脑性瘫痪儿童的MRI特征

目的 探讨脑性瘫痪(脑瘫)患儿脑MR／的表现及其与出生胎龄和脑瘫类型的关系。方法 回顾性分析104例脑瘫患儿的病史、l临床与MR／表现。结果 早产与足月儿脑瘫类型构成显著不同,早产儿以痉挛性双瘫多见(占66．O％),而足月儿偏瘫和失调型高于早产儿。104例脑瘫患儿MR／异常率为84．7％,早产和足月儿组MHI异常率差异无显著性。痉挛型双瘫、四肢瘫、偏瘫、手足徐动型和失调型脑瘫MR／异常率分别为89．4％、100％、100％、54．5％和90．O％。31／42例痉挛性双瘫表现为脑室周围白质软化症(PVL),而以早产儿双瘫更多见(90％);各类型脑瘫的MR／异常表现不同,双瘫以PVL为主,徐动型表现为基底节病变或．PVL失调型绝大部分存在先天性小脑发育不全,偏瘫型突出表现为单侧脑损伤。出生胎龄与MRI特点有关,早产儿组以PVL为特征,见于除失调型外的其他脑瘫类型;足月儿脑瘫MR／异常表现变化多且病变广泛。结论MR／有助于评价各型脑瘫的病理特点及其与出生胎龄的关系．对脑瘫病因的推测有帮助。     

Brain lesions in preterms: origin, consequences and compensation

Twenty-nine high-risk preterm born children, from a cohort with cerebral blood flow (CBF) measurements in the first 2 d of life, were examined prospectively at the age of 5.5-7 y neurologically, neuropsychologically and by magnetic resonance imaging (MRI). They were compared to 57 control children in terms of neurology and neuropsychology. Abnormal MRI was found in 19 children. Low oxygen delivery to the brain was found in 63% of them, in contrast to 12.5% in those with normal MRI, indicating neonatal hypoxia-ischemia as an important factor. The MRI abnormalities were mainly periventricular lesions (n = 19), especially periventricular leucomalacia (PVL, n = 17). Three of the very preterm children had severe cerebellar atrophy in addition to relatively mild periventricular abnormalities. MRI showed specific morphological correlates for the major disabilities, e.g. spastic CP (involvement of motor tracts), mental retardation (bilateral extensive white matter reduction or cerebellar atrophy) and severe visual impairment (severe optic radiation involvement). A morphological correlate for minor disabilities, i.e. functional variations in motor performance or intelligence, was not found, with the exception that symptoms of attention deficit hyperactivity disorder were related to mild MRI abnormalities. This could mean that with respect to cognitive functions, mild or unilateral periventricular MRI lesions could be compensated. However, as among preterms without mental retardation (n= 19), IQ was generally and significantly lower than in the control group; other, more chronic pathogenetic factors, not detectable by MRI alone, may play a role.     

DTI correlates of cognition in term children with spastic diplegic cerebral palsy

Background and aimsPresently, there is no published study that shows association between cognition and white matter injury in spastic cerebral palsy. We aimed to correlate cognitive functions with diffusion tensor imaging derived metrics in spastic diplegic children.MethodsTwenty-two term children with spastic diplegia and 22 healthy controls were recruited. All patients were graded on the basis of gross motor function. The Indian children intelligence Test was used to quantify cognition and diffusion tensor imaging was used to quantify microstructural changes in various white matter regions. Diffusion tensor imaging metrics were quantified by placing regions of interests in different white matter regions like corona radiata, anterior limb of internal capsule, posterior limb of internal capsule, mid brain, pons, medulla, genu, splenium, temporal white matter, parietal white matter, frontal white matter and occipital white matter.ResultsSpastic diplegic children showed significantly lower neuropsychological test scores as compared to controls. A significantly decreased fractional anisotropy values were observed in corona radiata, anterior limb of internal capsule, posterior limb of internal capsule, mid brain, pons, medulla, genu, splenium and occipital white matter; however significantly increased mean diffusivity values were observed in corona radiata, anterior limb of internal capsule, posterior limb of internal capsule, mid brain, pons and genu in spastic diplegic as compared to controls. A significant positive correlation in fractional anisotropy and negative correlation in mean diffusivity was observed with neuropsychological test scores.ConclusionThese results suggest that these imaging metrics may be used as a biomarker of cognitive functions in term children with spastic diplegia.     

