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T1 post-gadolinium acquisition demonstrates a large enhancing mass with surrounding oedema in the right hemisphere, causing compression of the lateral ventricle and herniation of brain tissue over the tentorium causing compression of the mesencephalon (arrows).

Due to the mass effect of the tumour, the medial part (uncus) of the right temporal lobe (arrow) is herniating over the edge of the tentorium (*) and thereby compressing the mesencephalon against the free edge of the contralateral tentorium and causing a notch on the left side.