CASE 2: SAH in left ambient cistern
, DSA showing Pcom aneurysm.
A CT scan of the brain showed a small subdural effusion in the frontal and left parietal lobes and a small subarachnoid haemorrhage in the left ambient cistern
14 Most intracranial lipomas occur in the midline in the region of the corpus callosum (45%), the ambient cistern and suprasellar region (23%).
Lipoma of the ambient cistern causing obstructive hydrocephalus.
Almost complete obliteration of the contralateral ambient cistern
was noted in addition to significant (17 mm) shift of the midline structures to the right.
In a study by Giannetti,  CT scan findings such as mediolateral diameter of the lesion, location of the hematoma, status of the ambient cisterns
, and position of the midline structures were used as the criteria to decide which patients benefit from early surgery.