Intracranial hemorrhage

Types and characteristic locations

Intracranial hemorrhages are categorized by where blood collects. Common types include:

• Intracerebral (or intraparenchymal): bleeding into brain tissue itself, often from small vessel rupture.
• Subarachnoid: blood enters the space between the brain and the thin membranes covering it; often linked to aneurysm rupture.
• Subdural: blood gathers between the dura and the brain surface, frequently after trauma.
• Epidural: bleeding between the skull and dura, classically associated with skull fracture and arterial tear.

Causes and risk factors

Bleeding can follow direct injury or arise without obvious trauma. Contributing causes include long-standing high blood pressure, ruptured aneurysms or vascular malformations, disorders of blood clotting, and anticoagulant or antiplatelet medications. Weakness of the blood vessel wall, age-related changes and certain infections or tumors may also play a role. In all cases the immediate source is a breach of the brain's blood vessels.

Signs, diagnosis and acute care

Presenting features vary by size and site of the bleed. Common signs are sudden severe headache, nausea or vomiting, decreasing consciousness, weakness or numbness on one side, difficulty speaking or seeing, and seizures. Rapid evaluation uses brain imaging—non‑contrast CT is the usual first test, with MRI or angiography used for further detail. Initial treatment focuses on airway and circulation support, reducing intracranial pressure, controlling blood pressure, and reversing blood-thinning drugs when necessary.

Treatment options and recovery

Management ranges from observation and medical therapy to neurosurgical interventions. Neurosurgeons may perform clot evacuation, decompression, or place drains to relieve hydrocephalus. Endovascular techniques can secure aneurysms or arteriovenous malformations. Rehabilitation—physical, occupational and speech therapy—is often required during recovery. Outcomes depend heavily on hemorrhage size, location, patient age and underlying health.

Prevention and notable considerations

Preventive measures include effective blood pressure control, careful use and monitoring of anticoagulant medications, and addressing modifiable vascular risks such as smoking and uncontrolled diabetes. Some complications are specific to type: for example, subarachnoid hemorrhage can cause delayed cerebral vasospasm, and subdural bleeds may present late with progressive cognitive change. Prompt recognition and rapid medical care improve chances of survival and functional recovery.