Case Discussion

The main causes of primary intracerebral haemorrhage are cerebral amyloid angiopathy and hypertensive small vessel disease. Cerebral amyloid mainly affects the cortical and leptomeningeal vessels hence causes lobar bleeds and cortical superficial siderosis, whereas hypertensive small vessel disease mainly affects the deep perforating arterioles hence causes deep haemorrhage. 

Patients with intracerebral haemorrhage/microbleeds in both lobar and deep hemispheric brain regions (mixed intracerebral haemorrhage) are commonly encountered in clinical practice.

Previous studies suggest that hypertensive small vessel disease could cause lobar microbleeds. The pathologic process underlying mixed intracerebral haemorrhage may be a severe vasculopathy -similar to hypertensive microangiopathy- caused by risk factors such as hypertension and diabetes mellitus, or more of a combination of both CAA and HTN-SVD, but this issue is unresolved at that time.

In a study ¹, patients with mixed intracerebral haemorrhage seemed to have a more pronounced classic vascular risk factor burden (more lacunes, higher creatinine) than patients with cerebral amyloid but a vascular risk factor profile similar to those with hypertensive microangiopathy, whereas compared to patients with hypertensive microangiopathy, those with mixed ICH were older with more lacunes and microbleeds.