Computerized tomography in cerebral-palsied children

A systematic review of neuroimaging for cerebral palsy

The American Academy of Neurology now recommends that all cases of cerebral palsy of unknown origin undergo neuroimaging. Controversy surrounds this recommendation because of concerns about the adequacy of the supporting evidence. This article reviews the evidence provided by magnetic resonance imaging (MRI) and computed tomography (CT) imaging studies in cerebral palsy and discusses the potential benefits of imaging, techniques in current use, and future directions, with a focus on improving etiologic understanding. Most (83%) children with cerebral palsy have abnormal neuroradiological findings, with white matter damage the most common abnormality. Combined gray and white matter abnormalities are more common among children with hemiplegia; isolated white matter abnormalities are more common with bilateral spasticity or athetosis, and with ataxia; isolated gray matter damage is the least common finding. About 10% of cerebral palsy is attributable to brain malformations, and 17% of cerebral palsy cases have no abnormality detectable by conventional MR or CT imaging. Although neuroimaging studies have increased our understanding of the abnormalities in brain development in cerebral palsy, they are less informative than they might be because of 4 common problems: (1) inappropriate assignment of etiology to morphologic findings, (2) inconsistent descriptions of radiologic findings, (3) uncertain relationship of pathologic findings to brain insult timing estimates, and (4) study designs that are not based on generalizable samples. Neuroimaging is not necessarily required for diagnosis of cerebral palsy because the disorder is based on clinical findings. The principal contribution of imaging is to the understanding of etiology and pathogenesis, including ruling in or out conditions that may have implications for genetic counseling, such as malformations. In the future, as more sophisticated imaging procedures are applied to cerebral palsy, specific morphologic findings may be linked to etiologic events or exposures, thus leading to potential pathways for prevention.

Computerized tomography scan of the brain in a community study of neurological impairment in Kenya

Neurological impairment is common in resource-poor countries, but its causes are not clear. Computerized tomography (CT) of the brain has been used to determine the cause of brain insults that may manifest as neurological impairments. The authors conducted a community survey in Kilifi of 10 218 children aged 6 to 9 years to detect neurological impairment. From this survey, 34 children were identified, of whom 16 had motor deficits, 11 complex partial seizures, 4 microcephaly or macrocephaly, and 3 severe developmental delay. These children were assessed with elicitation of history, physical examination, and CT scan of the brain. Sixteen (47%) of the scans showed abnormalities: cerebral atrophy (n = 9), schizencephaly (n = 3), periventricular leukomalacia (n = 2), porencephalic cyst (n = 1), and agenesis of the corpus callosum (n = 1). The minimum prevalence of abnormalities on the CT scan of the brain is 1.56 of 1000, and the prevalence of schizencephaly is 0.29 of 1000. Motor impairments were more likely to show abnormality than the other indications. CT abnormalities are common in children with neurological impairment in Kenya, but the appearances did not identify a major cause.

Symptomatic epilepsy in children with poroencephalic cysts secondary to perinatal middle cerebral artery occlusion

BACKGROUND

Perinatal cerebral artery occlusion is responsible for ischemic cerebral infarction leading to brain cavitation and gliosis; the territory of the middle cerebral artery is most frequently involved. The resulting poroencephalic cysts are frequently associated with hemiplegia and epilepsy; that can be managed medically in most cases, only 6-7% of them being refractory to medical treatment. This particular subset of congenitally hemiplegic children will be possible candidates for electrophysiological investigation and eventually for resective surgery. Whatever the kind of surgical treatment, surgery should be performed as soon as possible to optimize functional brain reorganization.

CLINICAL MATERIAL

Twelve children with poroencephalic cysts and refractory epilepsy were studied and operated on at the Divisions of Child Neurology and Pediatric Neurosurgery, the Catholic University Medical School, Rome. The hemiparesis ranged from mild to moderate; the developmental delay was of mild degree in three cases, moderate in four cases and severe in the remaining five. Behavioral disorders were observed in patients with mental retardation; two of them also manifested autistic features. All the children presented with a severe epileptic syndrome (starting almost invariably during the first year of life); six patients presented with a West syndrome followed by symptomatic partial epilepsy; the other six presented with partial epilepsy, followed in two cases by continuous spike-waves during sleep. The electroencephalograph (EEG) recordings disclosed focal unilateral interictal epileptiform abnormalities that usually corresponded to the side of the cystic lesion; however, paroxysmal activity often spread synchronously over the contralateral hemisphere. The selection of candidates for surgical treatment was based on neuroimaging and video-EEG monitoring; in particular, we did not use invasive intraoperative neurophysiologic techniques. The convergence of neuroimaging and neurophysiologic findings guided us in performing a limited cortical excision corresponding to the malacic cortex (cyst "membrane").

