of the 239 MRI scans, we found abnormal findings in 52 (21.8%) patients. Intracranial hemorrhage accounted for 74% of the abnormal findings, including subdural, intraparenchymal, cerebellar, and subependymal hemorrhages. Twenty-six percent of these were ischemic lesions, including cerebral infarction, white matter abnormal intensities, and cystic periventricular leukomalacia (PVL). Five (2.1%) MRI scans required detailed examination or were known to be associated with a poor neurological prognosis. No patient needed treatment for the findings. An Apgar score ≤7 points at 5 min was identified as a perinatal factor significantly associated with abnormal MRI findings (adjusted OR = 3.034, 95% CI: 1.107-8.315, p = .031).

CONCLUSION

The efficacy of routine brain MRI for term infants admitted to the NICU was limited. Routine brain MRI is not recommended for this population.

Neurodevelopmental outcome of preterm twins at 5 years of age

BACKGROUND

Twins are considered to be at an increased risk for perinatal mortality and morbidities, but it is unclear whether preterm twins are at an increased risk for poor developmental outcomes when compared to preterm singletons. Our aim was to compare the neurodevelopmental outcome of preterm twins vs singletons at 5 years of age.

METHODS

Very low birth weight and very low gestational age infants (twins n = 66, singletons n = 157) were recruited as a part of the PIPARI project in the Turku University Hospital, covering a regional population. Cognitive development, neuropsychological performance, and neurodevelopmental impairments (including cerebral palsy, hearing deficit, visual impairment, and intellectual disability) were evaluated at 5 years of age.

RESULTS

Twins and singletons had otherwise similar perinatal background factors, except for the higher proportion of preterm rupture of membranes in singletons. Twins had cognitive and neuropsychological outcomes that were otherwise comparable with singletons, but they had a slightly lower verbal intelligence quotient (estimate -5.81, 95% CI -11.14 to -0.48, p = 0.03). Being a twin was not a risk for neurodevelopmental impairments.

CONCLUSIONS

Our study shows that, contrary to a common hypothesis, the overall neurodevelopment of very preterm twins does not significantly differ from that of preterm singletons.

Preterm children's developmental coordination disorder, cognition and quality of life: a prospective cohort study

OBJECTIVE

To evaluate the rate of developmental coordination disorder (DCD) and its correlation to cognition and self-experienced health-related quality of life (HRQoL) in children born very preterm.

DESIGN

Prospective follow-up study.

SETTING

Regional population of children born very preterm in Turku University Hospital, Finland, in 2001-2006.

PATIENTS

A total of 170 children born very preterm were followed up until 11 years of age.

MAIN OUTCOME MEASURES

Motor and cognitive outcomes were evaluated using the Movement Assessment Battery for Children - Second Edition (Movement ABC-2) and the Wechsler Intelligence Scale for Children - Fourth Edition, respectively, and HRQoL using the 17-Dimensional Illustrated Questionnaire (17D). The Touwen neurological examination was performed to exclude other neurological conditions affecting the motor outcome.

RESULTS

Eighteen children born very preterm (17 boys) (11.3%) had DCD, defined as Movement ABC-2 total test score ≤5th percentile. A positive correlation between motor and cognitive outcome (r=0.22, p=0.006) was found. Children born very preterm with DCD had lower cognitive scores than those without DCD (Full-Scale IQ mean 76.8 vs 91.6, p=0.001). Moreover, children born very preterm with DCD reported lower HRQoL than children born very preterm without motor impairment (17D mean 0.93 vs 0.96, p=0.03). However, HRQoL was higher in this group of children born very preterm compared with population-based normative test results (p<0.001).

CONCLUSIONS

DCD was still common at 11 years of age in children born very preterm in 2000s. DCD associated with adverse cognitive development and lower self-experienced HRQoL. However, this group of children born very preterm reported better HRQoL in comparison with Finnish norms.

Structural neuroimaging

Characterizing the neuroanatomical correlates of brain development is essential in understanding brain-behavior relationships and neurodevelopmental disorders. Advances in brain MRI acquisition protocols and image processing techniques have made it possible to detect and track with great precision anatomical brain development and pediatric neurologic disorders. In this chapter, we provide a brief overview of the modern neuroimaging techniques for pediatric brain development and review key normal brain development studies. Characteristic disorders affecting neurodevelopment in childhood, such as prematurity, attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), epilepsy, and brain cancer, and key neuroanatomical findings are described and then reviewed. Large datasets of typically developing children and children with various neurodevelopmental conditions are now being acquired to help provide the biomarkers of such impairments. While there are still several challenges in imaging brain structures specific to the pediatric populations, such as subject cooperation and tissues contrast variability, considerable imaging research is now being devoted to solving these problems and improving pediatric data analysis.

