Presentation
Young adult with learning difficulties presents moribund with a fever.
Patient Data
![](https://prod-images-static.radiopaedia.org/images/5274197/fd690ad68a2d9641b948014f6a4b77_thumb.jpg)
![This study is a stack](/packs/stack-YQKLCKBI.gif)
![](https://prod-images-static.radiopaedia.org/images/5274240/60467382fd0be56f881f8c7b2783ef_thumb.jpg)
![This study is a stack](/packs/stack-YQKLCKBI.gif)
![](https://prod-images-static.radiopaedia.org/images/5274197/fd690ad68a2d9641b948014f6a4b77_big_gallery.jpg)
Huge ring enhancing cystic lesion with perilesional edema in the left cerebellar hemisphere, which is displacing and effacing the 4th ventricular with a resultant triventricular hydrocephalus.
The cerebellar tonsils herniate inferiorly due to mass effect.
![](https://prod-images-static.radiopaedia.org/images/5275028/6822cbce7d20da8eef08bcd63e7c72_big_gallery.jpg)
The left mastoid air cell are opacified as is the middle ear with partial destruction of the ossicular chain.
The petrous temporal bone contains a mixture of lucent and sclerotic with destruction of the medial cortex close to the petrous apex.
Case Discussion
An extreme example of two pathologies. A profound mastoiditis with intracranial extension, causing a huge cerebellar abscess, with a resultant hydrocephalus.
The patient went to surgery immediately, with no residual neurological deficit after surgery.