RESULTS

All the patients underwent excision of the cyst wall. Careful attention was paid not to enter the body of the lateral ventricle to avoid ventriculo-subarachnoid fistulas, eventually responsible for subdural hygroma or cerebrospinal fluid leak. There was one surgery-related death secondary to disseminated intravascular coagulation, following an otherwise uneventful surgical procedure. An elevated systemic blood pressure, secondary to repeated adrenocorticotropic hormone therapy, can represent a possible concurrent factor for this event. No major complications were recorded among the remaining 11 children. Seizure control was excellent in all the 11 survivors in the early postoperative period. Two children presented a relapse of seizures, after an initial improvement, respectively 3 and 4 years after the operation. These two children underwent subsequently a functional hemispherectomy. Overall, seizure outcome was excellent in all the cases. Seven patients (including the two who underwent functional hemispherectomy) are seizure-free (Engel's class Ia), and in one of them antiepileptic therapy has been weaned. In the remaining five children, seizures are sporadic and definitely improved (Engel's class II). An improvement of developmental delay, in particular of cognitive competence, was registered in 8 out of the 11 patients. Two of the four severely retarded children, who also presented behavioral abnormalities, did not show any cognitive improvement, whereas some mild improvement of their basal abilities was demonstrated in the other two. All the remaining children, even though maintaining a moderate retardation, definitely improved their abilities; in particular, one of them reached an almost borderline level. The three patients with unchanged neurodevelopmental delay presented also persistent seizures. On the other hand, two children with persistent seizures presented neurodevelopmental improvement.

CONCLUSIONS

Simple surgical excision of the cyst "membrane" of epileptogenic poroencephalic cysts can represent an excellent means to control epilepsy in affected children. However, postoperative seizure persistence and late recurrences, although rare, do not allow to exclude that hemispherectomy or partial resections (based on electrocorticography findings) might represent the good answer at least in some cases.

Assessment of visuoperceptual disturbance in children with spastic diplegia using measurements of the lateral ventricles on cerebral MRI

The authors estimated perceptual disturbance in children with spastic diplegia from the difference between the visual and performance IQ scores (VIQ-PIQ) on the Wechsler Intelligence Scale for Children-Revised (WISC-R), having found a strong negative correlation between this score and the PQ obtained on the Frostig Developmental Test of Visual Perception (DTVP). The ratio of the areas of the posterior horns to the anterior horns (P/A) correlated negatively with visuoperceptual disturbance. This ratio can therefore be used to assess perceptual disturbance at an early age in children with spastic diplegia.

Congenital hemiparesis and periventricular leukomalacia: pathogenetic aspects on magnetic resonance imaging

The authors report on the clinical examination and magnetic resonance imaging (MRI) of 41 children (29 term and 12 preterm) whose diagnosis of congenital hemiparesis was confirmed after the first year of life. Periventricular leukomalacia was the most predominant MRI finding (found in 15 term and eight preterm infants). The uniform pattern of lesions observed through MRI (without clear correlation with gestational age) suggests a common aetiopathogenesis in this subgroup. Comparison of these MR images with the periventricular leukomalacia observed in preterm children with spastic diplegia supports the thesis that ischaemia occurring between the 28th and 35th weeks of gestation could be the main cause.

Surgical indication in children with congenital hemiparesis

Nine children with perinatal occlusion of the middle cerebral artery, resulting in unilateral enlargement of one lateral cerebral ventricle associated with cortical atrophy and subcortical cavity formation, were operated on because of intractable epilepsy. All subjects exhibited mild to severe hemiparesis, localized in the right side of the body in six instances and in the left side in the three cases. All but one patient presented with some degree of psychomotor retardation. The surgical treatment consisted of the removal of the atrophic cerebral cortex. One child died after surgery because of disseminated intravascular coagulation. All the remaining eight children benefited from the operation, with a decrease in the hypertonia of the affected limbs and an improvement in dexterity and gait as well as in intellectual performance. Five patients could be considered seizure-free following the surgical treatment, and the remaining three experienced a significant reduction in the frequency of the seizures.