Very-low-birth-weight, preterm infants with or without intracranial hemorrhage. Neurologic, cognitive and cranial MRI correlations at 4-8-year follow-up

Fourteen very-low-birth-weight (VLBW) preterm infants with and without intracranial hemorrhage (ICH) were prospectively followed from birth to 4 to 8 years for the purpose of determining neurologic and cognitive sequelae associated with ICH severity and to correlate outcomes with brain morphology as determined by Magnetic Resonance Imaging (MRI). Intracranial hemorrhage was documented by cranial ultrasonography performed in early life. Follow-up assessments included neurologic and psychometric examinations and cranial MRI scans. Of six children with no ICH, five had normal results on all three follow-up measures. Three children with Grade I-II ICH had mild to moderate neurologic and cognitive sequelae with focal white matter MRI abnormalities. Five children with Grade III-IV ICH had severe neurologic, cognitive, and MRI deficits, including MRI regional and diffuse white matter abnormalities and/or cortical atrophy. Focal and diffuse neurologic deficits correlated with the extent of MRI morphologic abnormalities. Results of this study indicate that ICH severity correlated with outcomes in children at follow-up; the more severe the ICH, the more adverse the neurologic, cognitive, and MRI results. MRI white matter abnormalities were present in all children with any degree ICH, while ventriculomegaly was seen only in severe ICH (Grade III-IV ICH). Neurologic deficits correlated with MRI structural abnormalities.     

Early diagnosis of spastic diplegia, spastic hemiplegia, and quadriplegia

A retrospective study examined early neurodevelopmental behaviors of children with spastic diplegia, spastic hemiplegia, and quadriplegia (spastic, athetoid, or mixed) who had been followed up longitudinally in a high-risk infant follow-up clinic. Compared with peers with normal outcomes, children with all three types of cerebral palsy had significantly lower scores on the Bayley Mental Scale at 4 months of age; children with hemiplegia and quadriplegia also scored significantly lower on the Bayley Motor Scale. On the Movement Assessment of Infants at 4 months of age, the children with hemiplegia and quadriplegia showed significantly higher risk scores than the nonhandicapped group. The Movement Assessment of Infants was more than three times as sensitive as the Bayley Motor Scale in detecting motor abnormalities in 4-month-old infants with diplegia and more than twice as sensitive in detecting early abnormalities of hemiplegia. At 1 year of age, however, the Bayley Motor Scale was extremely sensitive in picking up motor deficits in children with all three types of cerebral palsy.     

Magnetic resonance imaging and T2 relaxometry of cerebral white matter and hippocampus in children born preterm

The objective of this study was to determine whether intelligence and minor motor impairments in children who are born preterm without major disability are associated with cerebral white matter (CWM) and hippocampal abnormalities on magnetic resonance imaging (MRI). A total of 103 preterm children were studied at age 7 y with detailed magnetic resonance brain scans, including a T2-mapping sequence from which T2 relaxation times of the CWM and hippocampal formations were calculated. All of the children had no major motor disability, attended normal school, and had undergone assessment of IQ and a test for minor motor impairment (MMI). Twenty children had visible lesions on MRI, which were associated with lower IQ and more frequent MMI. Mean (SD) IQ was 90 (14.1). Twenty-five children were shown to have MMI (Movement ABC at below the fifth centile). This group was shown to have significantly longer T2 relaxation times for CWM (mean difference 2.1 ms right, 3.1 ms left) but not the hippocampus than the children without MMI. These differences persisted when only children without visible lesions on scans were considered (mean difference 1.5 ms bilaterally). There was no significant correlation between IQ and T2 relaxation times. Children who are born preterm without subsequent major neurodisability may, in addition to visible lesions on MRI scans, have a diffuse abnormality of CWM, manifest as an increase in T2 relaxation time. This abnormality shows a close correlation with minor motor impairment but not with full-scale IQ.     

