Presentation
Fall from roof. IVDU.
Patient Data
A large parenchymal hematoma in the inferior aspect of the right frontal lobe and the superior aspect of the right temporal lobe is present with intraventricular extension and contralateral hydrocephalus. Additionally there is subarachnoid blood in the right sylvian cistern and in the right side of the suprasellar cistern and in the right cerebral sulci. The mass exerts marked mass effect with right uncal herniation and 16 mm right-to-left midline shift and subfalcine herniation.
At the anterior most extent of the hematoma is a rounded lower density component, suspicious for an aneurysm.
There is 12 mm transverse x 11 mm craniocaudal x 8.5 millimeter AP inferolaterally directed right MCA bifurcation aneurysm.
There is no other aneurysm or severe steno-occlusive lesion in the major intracranial arteries. There is conventional branching anatomy of the great vessels from the aortic arch.
Case Discussion
It is critical to remember that not all aneurysms result in predominantly subarachnoid hemorrhage, but that in some instances (particularly MCA and Acom aneurysms) rupture will be predominantly intraparenchymal.
In this instance (IVDU) the possibility of a mycotic aneurysm needs to be entertained.