Computed tomography in fetal methylmercury poisoning

Cerebral computed tomography was studied in eight patients with fetal methylmercury poisoning. All patients had evidence of prenatal exposure to methylmercury and showed psychomotor retardation. All of them had abnormal computed tomography findings. The most common finding was sulcal and ventricular enlargement, with or without cisternal enlargement. These findings indicated generalized cortical and subcortical maldevelopment. The distribution of sulcal and fissural enlargement did not show specific dominance in central sulcus, calcarine fissure or cerebellum. This distribution contrasts with the location of focal atrophy present in adult methylmercury poisoning. The computed tomography findings were relatively mild compared with the clinical features and were not distinct from those in cerebral palsy.

MRI of patients with cerebral palsy and normal CT scan

Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP.

Magnetic resonance imaging in athetotic cerebral palsied children

The magnetic resonance findings in 22 children with athetotic cerebral palsy were studied. Sixteen had perinatal asphyxia, two had neonatal jaundice, and four had no association with predisposing conditions. In six of the children, symmetrical high intensity areas were found in both the thalamus and putamen in T2-weighted images. In five children they were seen only in the thalamus, and in another one only in the putamen. In six children, symmetrical periventricular high intensity areas were seen. In seven of the subjects, no abnormal magnetic resonance findings were seen. Magnetic resonance lesions, possibly caused by asphyxia, were found in the basal ganglia, thalamus and/or cerebral white matter in 14 of 16 children. Three children with lesions only in the cerebral white matter had mild motor abnormality, and six children with lesions in both the thalamus and putamen did not have mild abnormality.

Serial magnetic resonance imaging in neonatal hypoxic-ischemic encephalopathy

We prospectively performed magnetic resonance imaging (MRI) studies during the neonatal period, and at 4 and 8 months of age, on 15 term infants with hypoxic-ischemic encephalopathy, and compared the results with their neurodevelopmental outcome at 18 months of age. Cerebral palsy developed in nine infants, two infants were classified as having abnormalities of tone and delayed motor milestones that were suggestive of cerebral palsy, and four infants were normal. Structural abnormalities, delayed myelination, or a combination of the two were detected with MRI at 8 months of age in all nine infants with later development of cerebral palsy. Three of the four normal infants and one infant with suggestive abnormalities had normal serial MRI findings. Each of the remaining two infants (one normal, one with suggestive abnormalities) had isolated persistent ventricular dilation on all three MRI studies. Our results suggest that 8 months appears to be the earliest time at which MRI findings correlate well with later adverse neurodevelopmental outcome in this population.

Morphology of cerebral lesions in children with congenital hemiplegia. A study with computed tomography

This study has analysed the results of CT scans of the brains in children with congenital hemiplegia. The material consists of 111 out of a total of 151 children with this cerebral palsy syndrome in a population-based series. We have classified the morphological findings in five groups. The groups are designed to reflect the phase of maturation of the brain when the insult happened. The groups are: 1. Maldevelopment, 2. Periventricular atrophy, 3. Cortical-/subcortical atrophy, 4. Miscellaneous, 5. Normal. In contrast to previous reports we found a high proportion (17%) with maldevelopment. However the dominating morphological pattern was periventricular atrophy, consistent with a hypoxic-ischemic insult to the immature brain, seen in 42%. Cortical and/or subcortical atrophy was found in 12%. Three children (3%) presented with morphological patterns not possible to classify. The group with no pathology according to CT was 26%.

Rehabilitation management of children with spastic diplegic cerebral palsy

Spastic diplegia has been recognized as the type of cerebral palsy most frequently associated with prematurity. Due to constantly improving neonatal care in developed countries, more and smaller premature infants are surviving, and the number of spastic diplegic children can be expected to increase. This paper reviews the incidence, pathophysiology, and associated handicaps of patients with this type of cerebral palsy. The role of the physiatrist and aspects of traditional management are discussed. Recent advances in treatment of spasticity and lower extremity bracing are stressed as they seem to be particularly suitable to spastic diplegic patients.