A comparative magnetic resonance imaging study of the corpus callosum in neurologically normal children and children with spastic diplegia

To determine the extent of brain damage in children with spastic diplegia, we analyzed the true midsagittal magnetic resonance imaging findings for the corpus callosum in 43 children with spastic diplegia and in 69 neurologically normal children. In the normal children, the thicknesses of the genu, midbody, splenium and the entire corpus callosum were found to increase with age, while the ratios of the thickness of the splenium and of the midbody to the length were constant, regardless of age. Both ratios were significantly reduced in diplegic children and the ratio for the splenium was highly correlated with the extent of motor impairment. Assessment of the morphometric changes in the corpus callosum using magnetic resonance imaging may contribute to the determination of the extent of brain damage in diplegic children.     

CT and MR patterns of hypoxic ischemic brain damage following perinatal asphyxia

The objectives were to study the clinical and neurological abnormalities in children with cerebral palsy and to attempt to correlate the signs with radiological abnormalities detected by CT scan and/or MRI of the brain. In a prospective, hospital-based study, 65 children with cerebral palsy were examined neurologically and their perinatal history was reviewed. Their cranial CT scan, and/or magnetic resonance images were studied. The association between the gestational ages, perinatal history, neurological deficits, and the radiological appearances were studied. Of the 24 preterm-born and 41 term-born children, 23 had spastic diplegia; 57 per cent of these children has significant periventricular leucomalacia, which was more common among preterm-born children. Of the 13 children with hemiplegia, 12 had unilateral lesions on neuroimaging. Spastic tetraplegia was associated with extensive, bilateral, diffuse brain damage. Extrapyramidal cerebral palsy was far more common among term-born infants and 80 per cent of these showed significant abnormalities in the basal ganglia region. Ataxic cerebral palsy was an uncommon variety and there was no significant correlation between neurological signs and abnormalities on brain imaging. In conclusion, the radiological findings were closely related to the type of cerebral palsy and the neurological deficit except in the ataxic type. We believe that CT and MRI imaging are helpful in understanding the pathology and the timing of the lesion in cerebral palsy.     

The Changing Panorama of Cerebral Palsy in Sweden

ABSTRACT. The prevalence of cerebral palsy (CP) in Swedish infants born in the four-year period 1979–82 is reported and related to the prevalence in infants bom during the twenty-year period 1959–78. In 1979–82 it was 2.17 per 1000 livebirths, 1.23 for children bom at term and 0.94 for preterms, which means that the rising trend since the beginning of the 1970s persisted. The most pronounced rise, from 0.18 per 1000 livebirths in the period 1967–70 to 0.67 in 1979–82 was found in the subgroup of preterms with spastic/ataxic diplegia. The severity of motor disability and the relative frequency of mental retardation, infantile hydrocephalus and epilepsy among preterm CP children successively increased over the same period of time. The livebirth prevalence of CP in term infants increased slightly but non-significantly during the period 1967–82. The birthweight-specific prevalence of CP per 1000 newborns surviving the first week of life increased in all birthweight groups during the period 1967–82, significantly for birthweights below 1500 g and over 2 500 g. The rising prevalence of CP was concomitant with a parallel fall in perinatal mortality, especially in very preterm infants. In the 1980s, severely multi-handicapped, very preterm children, only exceptionally seen among CP children born in the 1960s and 1970s, has become a matter of concern.     

Very preterm infants at fourteen years: relationship with neonatal ultrasound brain scans and neurodevelopmental status at one year

A follow-up study was carried out on a cohort of 1142 very preterm (< 33 weeks) survivors who had ultrasound (US) brain scanning from birth. Follow-up was continued into adolescence, and included magnetic resonance imaging (MRI) of the brain at 14–15 y. Neonatal US findings and neurodevelopmental status at 1 y predicted outcome at 8 and 14 y, including cognitive development, poor inter-hemispheric interaction and school performance. MR brain imaging indicated that neonatal US accurately identified serious, permanent lesions in the brains of these very preterm infants, although US failed to recognise a large proportion of the abnormalities detected in adolescence by MRI. Atrophy of the corpus callosum was one of the commonest findings on MRI brain scans, supporting the hypothesis that damage to this important commissure may account for the poor school performance reported in very low birthweight infants.     

