aneurizma

Aneurizma is a localized dilation of a blood vessel caused by weakening of the vessel wall. It most commonly affects arteries and can occur in the brain, the aorta, or peripheral arteries.

There are true aneurysms and false aneurysms (pseudoaneurysms). True aneurysms involve all layers of the vessel wall and can be fusiform or saccular. False aneurysms occur when a breach in the vessel wall is contained by surrounding tissue, forming a hematoma that communicates with the vessel lumen.

Common causes and risk factors include atherosclerosis, hypertension, smoking, aging, and genetic disorders such as Marfan syndrome or Ehlers-Danlos syndrome. Infections or inflammatory processes can lead to mycotic or inflammatory aneurysms.

Symptoms vary; many aneurysms are asymptomatic until enlargement or rupture. Intracranial aneurysms may present with sudden severe headache and neck stiffness; abdominal aortic aneurysms may cause back or abdominal pain or a pulsatile abdominal mass. Rupture leads to life-threatening bleeding and shock.

Diagnosis relies on imaging, including CT angiography, MR angiography, abdominal ultrasound, or catheter angiography. Treatment depends on size, location, and rupture risk. Small unruptured aneurysms may be monitored with risk-factor management. Larger or enlarging aneurysms or intracranial aneurysms may be treated with endovascular approaches (stent grafts or coiling) or open surgical repair. Ruptured aneurysms require urgent resuscitation and definitive repair.

Prognosis and prevention: rupture carries high mortality; prognosis improves with timely treatment. Risk reduction includes blood pressure control, smoking cessation, and targeted screening in high-risk individuals.