Computed tomographic findings in children with spastic diplegia: correlation with the severity of their motor abnormality

Computed tomographic findings of 46 children with spastic diplegia examined at nine months to three years of age corrected for preterm births were analyzed. Both the size of the lateral ventricles measured by the width of the anterior horns, and the volume of the extracerebral low-density areas were enlarged in some patients. Both enlargements did not, however, correlate to the severity of the motor abnormality in the patients. The low-density areas of the periventricular white matter, especially adjacent to the trigone, were reduced in many children, probably due to the atrophy of the cerebral white matter having periventricular leukomalacia. The anterior expansion of the white matter reduction from the trigone corresponded to the severe motor abnormality in the children with spastic diplegia.

Lobar holoprosencephaly presenting as spastic diplegia

A child with lobar holoprosencephaly presented with spastic diplegia and mild mental retardation, compounded by attention deficits and hyperactivity. His facial features were normal, and except for borderline microcephaly, there were no other predictors of holoprosencephaly. This patient represents the mild end of the spectrum of the holoprosencephaly malformation complex, which seems to be under-represented in the medical literature. Holoprosencephaly does not appear to have been described previously in association with spastic diplegia. This patient also illustrates the value of CT scans of the head of patients with neurological findings, without specific etiology.

Hemiplegic cerebral palsy. Aetiology and outcome

Hemiplegic cerebral palsy (CP) was studied in a retrospective population-based series of 169 cases from the South-western Swedish health care region covering the birth years 1969-78. The purpose was to analyse the prevalence, aetiology and neuro-developmental outcome in children born preterm and at term, and to correlate pathogenetic periods, aetiological factors and clinical parameters to neuroradiology. The prevalence at the ages 6-15 years was 0.66 per 1000. Postnatally acquired hemiplegia, mainly postinfectious, iatrogenic or posttraumatic, constituted 11%. Among term children with congenital hemiplegia (pre and perinatally derived) the aetiology was considered prenatal, mainly circulatory brain lesions and maldevelopments, in 42%, combined pre and perinatal in 9%, perinatal (cerebral haemorrhage, hypoxia) in 16% and untraceable in 34%. The corresponding distribution among preterm children was 29%, 47%, 25% and 6%, respectively. The rate of preterm birth among congenital cases was 24%. Birth asphyxia was shown to be a poor indicator of pathogenetic period, whereas a cascade of postpartum complications suggested perinatal brain damage. Clinical follow-up of 152 children revealed that 50% had mild, 31% moderate and 19% severe motor dysfunction. Stereognostic sense was impaired in 44% of the children (astereognosia in 20%). Additional impairments (mental retardation, epilepsy, impaired vision, hearing and speech, severe behavioural/perceptual problems) were present in 42%. Term children with congenital hemiplegia tended to be more severely affected than preterm children. The resulting total handicap was considered mild in 40%, moderate in 44% and severe in 16%. The prevalence of severe total handicap was highest among postnatal cases. Computerised tomography (CT), performed in 109 congenital cases, was normal in 26%, showed unilateral ventricular enlargement in 36% and revealed cortical/subcortical cavities in 20%. In the remaining 18% CT findings were classified as "other". With the classification so far used, correlations between CT findings and aetiologies were unsatisfactory and disappointing. In contrast, CT findings showed a strong correlation with clinical degree of severity and magnitude of associated handicap. As a rule, normal CT implied mild disability and unilateral ventricular enlargement moderate, whereas cortical/subcortical cavities were frequently associated with severe handicap, including mental retardation and epilepsy.

A neurological study of hand function of hemiplegic children

Twenty-five children with hemiplegic cerebral palsy between the ages of five and 15 years were examined in more detail, using a torque generator motor. A significant reduction in distal power, fatiguability and speed of movement was found on the hemiplegic side. Proximal power was relatively well preserved. Muscle tone, as would be expected, was significantly increased on the affected side and this was demonstrated by a significant rise in measured resonant frequency. Phasic spasticity in response to stretch was found on EMG to be much more common than phasic and tonic combined. Hand function correlated well with the loss of distal power and speed of movement. There was wide individual variation in the relationship between increased muscle tone and hand function. Thixotropy was normal in spastic muscles. Use of the unaffected hand had a marked effect on muscle tone and EMG of the affected side.

