Early diagnosis and early intervention in cerebral palsy

Abstract

This paper reviews the opportunities and challenges for early diagnosis and early intervention in cerebral palsy (CP). CP describes a group of disorders of the development of movement and posture, causing activity limitation that is attributed to disturbances that occurred in the fetal or infant brain. Therefore, the paper starts with a summary of relevant information from developmental neuroscience. Most lesions underlying CP occur in the second half of gestation, when developmental activity in the brain reaches its summit. Variations in timing of the damage not only result in different lesions but also in different neuroplastic reactions and different associated neuropathologies. This turns CP into a heterogeneous entity. This may mean that the best early diagnostics and the best intervention methods may differ for various subgroups of children with CP. Next, the paper addresses possibilities for early diagnosis. It discusses the predictive value of neuromotor and neurological exams, neuroimaging techniques, and neurophysiological assessments. Prediction is best when complementary techniques are used in longitudinal series. Possibilities for early prediction of CP differ for infants admitted to neonatal intensive care and other infants. In the former group, best prediction is achieved with the combination of neuroimaging and the assessment of general movements, in the latter group, best prediction is based on carefully documented milestones and neurological assessment. The last part reviews early intervention in infants developing CP. Most knowledge on early intervention is based on studies in high-risk infants without CP. In these infants, early intervention programs promote cognitive development until preschool age; motor development profits less. The few studies on early intervention in infants developing CP suggest that programs that stimulate all aspects of infant development by means of family coaching are most promising. More research is urgently needed.

Keywords: cerebral palsy; early diagnosis; early intervention; general movements assessment; neuroplasticity.

Figure 1

Cross-section through the cortex of a fetus of 24 PMA. The following layers can be distinguished, from the inside (bottom) to the outer surface (top): vz, the ventricular zone, which produces neurons; svz, the subventricular zone, which possibly is phylogenetically younger than the ventricular zone, and which produces neurons and glial cells (14); iz, the intermediate zone, i.e., the future white matter; sp, the subplate, which at this stage is very thick and harbors the transient fetal circuitry; cp, the cortical plate; mz, the marginal zone. Ingrowing afferents come from the basal forebrain (bf), thalamus (th), and monoaminergic brain stem nuclei (tegm ma). Figure by curtsy of Dr. Ivica Kostovic, University of Zagreb.

Figure 2

Schematic representation of the two proliferative zones in the cerebellum around 14 weeks PMA, the dorsomedial ventricular zone (VZ), and the dorsolateral rhombic lip (RL). The VZ gives rise to the interneurons of the deep cerebellar nuclei, such as the dentate (De) and to Purkinje cells (PC). Migration occurs radially. The RL has two portions divided by the choroid plexus (cpl) of the 4th ventricle (4V). The upper portion gives rise to the granule precursor cells (EGC) of the external granular layer (EGL) – the cells initially migrate tangentially over the surface of the cerebellum. The tangential migration is later followed by an inward migration to the internal granular layer. The lower portion of the RL gives rise to neurons in the pons, including those of the inferior olive (OL). The arrows indicate the directions of migration. With permission from Dr. Joseph Volpe (31).

Figure 3

Schematic representations of the reorganization of motor and sensory function after a unilateral lesion of the brain at early age. (A) Reorganization after a “preterm” unilateral lesion. The lesion involves the periventricular white matter. The reorganization includes (a) the persistence of ipsilateral corticospinal projections to the paretic hand originating in the contralesional hemisphere and (b) axonal plasticity of the thalamocortical afferents bypassing the lesion in the ipsi-lesional hemisphere. (B) Reorganization after a “term” unilateral lesion, which usually does not include the periventricular white matter. Motor and sensory functions of the paretic hand are organized in the lesioned hemisphere.