What are the causes of lobar intracerebral hemorrhage (ICH)?

From the Guidelines

Lobar intracerebral hemorrhage (ICH) is primarily caused by cerebral amyloid angiopathy (CAA) and hypertension.

Causes of Lobar ICH

• Cerebral Amyloid Angiopathy (CAA): CAA is a common age-related pathology characterized by the deposition of β-amyloid peptide in the walls of arterioles and capillaries in the leptomeninges, cerebral cortex, and cerebellar hemispheres (lobar territories) 1.
• Hypertension: Hypertension is a major risk factor for lobar ICH, particularly in patients with a history of high blood pressure 1.
• Other causes: Other potential causes of lobar ICH include arteriovenous malformations, tumors, moyamoya, and cerebral vein thrombosis, which can be identified using imaging modalities such as MRI, MRA, and CTA 1.

Risk Factors

• Age: Older age is a significant risk factor for lobar ICH, with the majority of cases occurring in individuals over 65 years old 1.
• Apolipoprotein E genotypes: Carriers of the apolipoprotein E ε2 or ε4 alleles are at higher risk for lobar ICH 1.
• History of ischemic stroke: A history of ischemic stroke, particularly of the small-vessel "lacunar" type, may also be a predictor of lobar ICH recurrence 1.

From the Research

Causes of Lobar Intracerebral Hemorrhage (ICH)

The causes of lobar intracerebral hemorrhage (ICH) can be varied and complex. Some of the underlying causes include:

• Hypertension: Chronic hypertension is a major cause of ICH, particularly in deep-seated hemorrhages 2, 3, 4
• Vascular abnormalities: Such as amyloid angiopathy, aneurysms, arteriovenous malformation, and cerebral venous thrombosis 2, 3, 5
• Use of anticoagulants: Can increase the risk of ICH 2
• Liver cirrhosis and thrombasthenia: Can also contribute to the development of ICH 2
• Cerebral amyloid angiopathy-related inflammation: A subgroup of cerebral amyloid angiopathy that can present with lobar ICH, encephalopathy, and seizures 6
• Tumor-related ICH: Can occur in patients with brain tumors 5
• Infectious pathologies: Such as brain infections can also cause ICH 5
• Sympathomimetic drug use: Can increase the risk of ICH 3, 4

Location and Age-Related Causes

The location and age of the patient can also play a role in determining the cause of ICH. For example:

• Lobar ICH is more commonly associated with cerebral amyloid angiopathy and less likely associated with hypertension 2, 6
• Younger patients with ICH are more likely to have vascular malformations as the underlying cause 3
• Older patients with ICH are more likely to have hypertension as the underlying cause 3

Diagnostic Workup

A thorough diagnostic workup is essential to identify the underlying cause of lobar ICH. This can include:

• Histopathological examination: To identify underlying vascular abnormalities or other causes of ICH 5
• Radiological studies: Such as MRI or CT scans to visualize the hemorrhage and identify potential causes 2, 5
• Laboratory tests: To rule out underlying conditions such as coagulopathy or infection 5