Brain lesions in preterm infants: initial diagnosis and follow-up

Children surviving premature birth present with a wide spectrum of motor, sensory and cognitive disabilities, ranging from slight motor deficits, school difficulties and behavioural problems to cerebral palsy and mental retardation. The anatomic and functional substrate of these problems can be investigated using a variety of imaging techniques. Cranial US coupled with colour Doppler is a well-established method for the initial diagnosis of intraventricular haemorrhage, parenchymal haemorrhagic infarct and periventricular leukomalacia. MRI is useful for the follow-up study of brain maturation. Conventional T1- and T2-weighted sequences, magnetization transfer and diffusion tensor imaging coupled with sophisticated tools of tissue segmentation and analysis at a voxel level offer substantial anatomic and functional information on pathological conditions that define the prognosis of preterm infants.     

The sequelae of neonatal brain injury

The neonatal brain is very vulnerable to injury due to its relatively large size, rapid rate of development and immature immunological systems. Injury at this time often results in lifelong neuro-developmental sequelae such as cerebral palsy, learning difficulties and sensory deficits. In the term brain injury is most commonly due to hypoxia–ischaemia during labour, but hyperbilirubinaemia, trauma, thrombosis and infections remain important causes.In the preterm infant, because of immaturity, the pattern of injury is different with forms of white matter damage predominating. Germinal matrix haemorrhage, parenchymal infarction and forms of periventricular leucomalacia predominate. Preterm white matter damage often leads to altered or reduced development of cortical grey matter subsequently. All forms of cerebral palsy are seen in preterm children, but spastic cerebral diplegia is the commonest. Minor motor impairments in childhood are also very common as are behavioural disorders.Exact prognoses for infants with neonatal brain lesions are difficult to make owing to the fact that more than one lesion may co-exist in the same infant.     

Caudate and hippocampal volumes, intelligence, and motor impairment in 7-year-old children who were born preterm

Children who survive very preterm birth without major disability have a high prevalence of learning difficulty, attention deficit, and minor motor impairment (MMI). To determine whether these difficulties are associated with structural brain abnormalities, we studied 105 preterm children (<32 wk) at 7 y with tests of IQ and MMI (Movement ABC) and detailed magnetic resonance brain scans. Scans were assessed qualitatively for visible cerebral lesions. Volume measurements of the caudate nuclei and hippocampal formations were made. Total brain volume (TBV) was estimated from the head circumference. Qualitative assessment of the scans showed evidence of cerebral lesions in 20 (19%), which were associated with lower IQ and more frequent MMI. IQ correlated with right and left caudate volume (Spearman's rho 0.304 and 0.349; p < 0.01). This association persisted (except for verbal IQ) when caudate volume was expressed as a percentage of estimated TBV to allow for overall brain size. No significant correlations with hippocampal volumes were observed. These differences persisted when only scans from children without visible lesions on scan were considered. MMI was significantly associated only with TBV and was more common in children with evidence of thinning of the posterior corpus callosum, although most children with MMI have a normal corpus callosum. Lower IQs in children who were born preterm are related to poorer development of the caudate relative to the rest of the brain, independent of other lesions. These findings suggest abnormal brain development after perinatal injury or postnatal nutritional deficits is responsible for cognitive deficits in preterm children.     

Results of parenchymal and angiographic magnetic resonance imaging and neuropsychological testing of children after stroke as neonates

We describe the long-term follow up of infants after neonatal stroke of the middle cerebral artery (MCA). Stroke was diagnosed by CT scan in eight full-term neonates. Three dimensional (volume) magnetic resonance angiography (MRA) is a noninvasive technique that images the arterial vessels without contrast agents. All patients, aged from 1.5 to 8.4 years, were investigated by MRI and MRA and by neuropsychological tests. Cognitive development was investigated by intelligence tests, tests of visual perception, motor and language development. Out of the eight patients, seven had a retarded mental and motor development, and 50% of the children were treated for epilepsy. Seven patients had a spastic hemiparesis. Seven out of eight children showed major cognitive deficits. In all patients, MRI revealed clear parenchymal defects with variable distribution patterns. MRA studies showed abnormalities corresponding to the expected vascular distribution. Children with complications at delivery, with seizures, and an interruption of the main stem of MCA as demonstrated on MRA had the least favourable long-term follow up prognosis with severe cognitive delays.     

