We report on a 3.8-year-old girl who was born preterm at 26 weeks of gestation. Due
to a posthemorrhagic hydrocephalus she has a ventriculoperitoneal shunt since the
age of five months. Clinically she presents with a left-sided spastic hemiparesis.
On day of admission she was found unresponsive in a febrile state. After buccal application
of midazolam she regained consciousness. On magenitic resonance imaging (MRI) with
diffusion weight sequences (DWI) areas of increased signal intensities throughout
the right cerebral hemisphere with reduced values for the apparent diffusion coefficient
(ADC) were seen. There were no epileptic discharges on the electroencephalogramm.
After two days the patient deteriorated again. On MRI signs of increased intracranial
pressure were seen and an extraventricular drainage was applied. Additionally high
signal intensity of the whole right hemisphere and the left cerebellar hemisphere
with corresponding lower ADC values were seen. This lead to the diagnosis of a crossed
cerebellar diaschisis (CCD), most likely resulting from prolonged seizure activity.
Anticonvulsive medication with levetiracetam was started and the patient recovered.
After 4 weeks the MRI showed atrophy of the right hemisphere and progressive parenchymal
atrophy of the left cerebellum.
The pathophysiological mechanisms of CCD in SE are not entirely understood yet. Excessive
cortical excitatory input through the cortico-ponto-cerebellar pathway might lead
to a decline of purkinje cells and finally to neuronal necrosis in the contralateral
cerebellar hemisphere. Alternatively the excitatory input might be reduced by the
cortical cytotoxic edema in SE leading to a decrease in neuronal cell activity in
the contralateral cerebellar hemisphere. This deactivation could cause a decrease
in cerebellar perfusion and reduction in metabolism.
MRI-techniques with DWI are a useful tool to identify CCD in SE at an early stage.
Anticonvulsive treatment should be started or expanded as soon as possible to avoid
further neuronal damage.
