Over time, subdural hygromas may become membrane bound 8 and as in Patient 4 (Figure 1a), the hygromas may produce mass effect on the cerebral hemispheres requiring surgical decompression.

The cranial magnetic resonance imaging showed the presence of a large arachnoid cyst in the posterior fossa and bilateral supratentorial subdural cystic hygromas as well as small arachnoid cysts.

In this case, the bleeding was from a left middle cerebral artery aneurysm. Also note the prominent frontal subdural fluid collections bilaterally. These fluid collections are most likely subdural ...

Dr. Pamela W. Schaefer: Magnetic resonance imaging (MRI) of the head revealed a 12-mm right subdural hygroma with a midline shift of 10 mm, a right cerebellar cavernous malformation, and numerous ...