Follow-up at age 10 years in ELBW children — Functional outcome,brain morphology and results from motor assessments in infancy

Background

Extremely-low-birth-weight (ELBW) children without severe brain injury or CP are at high risk of developing deficits within cognition, attention, behavior and motor function. Assessing the quality of an infant's spontaneous motor-repertoire included in Prechtl's General-Movement-Assessment (GMA) has been shown to relate to later motor and cognitive functioning in preterm children without CP.

Aims

To investigate functional outcome and cerebral MRI morphometry at 10 years in ELBW children without CP compared to healthy controls and to examine any relationship with the quality of infant-motor-repertoire included in the GMA.

Study design

A cohort-study-design.

Subjects

31 ELBW children (mean birth-weight: 773 g, SD 146, mean gestational age 26.1 weeks, SD 1.8) and 33 term-born, age-matched controls.

Outcome measures

GMA was performed in ELBW children at 3 months corrected age. At 10 years the children underwent comprehensive motor, cognitive, behavioral assessments and cerebral MRI.

Results

The non-CP ELBW children had similar full-IQ but poorer working memory, poorer motor skills, and more attentional and behavioral problems compared to controls. On cerebral MRI reduced volumes of globus pallidus, cerebellar white matter and posterior corpus callosum were found. Cortical surface-area was reduced in temporal, parietal and anterior-medial-frontal areas. Poorer test-results and reduced brain volumes were mainly found in ELBW children with fidgety movements combined with abnormal motor-repertoire in infancy.

Conclusion

Non-CP ELBW children have poorer functional outcomes, reduced brain volumes and cortical surface-area compared with term-born controls at 10 years. ELBW children with abnormal infant motor-repertoire seem to be at increased risk of later functional deficits and brain pathology.     

新生儿颅脑磁共振检查临床实践的专家共识

颅脑磁共振成像（magnetic resonance imaging,MRI）技术的迅速发展为新生儿脑发育评估、脑损伤诊断和预后判断提供了客观依据,临床应用日益广泛。中国医师协会新生儿科医师分会基于国内外现有研究证据,结合临床实践经验,为新生儿颅脑MRI的适应证和临床实践规范制定专家共识,主要内容包括：（1）疑似新生儿缺氧缺血性脑病、颅内感染、脑卒中,以及原因不明惊厥者应行颅脑MRI;颅脑MRI不纳入早产儿常规脑损伤筛查管理,当颅脑超声筛查有明确损伤证据时应行颅脑MRI进一步评估;对于颅脑超声未见异常的超早产儿和超低出生体重儿,建议在纠正胎龄足月时行颅脑MRI;（2）新生儿颅脑MRI应尽量在非镇静状态下完成;（3）过程中需密切监测生命体征,优化检查条件,保障安全,危重患儿检查需严格评估检查的必要性,可应用磁共振兼容的转运培养箱和呼吸机;（4）目前新生儿颅脑MRI检查可选1.5 T或3.0 T设备,应用新生儿颅脑专用线圈以提高信噪比;常规扫描序列选择应遵循：至少包含轴位T1加权像、轴位T2加权像、弥散加权成像,以及矢状位T1加权像或T2加权像;（5）建议采用结构化或分级报告系统,通过双人审签报告、多中心协作等方式提高报告可靠性。     

Constructional dyspraxia in preterm diplegia: isolation from visual and visual perceptual impairments

Objective: To evaluate ophthalmological profiles, visual perception and constructional function in preterm children with spastic diplegia (SD) and to clarify their neuropsychological deficits in comparison with a control group. Methods: Thirty-five SD and 34 control children were investigated for visual acuity, eye position, stereoacuity, depth perception, visual perception, visuo-spatial construction and constructional praxis. Each of the results was compared among the four groups as SD with and without strabismus, and control with and without strabismus. Results: Strabismic SD showed worse visual acuity, worse stereoacuity and worse depth perception than the other groups. Constructional dyspraxia was detected in 94. 1% of SD either with or without strabismus, while it was rare in the control group. There was no significant contribution of visual acuity, eye position, stereoacuity or depth perception to constructional dyspraxia by stepwise multiple linear regression analysis. Conclusion: Strabismic preterm SD children are at high risk for visual dysfunction. Constructional dyspraxia was frequently found in SD children and may be a dysfunction isolated from ophthalmological and visual perceptual dysfunctions.     