Porencephaly and schizencephaly in adopted infants. Frequency ascertainment in a risk group

A formal inquiry on the health state of 1206 legally adopted children from Indonesia revealed cerebral palsy in 9 (0.9% of 1029 responses obtained), including two who had died. CT examination performed in 7 cases was abnormal in all. Four types of lesions were seen: 1. Bilateral full thickness porencephalies (BFTP lesion) in 4 cases, amounting to 0.4% of the total population on which response was obtained. 2. Full thickness porencephaly of the area of one internal carotid artery in 1 case. 3. Schizencephaly-like lesion in 1 case, confirmed by magnetic resonance imaging. 4. Supratentorial midline cyst resulting in hydrocephalus. The frequency of the BFTP lesion found in 4 out of 7 cerebral palsied investigated by CT is remarkable in view of its rarity in radiological studies on cerebral palsy and because of its relationship to prenatal rather than perinatal damage according to previous pathological studies. This is the first systematic study on the neurodevelopmental outcome of a group of adopted babies which indicates an increased risk to specific prenatal brain damage.

Temporal evolution of hypoxic-ischaemic brain lesions in asphyxiated full-term newborns as assessed by computerized tomography

Hypoxic-ischaemic brain lesions may be detected as low density (LD) areas by means of computerized tomography (CT), but the clinical significance of such LD areas has been controversial. Since timing might be a critical factor, we studied the temporal evolution of LD areas in 9 asphyxiated term babies who had had two or more CT, and compared the changes to the neurodevelopmental outcome. Scans were classified according to the elapsed time after asphyxia as early (day 1-7, n = 6), intermediate (week 2-4, n = 7; week 4-7, n = 3) and late CT (3 months or more, n = 7). In early scans, no, or only ill defined, LD areas were seen in the periventricular region. In intermediate CT's, LD-zones were further diminished in those babies who later were normal. Sharply accentuated LD areas, however, appeared in those who later suffered from neurodevelopmental disorders. These LD areas, probably representing hypoxic-ischaemic lesions, were located periventricularly, extending into the subcortical white matter and the cortex, and usually involved both hemispheres symmetrically. They began to disappear at 4 to 7 weeks in some regions, possibly because of glial proliferation. LD persisting more than 4-7 weeks tended to transform into cyst-like lesions, or marked atrophy. We conclude (1) that hypoxic-ischaemic lesions appear as zones of low density on CT scans performed after the first week and (2) that the extent of such lesions can best be assessed between 9 to 23 days after asphyxia.

Early physiotherapy in the treatment of spastic diplegia

This study reports the effect of early physiotherapy, using Vojta's method, on children with spastic diplegia. Eight children with spastic diplegia (in spite of early treatment which was started before nine months of age) were compared with 21 children with spastic diplegia in which treatment was started between nine months and three years of age. The average age of starting to walk was eight months earlier in the group treated early, although they had more severe complications. They tended to walk steadily with a gait pattern which was quite different from the classical pattern. All of the early treated patients had confirmed organic brain damage with abnormal CT scan or microcephaly. In conclusion, Vojta's method of treatment is one system which improves the prognosis for walking if performed early.

Computed tomography in spastic cerebral palsy

Eighty-three children with spastic cerebral palsy (CP) were examined with cranial CT. In 56 cases the CT findings were abnormal. The most frequent abnormality was atrophy, present in 44 patients. The frequency of pathologic CT increased with severity of the CP. Patients with CP of postnatal aetiology more often had abnormal CT than patients with other known causes. Pathologic CT findings were seen more often in patients with seizures than in patients without. Infarctions and hemiatrophy were much more frequent in patients with hemiplegia than in patients with other types of spastic CP. A special kind of central atrophy, called isolated atrophy around in the cella media, is described. This condition was seen in 20% of cases, most often in hemi- and paraplegic patients. Early infarctions in the border areas between the vascular territories of the internal carotid and the posterior cerebral artery may be the reason for this kind of atrophy.

Developmental neuropsychiatry: concepts, issues and prospects

The empirical findings on the cognitive and behavioral sequelae of head injury in childhood are integrated with others in the literature in order to consider some of the outstanding issues and dilemmas that remain in the field of developmental neuropsychiatry. Particular attention is paid to the apparent nonspecificity of the cognitive sequelae of localized brain lesions in childhood, possible specificities in brain-behavior relationships, the probable importance of age effects in altering the impact of brain lesions, and the threshold above which brain injury may have persistent psychological sequelae.