Causes of spontaneous intracranial hemorrhage

The causes of spontaneous intracerebral hemorrhage are sometimes, but not always, different from those of TIA and ischemic stroke. Spontaneous intracranial hemorrhage may be classified as  

Primary intracerebral hemorrhage is more common than subarachnoid hemorrhage, and its incidence increases with age (see Fig. 1.1). It is more frequent in Southeast Asian, Japanese and Chinese populations than in whites. The most common causes are intracranial small vessel disease, which is associated with hypertension, cerebral amyloid angiopathy and intracranial vascular malformations (Sutherland and Auer 2006). Rarer causes include saccular aneurysms, hemostatic defects, particularly those induced by anticoagulation or therapeutic thrombolysis, antiplatelet drugs, infective endocarditis, cerebral vasculitis and recreational drug use (Neiman et al. 2000 O Connor et al. 2005). 

The site of primary intracerebral hemorrhage provides information as to the cause hypertensive hemorrhages (Fig. 7.1a) tend to occur in the basal ganglia, thalamus, and pons, while lobar hemorrhages are more often caused by cerebral amyloid angiopathy, vascular malformations and hemostatic failure (Dickinson 2001 Smith and Eichler 2006 Sutherland and Auer 2006) (Table 7.1) (Fig. 7.1b). Multiple hemorrhages suggest certain specific causes  

Hemorrhagic transformation of cerebral infarction, venous more often than arterial Intracranial venous thrombosis (Ch. 29) 

Infections infective endocarditis, herpes simplex, leptospirosis, anthrax Sickle cell disease Moyamoya syndrome (Ch. 6) 

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Dissection of the internal carotid and vertebral arteries is a common cause of stroke, particularly in young patients. Although many occur due to trauma, it is estimated that over half occur spontaneously. The mechanism of stroke following arterial dissection is either by artery-to-artery embolism, by thrombosis in situ, or by dissection-induced lumenal stenosis with secondary cerebral hypoperfusion and low-flow watershed infarction. Occasionally, dissection may lead to the formation of a pseudoaneurysm as a source of thrombus formation. Vertebrobasilar dissections that extend intracranially have a higher risk of rupture leading to subarachnoid hemorrhage (SAH). ° ... 

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