A non-contrast head CT was obtained as part of the work-up for a person who is unconscious with an unknown etiology. The non-contrast head CT is the study of choice to evaluate for acute intracranial hemorrhage. In this case, an extensive intracerebral hemorrhage was identified. The central location accounts for the limited midline shift despite the extent of the hemorrhage. Increased intracranial pressure has caused herniation, evidenced by obliteration of the basilar cisterns which would normally be seen as thin open spaces around the brainstem in images 8-9.

The patient's history suggests the possibility of hypertensive hemorrhage but its extent and heterogenous appearance make it atypical for a hypertensive hemorrhage. The presence of more than one foci of hemorrhage is suspicious since hypertensive hemorrhages tend to be solitary. The heterogeneity likely represents a mix of clotted and unclotted blood as might be seen when active bleeding is taking place into an area where bleeding has occurred previously. The edema surrounding the hemorrhage suggests this is a process that has been underway for some time. These features increase the likelihood this may be a hemorrhage into a tumor.

The most common cause of intracranial hemorrhage is trauma. Nontraumatic causes include hypertension, aneurysms, amyloid angiopathy, vascular malformations, tumors, over-anticoagulation, and hemorrhage into a prior cerebral infarct.. Hemorrhages are most often associated with chronic poorly controlled hypertension. Chronic hypertension causes structural changes in small arteries that make them susceptible to rupture and hemorrhage. In the brain, the most easily damaged vessels are the penetrating small vessels that perfuse the deep gray matter. Hypertensive hemorrhages occur most often in the putamen/external capsule (40%), lobar white matter of the cerebral hemispheres (22%), thalamus (15%), pons (8%), cerebellum (8%) and caudate (7%)2.

Hypertensive hemorrhages appear on CT as areas of high density with sharply defined borders. There is typically only a single lesion that tamponades itself thus limiting its size. These areas tend to be homogenous unless there is active bleeding or a coagulopathy as would be seen in a hemorrhage associated with anticoagulant use. Edema develops over the course of days following the initial bleed causing an area of low attenuation to develop around the perimeter of the hemorrhage. Hemorrhages frequently extend into the ventricular system but subarachnoid hemorrhage is rare. While an extensive bleed near the base of the brain may suggest a ruptured aneurysm, it is rare for aneurysms to bleed only into the brain without an accompanying hemorrhage near the surface of the brain.
The prognosis is affected by the volume of the hemorrhage, age, admission Glasgow Coma Scale score and blood pressure. Hemorrhages that are deep and located towards the midline, as in this patient, are typically associated with a high mortality rate due to herniation and mass effect. The presence of herniation and the patient's GCS of 2T (Eyes 1, Motor 1, no verbal possible due to ET tube) predict survival is very unlikely.