C. M. Grosse1, C. Schell-Apacik2, I. Körte1, L. Eftimov1, M. F. Reiser1, B. B. Ertl-Wagner1; 1Munich/DE, 2Berlin/DE
Children with CMTC present a mild developmental delay and very seldom seizures.
Structural brain anomalies commonly found in theses children are:
- ventriculomegaly including obstructive and non-obstructive hydrocephalus
- tonsillar herniation.
- cortical dysplasia
- cerebral or ventricular asymmetry
- signal abnormalities of the white matter
- enlarged intracranial veins and venous sinuses
- dilated Virchow-Robin spaces
- thick corpus callosum
- cavum pellucidum et vergae
- optic nerve enlargement
A constellation of characteristic features was found in all three children:
- White matter lesions in the deep white matter especially in the terminal zone in combination with an adequate myelinisation of the subcortical areas
- A pseudo-Chiari constellation with herniation of the cerebellar tonsills
- Focal polymicrogyria in several areas of the cortex
- Dilation of the ventricles
- Dilation of the sagital sinus
The pseudo-Chiari constellation was not present at the age of 6 weeks, but developed later at the age of 22 months in the child with a repeat MR exam.
Some authors believe that tonsillar herniation is a secondary effect due to the megalenchelaphy and the increased pressure in the posterior fossa and not a real anomaly. Our observation would sustain this thesis.
The hydrocephalus is supposed to be a combination of more factors, one of them being the rapidly enlarging cerebellum.