Thursday 29 September 2011


A 9 y o boy  with history of seizures. 
Here are his Non contrast CT, MRI Axial FLAIR, T1 and T2w images of Brain. 

There are multiple indentations in the wall of lateral ventricles due to sub ependymal nodules with density same as that of cortical gray matter on CT and signal intensity on MRI.

Imaging diagnosis : Nodular variety of multifocal heterotrophic gray matter. 


A congenital disorder of abnormal neuronal migration.
Gray matter stuck at wrong place.

Can be inherited or acquired (from maternal trauma, infection or toxin)

Normally sub ependymal germinal zone proliferates and form neuroblasts and glial cells which then migrates outwards towards cerebral convexity forming an outer cortical grey matter and inner white matter. Any interruption or arrest in the normal course of this neuronal migration leaves heterotrophic neuronal deposits. These being gray matter deposits follow same density and signal intensity as that of cortical gray matter, non enhancing.

Sub ependymal nodular heterotrophia – a focal or multi focal subependymal nodules.
Band heterotrophia – alternate band of gray and white matter , ‘ double cortex’.

Clinical presentation : 
Seizures is most common, delayed milestones.

Closest differential is subependymal nodules of Tuberous sclerosis which often shows an associated calcification. 

Surgery reserved for intractable Sz.
Resect small accessible epileptogenic nodules.
Corpus callosotomy if bilateral or diffuse unresectable lesions.

No comments: