Biomedical subjects

L Dubowitz

Publications and source records attributed to L Dubowitz.

At least 19 recordsLinked to original sources

PubMed2006

Sequential neurological examinations in infants with neonatal encephalopathy and low apgar scores: relationship with brain MRI.

OBJECTIVE: The aims of this study were to (a) describe the evolution of neurological signs after the neonatal period in infants with neonatal encephalopathy and abnormal outcome and (b) to establish the relationship between the evolution of neurological signs and patterns of lesions on brain MRI. PATIENTS: Fifteen children with low Apgar scores, abnormal neurological signs at the end of the neonatal period, and abnormal outcome were examined at 1 - 2 weeks, 5 - 7 weeks, and 6 months. All the infants had at least one MRI scan performed in the neonatal period. RESULTS: All infants had persistent abnormalities on all examinations performed but the severity of neurological impairment was variable and was related to the pattern of brain lesions. Infants with severe basal ganglia and white matter lesions showed abnormal axial and limb tone, movements, and visual function on all the examinations and none achieved independent sitting. In infants with moderate basal ganglia lesions and/or severe white matter changes, visual function and feeding improved by 5 - 7 weeks and were still normal at 6 months while limb tone, which was reduced in the first weeks, appeared to be normal at 5 - 6 weeks but was found to be increased at 6 months; all were able to sit unsupported at 2 years and most of them achieved the ability to walk with support. CONCLUSIONS: Our results suggest that the evolution of the neurological patterns after the neonatal period in infants with persisting neonatal abnormalities depends on their pattern of brain lesions.

Apgar Score↗

PubMed2006

Neurological examination at 6 to 9 months in infants with cystic periventricular leukomalacia.

The Hammersmith Infant Neurological Examination was performed in 24 infants with cystic periventricular leukomalacia whose gestational age ranged between 26-38 weeks. The infants were examined between 6 and 9.5 months corrected age. The aim of the study was to establish the different patterns of neurological abnormality as well as the optimality scores that predict the severity of motor sequelae at 2 years. Increased neck and trunk extensor tone, and a posture of flexed arms and extended legs between 6 and 9 months were always associated with the inability to sit unsupported at 2 years, whilst truncal hypotonia and extended arms and legs were associated with unsupported sitting but not walking. Optimality scores between 41 and 60 were generally associated with sitting but not walking at 2 years whilst scores below 40 were always associated with the inability to sit independently at 2 years. All infants who did not develop cerebral palsy at 2 years had scores > 60. Our results suggest that the pattern of findings on neurological examination performed between 6 and 9 months as well as the calculated optimality score helps to predict motor impairment in infants with PVL.

Female↗

PubMed2004

Can the Griffiths scales predict neuromotor and perceptual-motor impairment in term infants with neonatal encephalopathy?

AIMS: To examine the predictive value of early developmental testing for identifying neuromotor and perceptual-motor impairment at school age in children with neonatal encephalopathy (NE). METHODS: Eighty full term infants with NE were followed longitudinally. Where possible, children were tested on the Griffiths scales at 1 and 2 years and at 5-6 years, on the Touwen Examination, Movement ABC, and WPPSI. The relation between the Griffiths scores and later outcome measures was examined using correlation coefficients and sensitivity and specificity values. RESULTS: By 2 years, 25 children with cerebral palsy were too severely impaired to be formally assessed and remained so at 5-6 years. Abnormal Griffiths scores were obtained by 12% and 7% of the children at 1 and 2 years respectively. At 5-6 years, 33% had poor Movement ABC scores and 15% poor WPPSI scores. The highest correlation between Griffiths scores and the outcome measures was for the Movement ABC (0.72), although this accounted for only 50% of the variance. Sensitivity scores for the Movement ABC were below 70% but specificity was 100%. CONCLUSIONS: A poor score on the Griffiths scales at 1 and/or 2 years is a good predictor of impairment at school age. However, a normal score in the early years cannot preclude later neurological, perceptual-motor, or cognitive abnormalities.