Neuroimaging for Neurodevelopmental Prognostication in High-Risk Neonates

Predicting neurodevelopmental outcomes in high-risk neonates remains challenging despite advances in neonatal care. Early and accurate characterization of infants at risk for neurodevelopmental delays is necessary to best identify those who may benefit from existing early interventions and novel therapies that become available. Although neuroimaging is a promising biomarker in the prediction of neurodevelopmental outcomes in high-risk infants, it requires additional resources and expertise. Despite many advances in neonatal neuroimaging, there remain limitations in relating early neuroimaging findings with long-term outcomes; further studies are necessary to determine the optimal protocols to best identify high-risk patients and improve neurodevelopmental outcome prediction.

Factors affecting the cognitive profile of 11-year-old children born very preterm

BackgroundPreterm birth is a risk for cognitive development. This study assessed the cognitive profile of children born very preterm at the age of 11 years as well as the associated risk factors.MethodsA total of 128 children born very preterm were included. Magnetic resonance imaging was performed at term age. Cognitive development was assessed using the full-scale intelligence quotient (IQ) and four domains of the Wechsler Intelligence Scale for Children, fourth edition (WISC-IV), Finnish translation. The results were compared with test norms.ResultsMost study children performed at average (51%) or low average (21%) levels in the full-scale IQ assessment. The correlation between 5- and 11-year full-scale IQ was 0.73 (P<0.001). Compared with the normative data, children born very preterm performed poorer in all domains of the cognitive profile. The only significant risk factor for poor general cognition was major brain pathology. When considering all four domains of WISC-IV, low paternal education, male gender, and low birth weight z score were also found to be significant risk factors.ConclusionsLess than one-third of the children born very preterm performed below the low average cognitive level at 11 years of age. Specific neonatal and sociodemographic risk factors were identified as affecting the cognitive profile.

Challenges in neurologic prognostication after neonatal brain injury

Parents often ask neonatologists and neurologists to determine neurologic prognosis in the preterm and term infant after neonatal brain injury. Prognostication in these populations remains rather full of uncertainties. Knowledge of available diagnostic tests and their limitations allows the clinician to synthesize the most likely outcomes after neurologic injury. In this review, we describe the diagnostic tools available to the clinician, active areas of research, and challenges in neurologic prognostication of the neonate.

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.

The motor profile of preterm infants at 11 y of age

BACKGROUND

Preterm infants are at a higher risk for poor motor outcome than term infants. This study aimed to describe the long-term motor profile in very preterm born children.

METHODS

A total of 98 very preterm infants were included. Volumetric brain magnetic resonance imaging (MRI) was performed at term age, and the Movement Assessment Battery for Children-Second Edition (The Movement ABC-2) was employed at 11 y of age. The diagnosis of Developmental Coordination Disorder (DCD) was determined at 11 y of age according to the International Classification of Diseases.

RESULTS

Eighty-two of 98 (84%) very preterm infants had normal motor development at 11 y of age. In these children, the mean percentile for the total test score in the Movement ABC-2 examinations was 42 (SD 20). Eight (8%) children had DCD. The mean percentile in these children was 4 (SD 2). Eight (8%) children had CP. Their mean percentile was 6 (SD 14). Decreased volumes in all brain regions associated with lower Movement ABC-2 total scores.

CONCLUSION

The majority of the very preterm infants had normal motor development at 11 y of age. Volumetric brain MRI at term age provides a potential tool to identify risk groups for later neuromotor impairment.

Prediction of neuromotor outcome in infants born preterm at 11 years of age using volumetric neonatal magnetic resonance imaging and neurological examinations

AIM

To study the prognostic value of volumetric brain magnetic resonance imaging (MRI) at term equivalent age (TEA) and neurological examinations at TEA and at 2 years of corrected age for long-term neuromotor outcome in infants born very preterm.

METHOD

A total of 98 infants born very preterm were included. Structural and volumetric brain MRI and the Dubowitz neurologic examination were done at TEA. The Hammersmith Infant Neurological Examination (HINE) was performed at 2 years of corrected age. The Touwen examination was used for the assessment of minor neurological dysfunction (MND) at the age of 11 years.

