Left frontal lobar hemorrhage with involvement of the cortex and extension into the subarachnoid space. Background changes of multiple old lobar hemorrhages and cortical superficial siderosis. Mild small vessel disease (enlarged perivascular spaces and white matter hyperintensities) and atrophy. Multiple recurrent lobar hemorrhages with subarachnoid hemorrhage.

Lobar intracerebral hemorrhage is frequently attributed to small vessel diseases (cerebral amyloid angiopathy or arteriolosclerosis).  Differentiating lobar hemorrhage due to cerebral amyloid angiopathy and arteriolosclerosis is important due to differences in recurrent ICH and post-stroke dementia risk (higher with CAA-associated ICH).

The initial CT shows subarachnoid hemorrhage but no finger-like projections from the hematoma. The patient possessed at least one APOE e4 allele. Therefore they are high risk for CAA-associated ICH on the Edinburgh CT and genetic diagnostic criteria for lobar intracerebral hemorrhage associated with cerebral amyloid angiopathy.

This patient has a multiple lobar macrohaemorrhages and cortical superficial siderosis and so is probable CAA on the modified Boston criteria.

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PATHOLOGY: Post mortem showed multiple intracerebral hemorrhages of different ages with subarachnoid hemorrhage.  Multiple microbleeds are present. The vessels in the leptomeninges and cortex show extensive cerebral amyloid angiopathy along with capillary amyloid deposition. Parenchymal amyloid deposition is present but not as prominent as would be expected for the degree of vascular amyloid.