Brain Diseases↗

PubMed2004

Visual function at school age in children with neonatal encephalopathy and low Apgar scores.

OBJECTIVE: To assess different aspects of visual function at school age in children who suffered from neonatal encephalopathy. METHOD: Thirty nine full term infants with neonatal encephalopathy, low Apgar scores, and early neonatal imaging were studied using a battery of tests assessing different aspects of visual function (crowding acuity, stereopsis, visual fields) at school age. The results were compared with brain magnetic resonance imaging (MRI) findings and, when possible, with the results of the assessment of visual function performed at 5 and 12 months, available in 24 of the 39 children examined at school age. RESULTS: Sixteen of the 39 children (41%) had abnormal results at school age in at least one of the visual tests used. Seven of these 16 were untestable on all tests. The remaining 23 children (59%) had normal results. CONCLUSIONS: The presence and severity of visual impairment was related to the severity of brain lesions. Moderate or severe basal ganglia lesions and severe white matter changes were always associated with abnormal visual function. Infants with normal MRI, minimal basal ganglia lesions, and minimal or moderate white matter involvement tended to have normal vision. It was also found that the assessment of visual function performed in the first year was a reliable indicator of visual function at school age. With two exceptions, the results on the 5 month visual assessment were predictive of visual outcome at school age. In the remaining two cases, a normal visual outcome at 5 years was associated with visual abnormalities at 5 months but these had already normalised by the age of 1 year.

Apgar Score↗

PubMed2003

General movements detect early signs of hemiplegia in term infants with neonatal cerebral infarction.

Background. Studies have reported that infants with hemiplegia of congenital origin may have a period between birth and up to 12 months when clinical signs of hemiplegia are not evident. The aim of this study was to establish whether the assessment of general movements (GMs) may help in the earlier detection of signs of hemiplegia. Subjects and Methods. Eleven infants with cerebral infarction on brain MRI, and eleven normal controls were enrolled in the study. Quality of GMs was assessed from videotapes between 3 and 6 weeks and between 9 and 16 weeks. Neurological outcome was evaluated at least at two years. Results. Seven of the 11 infants had an assessment performed between 3 and 6 weeks: abnormal GMs were observed in all the infants who developed hemiplegia, but one child had abnormal GMs and a normal outcome. All 11 infants had a scorable assessment between 9 and 16 weeks. In all a specific type of GMs, fidgety movements (FMs), were predictive of neurological outcome. The presence of early asymmetries at both 3 - 6 and 9 - 16 weeks was also significantly associated with later signs of hemiplegia. Conclusions. The assessment of GMs after the neonatal period appears to be very useful in the early identification of hemiplegia in infants with cerebral infarction. Whilst the prediction of hemiplegia should be possible from early neonatal MRI brain scans, this facility is not always available. Observation of GMs is a bedside clinical approach that allows confirmation of early prediction from MRI, early rehabilitation if needed and reassurance that neurological outcome will be good where that is appropriate.

Cerebral Infarction↗

PubMed2003

Neonatal cerebral infarction and visual function at school age.

OBJECTIVE: To assess various aspects of visual function at school age in children with neonatal cerebral infarction. PATIENTS AND METHODS: Sixteen children born at term, who had cerebral infarction of perinatal onset on neonatal magnetic resonance imaging (MRI) were assessed using a battery of visual tests. This included measures of crowding acuity (Cambridge Crowding Cards), stereopsis (TNO test), and visual fields. The results of the visual assessment were compared with the type and the extent of the lesion observed on neonatal MRI. RESULTS: Only six of the 16 children (28%) had some abnormalities of visual function on these tests. Visual abnormalities were more common in children with more extensive lesions involving the main branch of the middle cerebral artery and were less often associated with lesions in the territory of one of the cortical branches of the middle cerebral artery. The presence of visual abnormalities was not always associated with the involvement of optic radiations or occipital primary visual cortex. Abnormal visual fields were only found in children who also developed hemiplegia. CONCLUSIONS: Abnormality of visual function is not common in children who had neonatal infarction and, when present, tends to be associated with hemiplegia and more extensive lesions.

