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What is In cerebral angiography, the dye is injected through – and explain in detail?
On MRI, diagnostic confusion occasionally arises between arachnoid cysts and epidermoid cysts. The two masses may have similar characteristics on T1-weighted and T2-weighted images, and neither shows enhancement with gadolinium.
However, arachnoid cysts follow CSF signals on all sequences, in particular on FLAIR sequence, in contradistinction to epidermoid cyst.
Diffusion-weighted images (DWIs) allow easier differentiation of the two masses.