Hemorrhagic Stroke | What Happens When a Blood Vessel Bursts in Your Brain?

An intracerebral hemorrhage is a type of stroke that occurs when a blood vessel within the brain tissue itself ruptures and bleeds. This leakage of blood creates a hematoma, which is a localized collection of blood that puts pressure on the surrounding brain tissue, damaging brain cells. The primary cause of this type of stroke is chronic high blood pressure, also known as hypertension, which weakens the artery walls over time, making them susceptible to bursting. Other less common causes include arteriovenous malformations (AVMs), which are abnormal tangles of blood vessels, head trauma, or the use of blood-thinning medication. The sudden increase in pressure inside the skull can rapidly lead to neurological deficits, with symptoms directly related to the location and size of the bleed. For instance, a hemorrhage in the cerebellum, which controls coordination, will manifest as problems with balance and movement.

A subarachnoid hemorrhage involves bleeding into the subarachnoid space—the area between the brain and the thin tissues that cover it, called meninges. Unlike an intracerebral hemorrhage, this bleeding occurs on the surface of the brain, not within it. The most common cause is the rupture of a cerebral aneurysm, which is a balloon-like bulge or weak spot on an artery wall. When it bursts, blood spreads over the surface of the brain and mixes with the cerebrospinal fluid. Patients often describe the primary symptom as a sudden, extremely severe headache, often called a "thunderclap headache," which is unlike any headache experienced before. This condition is a medical emergency because the blood can cause a rapid increase in intracranial pressure and also lead to vasospasm, where blood vessels in the brain narrow, restricting blood flow and causing further brain damage.

The initial symptoms of a hemorrhagic stroke are sudden and severe. The most characteristic sign is a "thunderclap headache," especially in cases of subarachnoid hemorrhage. Other common symptoms include sudden nausea and vomiting, visual disturbances such as blurred or double vision, and a stiff neck. Individuals may also experience a rapid onset of numbness, weakness, or paralysis, typically on one side of the body. Confusion, dizziness, loss of balance, or difficulty speaking and understanding speech are also key indicators. Seizures can occur as well. The specific symptoms depend entirely on which part of the brain is affected by the bleeding.

Immediate diagnosis is critical. The primary tool used is a non-contrast computed tomography (CT) scan of the head, which can quickly detect bleeding in or around the brain. A magnetic resonance imaging (MRI) scan may also be used to get a more detailed view of the brain tissue. Once confirmed, treatment focuses on controlling the bleeding, removing the blood collection if necessary, and relieving pressure on the brain. This includes managing blood pressure, discontinuing any anti-clotting medications, and administering drugs to reduce swelling. In some cases, surgical intervention is required to either clip a ruptured aneurysm or remove a large hematoma.

While not all hemorrhagic strokes are preventable, managing key risk factors significantly reduces the likelihood of their occurrence. The single most important preventative measure is controlling high blood pressure (hypertension) through medication, diet, and exercise. It is essential to avoid smoking and limit alcohol consumption, as both contribute to hypertension and can weaken blood vessels. For individuals with a known aneurysm or arteriovenous malformation (AVM), medical procedures can sometimes be performed to secure the abnormality before it has a chance to rupture. Regular medical check-ups are vital for monitoring blood pressure and other vascular risk factors, especially for those with a family history of strokes or aneurysms.