Cerebral Infarction↗

PubMed2002

MRI lesions and infants with neonatal encephalopathy. Is the Apgar score predictive?

OBJECTIVE: The aim of this study was to establish whether, in full-term infants presenting with neonatal encephalopathy, the 1 minute Apgar score gives an indication of the presence, site or type of lesions observed on brain MRI in the neonatal period. PARTICIPANTS AND METHODS: The study cohort included 157 full-term infants who had neurological abnormalities during the first 48 hours after delivery. Infants with developmental, genetic, infective or metabolic diagnoses were excluded from the study. The infants were subdivided according to their 1 minute Apgar score into three groups as follows: Apgar score 0 - 3 (n = 108/157, 69 %), 4 - 7 (n = 29, 19 %), 8 - 10 (n = 21, 12 %). Results. Severe and moderate basal ganglia and thalamic (BGT) lesions, with one exception, were only observed in the group with an Apgar score of 3 or below. Minimal BGT lesions were, with one exception, associated with scores below 7 and mainly below 3. However, not all the infants with low Apgar scores had BGT lesions and 28 % of the patients with Apgar scores below 3 had normal scans or only minimal white matter changes. White matter lesions without BGT involvement were equally distributed in the cohort, irrespective of the Apgar scores. Cerebral infarction and scattered white matter haemorrhages were the most common findings in infants with Apgar scores of 4 and above. The Apgar scores were not always predictive of motor outcome at 2 years but the presence and severity of the sequelae mainly reflected the site and severity of MRI findings. CONCLUSIONS: These findings stress the importance of subdividing neonatal encephalopathy into diagnostic categories according to brain lesions if one wishes to study either causative factors or outcome.

Apgar Score↗

PubMed2002

Neurological and perceptual-motor outcome at 5 - 6 years of age in children with neonatal encephalopathy: relationship with neonatal brain MRI.

OBJECTIVE: The aims of this study were 1) to determine the incidence of minor neurological dysfunction and perceptual-motor difficulties in children aged 5-1/2 -- 6-1/2, who had been born full-term but presented with neonatal encephalopathy (NE) and low Apgar scores and 2) to examine the relationships between the presence/absence of these difficulties with neonatal brain MRI. PARTICIPANTS AND METHODS: Sixty-eight full-term infants with one minute Apgar scores less than or equal to 5 and neurological abnormalities during the first 48 hours after birth were included in the study. All children had a neonatal MRI brain scan. Surviving infants were assessed between the age of 5 and 6 years using the Touwen Examination, the Movement ABC and the WPPSI-R. RESULTS: Fifteen of the 68 infants (22 %) died in the neonatal period. Of the 53 surviving infants, 19 (36 %) had cerebral palsy. The remaining 34 were considered normal at 2 years of age but, when assessed at school age, 8 (15 %) had minor neurological dysfunction and/or perceptual-motor difficulties, 1 (2 %) had only cognitive impairment and 25 (47 %) were normal. The outcome largely reflected the pattern of lesions on brain imaging. While 83 % of those with a normal outcome had normal scans or minimal white matter lesions, 80 % of those with minor neurological dysfunction and/or perceptual-motor difficulties had mild or moderate basal ganglia or more marked white matter lesions. CONCLUSION: Continued surveillance is recommended for children with apparently normal outcome at two years of age after NE, particularly when abnormalities are detected on brain MRI.

Age Factors↗

PubMed2001

Neurologic examination in infants with hypoxic-ischemic encephalopathy at age 9 to 14 months: use of optimality scores and correlation with magnetic resonance imaging findings.