RESULTS

Of all children (median birthweight 1083g [quartiles 820, 1300]; gestational age 28 5/7wks [26 4/7, 30 2/7]), 41 had simple MND, 11 had complex MND (cMND), and eight had cerebral palsy (CP). The negative and positive predictive value of structural brain MRI for cMND or CP was 88% and 50% respectively. Reduced volumes of total brain tissue, frontal lobes, basal ganglia and thalami, and cerebellum associated with cMND or CP. The results of the Dubowitz neurologic examination and the HINE correlated with the Touwen examination.

INTERPRETATION

Structural and volumetric MRI at TEA and structured neurological examinations predict long-term neuromotor outcome in infants born preterm.

Abnormal Ventricular Development in Preterm Neonates with Visually Normal MRIs

Children born preterm are at risk for a wide range of neurocognitive and neurobehavioral disorders. Some of these may stem from early brain abnormalities at the neonatal age. Hence, a precise characterization of neonatal neuroanatomy may help inform treatment strategies. In particular, the ventricles are often enlarged in neurocognitive disorders, due to atrophy of surrounding tissues. Here we present a new pipeline for the detection of morphological and relative pose differences in the ventricles of premature neonates compared to controls. To this end, we use a new hyperbolic Ricci flow based mapping of the ventricular surfaces of each subjects to the Poincaré disk. Resulting surfaces are then registered to a template, and a between group comparison is performed using mulitvariate tensor-based morphometry. We also statistically compare the relative pose of the ventricles within the brain between the two groups, by performing a Procrustes alignment between each subject's ventricles and an average shape. For both types of analyses, differences were found in the left ventricles between the two groups.

Semi-quantitative assessment of brain maturation by conventional magnetic resonance imaging in neonates with clinically mild hypoxic-ischemic encephalopathy

Background:

Mild hypoxic-ischemic encephalopathy (HIE) injury is becoming the major type in neonatal brain diseases. The aim of this study was to assess brain maturation in mild HIE neonatal brains using total maturation score (TMS) based on conventional magnetic resonance imaging (MRI).

Methods:

Totally, 45 neonates with clinically mild HIE and 45 matched control neonates were enrolled. Gestated age, birth weight, age after birth and postmenstrual age at magnetic resonance (MR) scan were homogenous in the two groups. According to MR findings, mild HIE neonates were divided into three subgroups: Pattern I, neonates with normal MR appearance; Pattern II, preterm neonates with abnormal MR appearance; Pattern III, full-term neonates with abnormal MR appearance. TMS and its parameters, progressive myelination (M), cortical infolding (C), involution of germinal matrix tissue (G), and glial cell migration bands (B), were employed to assess brain maturation and compare difference between HIE and control groups.

Results:

The mean of TMS was significantly lower in mild HIE group than it in the control group (mean ± standard deviation [SD] 11.62 ± 1.53 vs. 12.36 ± 1.26, P < 0.001). In four parameters of TMS scores, the M and C scores were significantly lower in mild HIE group. Of the three patterns of mild HIE, Pattern I (10 cases) showed no significant difference of TMS compared with control neonates, while Pattern II (22 cases), III (13 cases) all had significantly decreased TMS than control neonates (mean ± SD 10.56 ± 0.93 vs. 11.48 ± 0.55, P < 0.05; 12.59 ± 1.28 vs. 13.25 ± 1.29, P < 0.05). It was M, C, and GM scores that significantly decreased in Pattern II, while for Pattern III, only C score significantly decreased.

Conclusions:

The TMS system, based on conventional MRI, is an effective method to detect delayed brain maturation in clinically mild HIE. The conventional MRI can reveal the different retardations in subtle structures and development processes among the different patterns of mild HIE.

Preterm Birth and Poor Fetal Growth as Risk Factors of Attention-Deficit/ Hyperactivity Disorder

BACKGROUND

Previous studies have shown an association between prematurity and attention- abstract deficit/hyperactivity disorder (ADHD). Results concerning late preterm infants are controversial, and studies examining fetal growth represented by weight for gestational age are scarce. Our objective was to examine the association between gestational age by each week of fetal maturity, weight for gestational age, and ADHD.

