An intra-parenchymal fluid collection with relatively uniform strong diffusion restriction and thin peripheral enhancement is a characteristic appearance for a cerebral abscess; a key feature, in this case, is appreciating the close relationship with the base of skull mass and the likely close association between the mass and the abscess which may make definitive surgical intervention difficult. The other key observation is appreciating the subdural collection and the fact this collection also restricts diffusion in keeping with a subdural abscess (subdural empyema).

The patient initially had the abscess drained, which grew small numbers of Streptococcus intermedius. The subdural collection was too small for neurosurgical intervention initially but subsequent imaging showed enlargement of the subdural collection which was subsequently washed out by neurosurgery, following which inflammatory markers normalized.