Clinical, pathogenetic and neuropathological correlates in dystonic cerebral palsy

Localization of Basal Ganglia and Thalamic Damage in Dyskinetic Cerebral Palsy

BACKGROUND

Dyskinetic cerebral palsy affects 15%-20% of patients with cerebral palsy. Basal ganglia injury is associated with dyskinetic cerebral palsy, but the patterns of injury within the basal ganglia predisposing to dyskinetic cerebral palsy are unknown, making treatment difficult. For example, deep brain stimulation of the globus pallidus interna improves dystonia in only 40% of patients with dyskinetic cerebral palsy. Basal ganglia injury heterogeneity may explain this variability.

METHODS

To investigate this, we conducted a qualitative systematic review of basal ganglia and thalamic damage in dyskinetic cerebral palsy. Reviews and articles primarily addressing genetic or toxic causes of cerebral palsy were excluded yielding 22 studies (304 subjects).

RESULTS

Thirteen studies specified the involved basal ganglia nuclei (subthalamic nucleus, caudate, putamen, globus pallidus, or lentiform nuclei, comprised by the putamen and globus pallidus). Studies investigating the lentiform nuclei (without distinguishing between the putamen and globus pallidus) showed that all subjects (19 of 19) had lentiform nuclei damage. Studies simultaneously but independently investigating the putamen and globus pallidus also showed that all subjects (35 of 35) had lentiform nuclei damage (i.e., putamen or globus pallidus damage); this was followed in frequency by damage to the putamen alone (70 of 101, 69%), the subthalamic nucleus (17 of 25, 68%), the thalamus (88 of 142, 62%), the globus pallidus (7/35, 20%), and the caudate (6 of 47, 13%). Globus pallidus damage was almost always coincident with putaminal damage.

CONCLUSIONS

Noting consistent involvement of the lentiform nuclei in dyskinetic cerebral palsy, these results could suggest two groups of patients with dyskinetic cerebral palsy: those with putamen-predominant damage and those with panlenticular damage involving both the putamen and the globus pallidus. Differentiating between these groups could help predict response to therapies such as deep brain stimulation.

Birth-related syndromes of athetosis and kernicterus

"Athetosis," from the Greek athetos, meaning "without fixed position," is a movement disorder first described by Hammond in 1871. The term described slow, irregular continual movements of the distal extremities. In 1983, Foley defined the athetoid syndrome as "a nonprogressive but evolving disorder due to damage to the basal ganglia of the full-term brain … [with] impairment of postural reflexes, arrhythmical involuntary movements, and dysarthria, [but] sparing … sensation, ocular movements and … intelligence." A decade later, "athetoid syndrome" was replaced by "dyskinetic cerebral palsy." Injury to basal ganglia by various mechanisms, including asphyxia, trauma, perinatal strokes, and kernicterus, is known to cause birth-related athetosis. Kernicterus originally described the neuropathology of bilirubin-induced brain injury, where the deep nuclei of the brain stain yellow. Kernicterus now describes the clinical features of chronic bilirubin encephalopathy, which include an extrapyramidal movement disorder, sensorineural hearing loss, impaired upward gaze, and dental enamel dysplasia. Aggressive treatment of perinatal hyperbilirubinemia has led to a decline in kernicterus so that, today, it is a rare cause of dyskinetic cerebral palsy. In this chapter, we provide a historic overview of athetosis and its formerly common cause, kernicterus. We relate earlier terminology to more recent definitions of impairments in dyskinetic cerebral palsy, including dystonia, chorea, and choreoathetosis.

Clinical outcome after near-fatal late shunt complication in hydrocephalus

Shunt revision is inevitable in most shunted hydrocephalic children but the revisions rarely affect the prognosis markedly. This report presents the case of an otherwise healthy boy who, after an uneventful gestation and birth, manifested hydrocephalus in the neonatal period and was shunted at the age of 3 months. His subsequent development and school performance were normal until the age of 10 years, when he developed his first episode of shunt dysfunction. During the emergency shunt revision, intraventricular haemorrhage occurred, causing acute neurological symptoms and signs. In the promptly undertaken reoperation external drainage was inserted but accidentally without a functioning air needle. The intracranial pressure (ICP) rose to 40 cm H2O before correction. These incidents were followed by a 4-month period of unstable shunt function (12 reoperations) and deteriorating neurology. When stable shunt function was eventually achieved, he had severe contractures, minimal active motor function and no active speech. During a 2-year period of rehabilitation, he recovered almost normal motor function and normal intellectual function. Memory functions, vigilance and concentration span remained clearly subnormal. He returned to normal school and his performance is average. It is concluded that the relatively favourable outcome is the probable result of reversible partial herniation and increased ICP.