METHODS

In this population-based study, 10 321 patients with ADHD, diagnosed according to the International Classification of Diseases and 38 355 controls individually matched for gender, date and place of birth, were identified from Finnish nationwide registers. Perinatal data were obtained from the Finnish Medical Birth Register. Conditional logistic regression was used to examine the association between gestational age, weight for gestational age, and ADHD after controlling for confounding factors.

RESULTS

The risk of ADHD increased by each declining week of gestation. The associations were robust after adjusting for confounders. An elevated risk also was seen among late preterm and early term infants. As for fetal growth, the odds ratio showed a U-shaped curve with an increased risk seen when the weight for gestational age was 1 SD below and 2 SD above the mean.

CONCLUSIONS

Our findings suggest that each gestational week has significance for child's subsequent neurodevelopment and risk for ADHD. We also showed that poor fetal growth increased the risk of ADHD. This highlights the importance of taking into account both prematurity and poor fetal growth when planning the timing of birth as well as later follow-up and support policies.

Choosing Wisely in Newborn Medicine: Five Opportunities to Increase Value

BACKGROUND

The use of unnecessary tests and treatments contributes to health care waste. The "Choosing Wisely" campaign charges medical societies with identifying such items. This report describes the identification of 5 tests and treatments in newborn medicine.

METHODS

A national survey identified candidate tests and treatments. An expert panel of 51 individuals representing 28 perinatal care organizations narrowed the list over 3 rounds of a modified Delphi process. In the final round, the panel was provided with Grading of Recommendation, Assessment, Development and Evaluation (GRADE) literature summaries of the top 12 tests and treatments.

RESULTS

A total of 1648 candidate tests and 1222 treatments were suggested by 1047 survey respondents. After 3 Delphi rounds, the expert panel achieved consensus on the following top 5 items: (1) avoid routine use of antireflux medications for treatment of symptomatic gastroesophageal reflux disease or for treatment of apnea and desaturation in preterm infants, (2) avoid routine continuation of antibiotic therapy beyond 48 hours for initially asymptomatic infants without evidence of bacterial infection, (3) avoid routine use of pneumograms for predischarge assessment of ongoing and/or prolonged apnea of prematurity, (4) avoid routine daily chest radiographs without an indication for intubated infants, and (5) avoid routine screening term-equivalent or discharge brain MRIs in preterm infants.

CONCLUSIONS

The Choosing Wisely Top Five for newborn medicine highlights tests and treatments that cannot be adequately justified on the basis of efficacy, safety, or cost. This list serves as a starting point for quality improvement efforts to optimize both clinical outcomes and resource utilization in newborn care.

Predictive validity of the Italian parental questionnaire for developmental evaluation at age 4 (QS4-G)

AIM

To examine whether the results at 4 years of age of the developmental questionnaire QS4-G can predict the outcome of cognitive, neuropsychological and academic abilities 4-6 years later. The QS4-G is a validated parental questionnaire designed for the screening and surveillance of the neuropsychological and behavioural developmental status of 4-year-olds (93 questions).

METHODS

Longitudinal prospective study on a subsample of the QS4-G validation original sample was conducted. According to previous results, the sample was divided into two groups: 'at risk' and 'not at risk'. Sensitivity, specificity, accuracy and likelihood ratios were assessed and referred to outcomes.

RESULTS

Thirty-five children were classified as 'not at risk' and 16 as 'at risk'. There were significant associations between past QS4-G score and cognitive, neuropsychological and academic abilities 4-6 years later. With the same cut-off identified at the first cross-sectional study, sensitivity and specificity for difficulties in cognitive development were 90% and 83% while in the neuropsychological abilities 62% and 90%, respectively. A lower predictive validity was found for difficulties in academic abilities (sensitivity 43%, specificity 86%). QS4-G specific area scores showed significant correlations with related academic tests at follow-up (rho range: 0.404-0.565, P < 0.005).

CONCLUSIONS

QS4-G shows good predictive validity for cognitive development and neuropsychological abilities. The risk of false negatives for academic abilities can be reduced by analysing the specific area results of QS4-G, which show good correlations with related tests at follow-up.

Predicting developmental outcomes in premature infants by term equivalent MRI: systematic review and meta-analysis

BACKGROUND

This study aims to determine the prognostic accuracy of term MRI in very preterm born (≤32 weeks) or low-birth-weight (≤1500 g) infants for long-term (>18 months) developmental outcomes.

