What can cause a cerebral aneurysm and how are they classified?
A cerebral aneurysm is a weak or thin spot on a blood vessel in the brain that balloons out and fills with blood. The bulging aneurysm can put pressure on a nerve or surrounding brain tissue. It may also leak or rupture, spilling blood into the surrounding tissue (called a hemorrhage). Cerebral aneurysms can be congenital, resulting from an inborn abnormality in an artery wall. They are also more common in people with certain genetic diseases, such as connective tissue disorders and polycystic kidney disease, and certain circulatory disorders, such as arteriovenous malformations (snarled tangles of arteries and veins in the brain that disrupt blood flow). Other causes include trauma or injury to the head, high blood pressure, infection, tumors, artherosclerosis (a blood vessel disease in which fats build up on the inside of artery walls) and other diseases of the vascular system, cigarette smoking, and drug abuse.
There are three types of cerebral aneurysm.
Saccular aneurysm-is a rounded or pouch-like sac of blood that is attached by a neck or stem to an artery or a branch of a blood vessel. This type is also known as a berry aneurysm because it resembles a berry hanging from a vine. This is the most common form of cerebral aneurysm and is typically found on arteries at the base of the brain. It is most common in adults.
Lateral aneurysm-appears as a bulge on one wall of the blood vessel.
Fusiform aneurysm-is formed by the widening along walls of the vessel.