Dyskinetic cerebral palsy and birth asphyxia

Of 115 children with dyskinetic cerebral palsy (CP) in the Mersey region, 17 were born at term and at an appropriate weight for age, and have preserved cognitive abilities. 10 of these are likely to have sustained intrapartum asphyxial brain-damage as the cause of their CP. In such circumstances, a characteristic pattern is usually seen of severe fetal distress occurring late in labour, severe but short-lived birth asphyxia and only mild or moderate hypoxic-ischaemic encephalopathy. This clinical picture should be distinguished from the pattern of birth asphyxia which precedes the development of spastic quadriplegic CP.

Athetoid cerebral palsy with cysts in the putamen after hypoxic-ischaemic encephalopathy

Three cases of athetoid cerebral palsy after hypoxic-ischaemic encephalopathy (HIE) are reported. All three neonates had haemorrhagic lesions in the basal ganglia and thalami on magnetic resonance imaging (MRI). Prior cranial ultrasound had detected the lesions in only two cases. In all three children athetoid movements began within the first year of life. Follow up MRI scans showed bilateral symmetrical cystic lesions in the posterior putamen. Although haemorrhagic lesions within the basal ganglia are a common MRI finding in neonates with HIE, few of these babies develop athetoid cerebral palsy. We believe this to be the first report of discrete cystic lesions found in the basal ganglia of children with athetoid cerebral palsy.

Dyskinetic and dystonic cerebral palsy and birth

Two hundred and nineteen cases of the dyskinetic and dystonic forms of cerebral palsy which were seen in the course of three decades at a single clinic have been analysed. Fifty-seven patients had kernicterus. In the remaining 162, 71% of whom were born at term, birthweight was below the expected mean in two-thirds. There was no relationship between birth weight, or abnormal birth, or asphyxia, and the ultimate clinical severity of the children. We conclude that abnormal birth and asphyxia are not direct causes of the cerebral damage, but are expressions of a pre-existing condition resulting in susceptibility to the stress of birth, whether it is normal or abnormal.

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.

Hemiplegic cerebral palsy: correlation between CT morphology and clinical findings

Morphological findings on CT were compared with clinical features of 111 children with hemiplegic cerebral palsy. Periventricular atrophy, interpreted as periventricular leukomalacia, was the most prevalent CT finding, although this type of lesion did not indicate severity of neurological impairment. Maldevelopments were associated with arm-dominated hemiplegia and with a wider range of clinical impairments than previously described. Cortical/subcortical atrophy, less common than presumed, indicated arm-dominated hemiplegia and was associated with more severe impairment than were other CT findings. A normal CT scan indicated leg-dominated hemiplegia and mild impairment. The morphological information obtained by CT was found to be useful for predicting clinical outcome, and was considered an important adjunct to clinical history and findings in these children.

Dyskinetic cerebral palsy. I. Clinical categories, associated neurological abnormalities and incidences

An unselected series of 116 dyskinetic cerebral palsy cases born 1959-70 was delineated and subgrouped according to neurological criteria into 35 hyperkinetic (30%) and 81 dystonic (70%) cases. Of the hyperkinetics, 80% had a mild motor disability, while 90% of the dystonics had moderate or severe disability. Subordinated spastic signs were found in 9% of the hyperkinetic and in 44% of the dystonic cases. IQ was greater than 90 in 69% of the hyperkinetics and 25% of the dystonics and less than 50 in 11% and 41%, respectively. Two or more additional neurological abnormalities (spasticity, mental retardation, epilepsy, anarthria, dysarthria, hearing deficit) were detected in 46% hyperkinetic and 81% dystonic cases. A heavy multihandicap complex was present predominantly in the dystonic subgroup. The 5-19 year mortality rate was 6% and was confined to the most severely handicapped dystonic cases. The twin rate was 5%. A total of 9% had birth weights less than or equal to 1500 g, and 31% had less than or equal to 2500 g. The weight- and age-specific incidences increased rapidly with decreasing birth weights and gestational ages. The crude incidence of hyperkinetic cerebral palsy was 0.07 and dystonic cerebral palsy 0.17 per thousand live births.