Diagnosis
Multiple classification systems using Magnetic Resonance Imaging (MRI) have been developed, linking brain lesions to time of birth, cerebral palsy subtype and functional ability. The overall goal of these studies is to elucidate etiology, timing of injury and pathogenesis of cerebral palsy.Around 70% of patients with DCP show lesions in the cortical and deep grey matter of the brain, more specifically in the basal ganglia and thalamus. However, other brain lesions and even normal-appearing MRI findings can occur, for example white matter lesions and brain maldevelopments. Patients with pure basal ganglia and thalamus lesions are more likely to show more severe choreoathetosis whereas dystonia may be associated with other brain lesions, such as the cerebellum. These lesions occur mostly during the peri- and postnatal period since these regions have a high vulnerability during the late third trimester of the pregnancy. Unfortunately, contemporary imaging is not sophisticated enough to detect all subtle brain deformities and network disorders in dystonia. Research with more refined imaging techniques including diffusion tensor imaging and functional MRI is required. Prevention
Prevention strategies have been developed for the different risk factors of the specific cerebral palsy subtypes. Primary prevention consists of reducing the possible risk factors. However, when multiple risk factors cluster together, prevention is much more difficult. Secondary preventions may be more appropriate at that time, e.g. prevention of prematurity.
Respectively 12,7% and 49% of the patients were assigned in level IV and V of the Gross Motor Function Classification System (GMFCS). The same trend appeared in manual ability with 21,8% in level IV and 43,6% in level V of the Manual Ability Classification System (MACS). A good correlation between the functional classification scales and the total dystonia level was found, meaning that a higher level of functional disability correlates with a higher dystonia level. The same study showed no associations with choreoathetosis. These results suggest that dystonia typically has a bigger impact on functionality and a larger effect on activity, participation and quality of life than choreoathetosis.As previously mentioned, dystonia predominates in most patients, partly because dystonia is often more noticeable and severe than choreoathetosis. Both increase with activity and are generalized over all body regions with a higher severity in the upper limbs than in the lower limbs. Dystonia has a significantly higher level of severity in the distal parts of the extremities, whereas choreoathetosis is more equally distributed. Causes
Dyskinetic cerebral palsy could have multiple causes. The majority of the children are born at term and experience perinatal adverse events which can be supported by neuroimaging. Possible causes are perinatal hypoxic-ischaemia and neonatal shock in children born at term or near term. Hyperbilirubinaemia used to be a common contributing factor, but is now rare in high-income countries due to preventive actions. Other aetiological factors are growth retardation, brain maldevelopment, intracranial haemorrhage, stroke or cerebral infections.