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Hemorrhagic strokes are frequently caused by the bursting of an aneurysm (an abnormal bulging of a blood vessel in the brain) or an arteriovenous malformation (AVM), a cluster of abnormal blood vessels.
In the case of an aneurysm, the weak spot in the vessel wall can be stretched out over the years, often by high blood pressure, which ultimately causes it to rupture.
While aneurysms may not cause any symptoms until they burst (sometimes causing people to liken them to "time bombs" in the brain), AVMs may have many associated symptoms, including seizures, progressive neurologic problems and severe headaches that are unresponsive even to strong medications.
Until recently, some aneurysms and AVMs were virtually impossible to treat without high risk to the patient. New diagnostic and surgical advances pioneered at the Stanford Stroke Center have made it possible to treat these important causes of stroke and offer patients the likelihood of a cure.
Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.
Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.