Neonatal MRI in preterm infants with periventricular leukomalacia and mild disability

Background: The aim of the present study was to describe the neonatal magnetic resonance imaging (MRI) findings of preterm infants with periventricular leukomalacia and mild neurological disability. Methods: MRI findings at term equivalent were retrospectively investigated in eight preterm infants with mild disability and periventricular leukomalacia diagnosed on MRI in infancy. Results: Linear, spotted, or macular areas of hyperintensity on T1‐weighted imaging and hypointensity on T2‐weighted imaging were identified in all subjects in the white matter lateral to the body of the lateral ventricle. No cystic lesions were seen. These findings were more widespread and more clearly visualized on T2‐weighted imaging than T1‐weighted imaging. Conclusions: Linear, spotted, or macular lesions that are hyperintense on T1‐weighted imaging and hypointense on T2‐weighted imaging are possibly compatible with periventricular leukomalacia.     

儿童基底节对称性病变28例临床分析

目的 探讨和分析儿童基底节区对称性病变的发病机制、临床特点和预后.方法 2003年3月至2008年4月我院收治具有脑损害表现、同期CT/MRI扫描示双侧基底节区对称性低密度和(或)MRI T1WI呈对称性低信号、T2WI呈高信号患儿共28例,对其临床资料进行回顾性分析和总结.结果 甲基丙二酸血症3例、α-酮戊二酸尿症2例、高乳酸血症1例,患儿首发症状为发热、咳嗽和(或)呕吐、腹泻,并迅速进展为抽搐、昏迷,伴酸中毒、血乳酸和丙酮酸增高;7月龄高乳酸血症1例,患儿运动发育落后、喂养困难、反复惊厥发作;VitB_1缺乏性脑病1例,患儿单纯母乳喂养、哭声嘶哑、肌无力、抽搐、VitB_1肌注后症状改善明显;肝豆状核变性18例,患儿肌张力增高、震颤、流涎、共济失调、吐字不清、记忆力下降,其中13例伴有肝脏肿大,10例脾脏肿大,肝硬化和脾功能亢进各2例;霉甘蔗中毒和煤气中毒各1例,患儿认知和运动功能障碍恢复缓慢.结论 儿童基底节区对称性病变病因复杂、症状多样,结合病史、临床特点和影像学特征、实验室检查包括代谢病筛查,可早期明确病因并及时合理治疗,有助于改善预后.     

Impact of cerebral palsy in patients discharged from neonatal intensive care units

AIM: The aim of this study was to assess the impact and the peculiarities of cerebral palsy (CP) in children discharged from our neonatal intensive care unit (NICU) from January 1998 to April 2004. METHODS: A total of 2 303 children were discharged from our NICU during this period and 1 912 were followed up for 1 year through neurological examination (traditional, Brazelton, general movements) and cranial ultrasound (US); high-risk newborns were evaluated with brain magnetic resonance imaging (MRI) too. RESULTS: In 65 children (3.4% of the follow-up group) were diagnosed CP, and classified as follows: 21 (32%) diplegia, 19 (29%) quadriplegia, 20 (31%) hemiplegia, 4 (6%) double hemiplegia, 1 (2%) dyskinetic form. In diplegia and quadriplegia prevailed low birth weight infants (less than or equal to 2,500 g) and preterm infants, while in hemiplegia prevailed normal birthweight infants (greater than 2,500 g) and infants at term. The main MRI findings were: in diplegia 82% periventricular white matter lesions; in quadriplegia 94% periventricular and/or subcortical white matter lesions; in hemiplegia 95% bilateral periventricular or subcortical white matter lesions, predominating on contralateral cerebral hemisphere; in double hemiplegia 100% periventricular and/or subcortical white matter lesions, 100% enlargement of subarachnoid spaces; in dyskinetic form 100% basal ganglia lesions. CONCLUSIONS: The impact of CP in children discharged from our NICU, in agreement with the literature, is higher than in the total population of newborns, thus it is very important to evaluate carefully high-risk newborns during hospitalization and follow-up, through neurological examination and radiologic imaging (US, MRI), for an accurate and early treatment.