A brain aneurysm is a bulge or ballooning in a blood vessel in the brain.
It happens when a weak spot in the blood vessel wall balloons out and fills with blood.
Most brain aneurysms don’t cause symptoms until they rupture, leading to a subarachnoid hemorrhage—a life-threatening type of stroke.
When unruptured, it may cause headaches, vision problems, or pain behind the eyes if it's pressing on nerves.
An Arteriovenous Malformation (AVM) is a tangled connection of arteries and veins in the brain that bypasses normal brain tissue and disrupts blood flow.
They may cause headaches, seizures, or neurological symptoms, and like aneurysms, can rupture and bleed, causing a stroke.
– Often the first test if rupture is suspected. – Can detect bleeding in the brain.