Dysembryoplastic Neuroepithelial Tumour

A DNET is a benign intracortical mass, typically multinodular in appearance, with a ‘bubbly appearance’. It coexists within an area of cortical dysplasia, and is characteristically the cause of intractable partial seizures. It demonstrates essentially no growth over time, although very gradual increase in size has been described.
In this T2 weighted image, note the marked increase in signal in the mesial temporal lobe, involving the hippocampus and amygdala, with bubbly foci of CSF intensity within it. This appearance and location is characteristic.
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Reference:
Osborn, A. Diagnostic Imaging - BRAIN. Amirsys
Credit: Dr Frank Gaillard
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