OBJECTIVES: To evaluate whether a structured and scorable neurologic examination (The Hammersmith Infant Neurological Examination) correlates with early magnetic resonance imaging findings in a group of infants with hypoxic-ischemic encephalopathy (HIE) and whether the scores of this assessment can predict the locomotor function in these children. STUDY DESIGN: A total of 53 term infants fulfilling the criteria for HIE underwent scanning within 4 weeks from delivery with a 1 Tesla HPQ magnet. The scores from the neurologic examination performed between 9 to 14 months were correlated to the neonatal magnetic resonance imaging findings and to the maximal locomotor function defined at the ages of 2 and 4 years. RESULTS: The scores were always optimal in the infants with normal or minor neonatal magnetic resonance imaging findings. The lowest scores were associated with severe basal ganglia and white matter lesions. All the infants who had a global score between 67 and 78 at 1 year were able to walk independently at 2 years and without restrictions at 4 years. Scores between 40 and 67 were associated with restricted mobility and scores <40 with severely limited self-mobility at 2 and 4 years. CONCLUSIONS: The use of a standardized neurologic optimality scoring system gives additional prognostic information, easily available in the clinic, on the severity of the functional motor outcome in infants with HIE.

Female↗

PubMed2001

Postpartum thiamine deficiency in a Karen displaced population.

BACKGROUND: Before its recognition, infantile beriberi was the leading cause of infant death in camps for displaced persons of the Karen ethnic minority on Thailand's western border. OBJECTIVE: This study aimed to document thiamine status in the peripartum period to examine the current supplementation program and the correlation between the clinical manifestations of thiamine deficiency and a biochemical measure of thiamine status. DESIGN: Women were enrolled prospectively at 30 wk of gestation and were followed up weekly until delivery and at 3 mo postpartum. Thiamine supplementation during pregnancy was based on patient symptoms. RESULTS: At 3 mo postpartum, thiamine deficiency reflected by an erythrocyte transketolase activity (ETKA) > or = 1.20% was found in 57.7% (15/26) of mothers, 26.9% (7/26) of whom had severe deficiency (ETKA > 1.25%). No significant associations between ETKA and putative maternal symptoms or use of thiamine supplements were found. CONCLUSIONS: Biochemical postpartum thiamine deficiency is still common in Karen refugee women. This situation may be improved by educating lactating women to reduce their consumption of thiaminase-containing foods and by implementing an effective thiamine supplementation program.

Adolescent↗

PubMed2001

Combined use of electroencephalogram and magnetic resonance imaging in full-term neonates with acute encephalopathy.

OBJECTIVE: The electroencephalogram (EEG) is widely used in full-term infants with acute neonatal encephalopathy, and its prognostic value has been confirmed by several studies. Magnetic resonance imaging (MRI) of the brain has also been applied in these patients, and increasing numbers of reports affirm its prognostic reliability. The aim of this study has been to investigate the correlation between an early EEG and MRI findings in infants with acute neonatal encephalopathy and to assess the prognostic value of a combination of EEG and MRI findings. PARTICIPANTS AND METHODS: Twenty-five full-term infants had an EEG recorded within the first 72 hours after birth and a neonatal brain MRI scan after the end of the first week. RESULTS: Both EEG and MRI were predictive of outcome. A normal MRI was always associated with normal EEG background activity and normal outcome and severe abnormalities on MRI with marked EEG abnormalities and an abnormal outcome. When the MRI showed moderate abnormalities, the EEG in all cases but one identified patients with normal and abnormal outcome.EEG, MRI, HIE, neurodevelopment.

Brain↗

PubMed2001

Prothrombotic disorders and abnormal neurodevelopmental outcome in infants with neonatal cerebral infarction.

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the occurrence of prothrombotic disorders in a well-characterized cohort of infants with neonatal stroke and to document any association of prothrombotic disorders with the type of infarct seen on magnetic resonance imaging (MRI) and clinical outcome. METHODS: Twenty-four infants with perinatal cerebral infarction confirmed by neonatal MRI were enrolled in the study. All the infants and, when possible, both parents were tested to identify inherited and acquired prothrombotic disorders. RESULTS: None of the infants had a significant bleeding diathesis, but 10 (42%) had at least 1 prothrombotic risk factor. Five children showed heterozygosity for factor V Leiden, and 6 had high factor VIIIc concentrations. There was a striking association between the occurrence of these abnormalities and both the presence of cerebral hemorrhage on MRI and poor neurologic outcome. Eight of the 11 patients (73%) with hemiplegia or global developmental delay had factor V Leiden and/or raised factor VIIIc, whereas only 1 of the 13 patients (8%) with normal outcome had any prothrombotic risk factors. In particular, all 5 infants with factor V Leiden had hemiplegia, compared with only 4 of the 19 infants without factor V Leiden (21%). CONCLUSIONS: These data suggest that the presence of prothrombotic risk factors and, in particular, of the factor V Leiden mutation, is significantly associated with poor outcome after perinatal cerebral infarction.

Activated Protein C Resistance↗

PubMed2000

Neonatal neurological testing in resource-poor settings.

The aim of the study was to design and test a neurological examination for newborns that could be performed reliably by paramedical staff in resource-poor settings. The examination was adapted from a method established by Dubowitz et al., the latest version of which includes an optimality score. The final items in the test were chosen because they were culturally acceptable, could be elicited according to strict but easily comprehensible instructions and because the expected responses could be scored by the descriptions given or by diagrams in the proforma. The shortened examination was easily taught to paramedical staff who achieved a high degree of inter-observer reliability. This shortened version of the examination was piloted by comparing newborns from a Karen refugee camp on the western border of Thailand and from a large maternity hospital in Bangkok with a standardized cohort of newborns in London. The modified shortened version of the test was sufficiently sensitive to identify a number of differences between the cohorts, notably the poor vision performance and markedly reduced tone of the Karen newborns. In conclusion, the test can be used very reliably by paramedical staff and is a useful, simple and portable tool for the neurological assessment of newborn babies where resources are limited.

Allied Health Personnel↗

PubMed2000

Cranial ultrasound abnormalities in full term infants in a postnatal ward: outcome at 12 and 18 months.

OBJECTIVE: To investigate whether cranial ultrasound abnormalities found in low risk full term infants had any influence on neurodevelopmental outcome. METHODS: For 103 infants who had a neurological assessment, a cranial ultrasound examination, and for whom antenatal and perinatal data were collected within 48 hours of delivery, neurodevelopmental status was evaluated at 12 and 18 months. The results of a scored neurological examination and the Griffiths mental developmental scale were correlated with the presence and type of ultrasound abnormality found in the neonatal period. RESULTS: None of the infants with ultrasound abnormalities showed any signs of cerebral palsy or severe developmental delay. There was also no significant difference between the overall neurological and neurodevelopmental scores of the infants with normal and abnormal ultrasound findings. However, when the individual subscales of the Griffiths test were analysed, all infants with bulky choroid or intraventricular haemorrhage had normal scores in all subscales, four of eight with periventricular white matter lesions had low scores on the locomotor subscale, and three of five with asymmetrical ventricles had low scores on the performance subscale. The presence of adverse antenatal and perinatal factors did not affect the outcome in this group. CONCLUSION: Incidental ultrasound abnormality in full term neonates, in particular intraventricular haemorrhage, although common, appear to have a good prognosis. Longer follow up studies are needed to see whether some of these infants, in particular those with white matter lesions, develop dyspraxia or other minor neurological impairments at school age.

Brain↗

PubMed1999

Optimality score for the neurologic examination of the infant at 12 and 18 months of age.

The aim of this study was to develop and validate a simple, quantifiable, neurologic examination for infants between 2 and 24 months of age. The assessment consists of 37 items, divided into 3 sections. The first section includes 26 items assessing cranial nerve function, posture, movements, tone, and reflexes; the second section of 8 items documents the development of motor function, and the third section of 3 items evaluates the state of behavior. We applied this assessment to a cohort of ninety-two 12-month-old infants and forty-three 18-month-old infants, with no known perinatal risk factors. The proforma presented has been designed according to the frequency distribution of the neurologic findings in this cohort. Each item is scored individually, and a global score is the sum of all individual scores. The quantitative score enhances the value of this examination, both in clinical practice and in research settings.

