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Abnormal space occupying lesion within left mastoid and adjacent part of left temporal bone expending it and protruding within the left middle fossa posteriorly as well as within posterior fossa and causing mass effect upon cerebellum, left sigmoid venous sinus and left temporal lobe.

It showed mixed signal intensity with moderate heterogeneous enhancement mainly in peripheries and likely increase in delayed images.

The right lateral and sigmoid venous sinuses are dominant.

The rest of venous sinuses are dilated. Moderate collateral venous circulation is seen.