*21-month-old girl presented with seizure.




What is the most likely diagnosis?
1. Subependymal giant cell astrocytoma
2. Subependymal grey matter heterotopia
3. Tuberous sclerosis
4. Subependymal haemorrhage
Answer
Answer: Subependymal grey matter heterotopia
Case Discussion:
MR images show masses which projects into the posterior of the bilateral lateral ventricle. It has signal intensity which match those of cortex on all sequences.

This is the most common form of grey matter heterotopia. Subependymal grey matter heterotopia can be divided according to morphology into:
-unilateral focal
-bilateral focal
-bilateral diffuse: a band of grey matter surrounding the ventricles
Subependymal grey matter heterotopias consist of clusters of neurons and glial cells. They generally are associated with epilepsy and occasionally developmental delay.
References:
1. Abdel Razek AA, Kandell AY, Elsorogy LG et-al. Disorders of cortical formation: MR imaging features. AJNR Am J Neuroradiol. 2009;30 (1): 4-11.doi:10.3174/ajnr.A1223 – Pubmed citation.