METHODS

We performed a systematic review searching Central, Medline, Embase, and PsycInfo. Two independent reviewers performed study selection, data extraction, and quality assessment. We documented sensitivity and specificity for three different MRI findings (white matter abnormalities (WMA), brain abnormality (BA), and diffuse excessive high signal intensity (DEHSI)), related to developmental outcomes including cerebral palsy (CP), visual and/or hearing problems, motor, neurocognitive, and behavioral function. Using bivariate meta-analysis, we estimated pooled sensitivity and specificity and plotted summary receiver operating characteristic (sROC) curves for different cut-offs of MRI.

RESULTS

We included 20 papers published between 2000 and 2013. Quality of included studies varied. Pooled sensitivity and specificity values (95 % confidence interval (CI)) for prediction of CP combining the three different MRI findings (using normal/mild vs. moderate/severe cut-off) were 77 % (53 to 91 %) and 79 % (51 to 93 %), respectively. For prediction of motor function, the values were 72 % (52 to 86 %) and 62 % (29 to 87 %), respectively. Prognostic accuracy for visual and/or hearing problems, neurocognitive, and/or behavioral function was poor. sROC curves of the individual MRI findings showed that presence of WMA provided the best prognostic accuracy whereas DEHSI did not show any potential prognostic accuracy.

CONCLUSIONS

This study shows that presence of moderate/severe WMA on MRI around term equivalent age can predict CP and motor function in very preterm or low-birth-weight infants with moderate sensitivity and specificity. Its ability to predict other long-term outcomes such as neurocognitive and behavioral impairments is limited. Also, other white matter related tests as BA and DEHSI demonstrated limited prognostic value.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42013006362.

Neurological examination combined with brain MRI or cranial US improves prediction of neurological outcome in preterm infants

BACKGROUND

The predictive value of the combination of neurological examination and brain magnetic resonance imaging (MRI) or cranial ultrasound (cUS) in preterm infants is not known.

AIMS

To study the prognostic value of the combination of neurological examination and brain MRI at term equivalent age (TEA) or serial neonatal cUS in very preterm infants for neurosensory outcome at 2 years of corrected age.

STUDY DESIGN

A prospective follow-up study.

SUBJECTS

A total of 216 very preterm infants (birth weight 1132 g [SD 331 g]) born in Turku University Hospital, from 2001 to 2006, were included.

OUTCOME MEASURES

The Dubowitz neurologic examination and brain MRI were done at TEA, and serial cUS examinations were performed until TEA. The Hammersmith Infant Neurological Examination (HINE) and neurosensory impairments (NSI) were assessed at 2 years of corrected age.

RESULTS

Of all infants, 163 (76%) had one or more deviant neurological items at TEA, and 32 (15%) had the HINE total score below the 10th percentile at 2 years of corrected age. A total of 17 (8%) infants had NSI. Neurological examination at TEA improved the negative and positive predictive values of brain MRI for NSI from 99% to 100%, and from 28% to 35%, respectively, and the negative and positive predictive values of cUS from 97% to 100%, and from 61% to 79%, respectively.

CONCLUSIONS

The combination of the Dubowitz neurologic examination and the brain MRI at TEA or serial neonatal cUS provides a valuable clinical tool for predicting long-term neurosensory outcome in preterm infants.

The role of neuroimaging in predicting neurodevelopmental outcomes of preterm neonates

Magnetic resonance imaging (MRI) is a safe and high-resolution neuroimaging modality that is increasingly used in the neonatal population to assess brain injury and its consequences on brain development. It is superior to cranial ultrasound for the definition of patterns of both white and gray matter maturation and injury and therefore has the potential to provide prognostic information on the neurodevelopmental outcomes of the preterm population. Furthermore, the development of sophisticated MRI strategies, including diffusion tensor imaging, resting state functional connectivity, and magnetic resonance spectroscopy, may increase the prognostic value, helping to guide parental counseling and allocate early intervention services.

Imaging the premature brain: ultrasound or MRI?

Neuroimaging of preterm infants has become part of routine clinical care, but the question is often raised on how often cranial ultrasound should be done and whether every high risk preterm infant should at least have one MRI during the neonatal period. An increasing number of centres perform an MRI either at discharge or around term equivalent age, and a few centres have access to a magnet in or adjacent to the neonatal intensive care unit and are doing sequential MRIs. In this review, we try to discuss when best to perform these two neuroimaging techniques and the additional information each technique may provide.