Behavior↗

PubMed1999

Congenital hemiplegia in children at school age: assessment of hand function in the non-hemiplegic hand and correlation with MRI.

The aim of this study was to evaluate whether children with congenital hemiplegia show abnormal hand function on the non-hemiplegic side and whether this, if present, can be related to the type and extent of brain lesions on MRI. Twenty-two children with congenital hemiplegia of age ranging between 4.8 and 12.3 years, were assessed with a clinical and MRI assessment. Clinical assessment included a structured neurological examination, assessment of hand grips and the Movement Assessment Battery for Children which also includes one item assessing speed and accuracy in each hand. The results showed that 64% of the children studied showed some degree of functional impairment of the non-hemiplegic hand. Manual dexterity 1 from the Movement ABC was, in our experience, a more sensitive tool to detect minor functional abnormalities than the evaluation of hand grips. The severity of the impairment on the non-hemiplegic side was not significantly related to the severity of impairment in the hemiplegic hand (p > 0.05). In contrast, a significant association was found with the site of lesions as hand function in the non-hemiplegic hand was always normal in children with unilateral lesion and abnormal in the ones with bilateral parenchymal lesions (p < 0.05). Children with predominantly unilateral lesions but with bilateral ventricular dilatation or periventricular changes showed more variable results.

Brain↗

PubMed1999

Neonatal neurological examination in infants with hypoxic ischaemic encephalopathy: correlation with MRI findings.

Neurological examination and magnetic resonance imaging were performed in the neonatal period in 58 full-term infants who presented with hypoxic-ischaemic encephalopathy. The aim of this study was to evaluate the patterns of neurological abnormalities and their correlation to brain lesions on MRI. The prognostic value of the neurological examination performed at different times in the neonatal period was also evaluated. Our results showed that specific clinical patterns can be observed in infants with HIE and these can be related to the pattern of lesion on brain MRI. In particular, while infants with normal MRI or minimal changes tend to show only minor tone abnormalities after the first week of life, infants with more severe lesions such as basal ganglia lesions show persistent and diffuse neurological abnormalities. Infants with white matter changes but intact basal ganglia show a different clinical pattern with improved sucking reflex and behaviour and less severe tone abnormalities. Our results also suggested that the neurological examination performed after the second week of life is a reliable indicator of outcome in these infants.

Asphyxia Neonatorum↗

PubMed1999

Impaired grip-lift synergy in children with unilateral brain lesions.

Children with spastic hemiplegia have impaired dexterity in the affected extremity. The purpose of the present study was to investigate whether the force co-ordination pattern during precision grip in 13 children between 4 and 10 years of age with predominant unilateral brain lesions is related to manual dexterity and to the location and size of the brain lesion. The force co-ordination pattern was investigated by means of a specially designed object that monitored the isometric fingertip forces applied to the contact surfaces during precision grip. Hand function was measured by means of neurological examination, functional hand-grips and dexterity. Brain lesions were identified by series of ultrasound and MRI scans. Normally, the fingertip forces are applied to the object in the initial phase of the lift in an invariant force co-ordination pattern (i.e. grip-lift synergy), in which the grip and load forces are initiated simultaneously and increase in parallel with unimodal force rate trajectories. A majority of children with unilateral brain lesions had not developed the force co-ordination pattern typical for their age, but produced an immature or a pathological pattern. The developmental level of the grip-lift synergy was determined and quantified according to criteria derived from earlier studies on normally developed children. There was a clear relationship between the developmental level of the grip-lift synergy and impaired dexterity, indicating that proper development of the force co-ordination pattern is important for skilled hand function. The grip-lift synergy correlated with the total extent of lesions in the contralateral cortex and white matter and with lesions in the thalamus/basal ganglia, while no correlation was found for isolated cortical lesions. The results suggest that the neural circuits involved in the control of the precision grip are organized in a parallel and distributed system in the hemispheres, and that the basal ganglia are important during the formation of these circuits. Perinatal lesions in specific cortical motor areas may be compensated for by circuits elsewhere in the grip-lift motor system, while large lesions exclude this possibility.

Brain↗