Aneurysm and Subarachnoid Hemorrhage
The neurosciences team at Scottsdale Healthcare Osborn Medical Center possesses the skills and the technology to treat patients with aneurysm and subarachnoid hemorrhage (SAH).
A brain (cerebral) aneurysm is a bulging, weak area in the wall of an artery that supplies blood to the brain. In most cases, a brain aneurysm causes no symptoms and goes unnoticed. In rare cases, the brain aneurysm ruptures, releasing blood into the skull and causing a stroke.
When a brain aneurysm ruptures, the result is called a subarachnoid hemorrhage. Depending on the severity of the hemorrhage, brain damage or death may result.
A person may inherit the tendency to form aneurysms, or aneurysms may develop because of hardening of the arteries (atherosclerosis) and aging. Some risk factors that can lead to brain aneurysms can be controlled, and others can't. The following risk factors may increase your risk of developing an aneurysm, or, if you’ve already had an aneurysm, may increase your risk of it rupturing:
- Family history. People who have a family history of brain aneurysms are twice as likely to have one as those who don't.
- Previous aneurysm. About 20 percent of patients with brain aneurysms have more than one.
- Gender. Women are twice as likely to develop a brain aneurysm or to suffer a subarachnoid hemorrhage as men.
- Race. African Americans have twice as many subarachnoid hemorrhages as whites.
- Hypertension. The risk of subarachnoid hemorrhage is greater in people with a history of high blood pressure (hypertension).
- Smoking. In addition to being a cause of hypertension, smoking may greatly increase the chances of a brain aneurysm rupturing.
Most brain aneurysms are discovered during tests for another, usually unrelated, condition. In other cases, an unruptured aneurysm will cause problems by pressing on areas within the brain. When this happens, a patient may suffer from severe headaches, blurred vision, changes in speech, and neck pain, depending on the areas of the brain that are affected and the severity of the aneurysm.
If you have any of the following symptoms or notice them in someone you know, please see a health professional immediately.
- Sudden, severe headache
- Neck pain
- Nausea and vomiting
- Sensitivity to light
- Fainting or loss of consciousness
An eye exam may show increased pressure within the brain, including swelling of the optic nerve or bleeding into the retina of the eye. The following tests may be used to diagnose cerebral aneurysm and determine the cause of bleeding within the brain:
- CT scan of the head
- CSF exam (spinal tap)
- MRI of the head
- Cerebral angiography or spiral CT scan angiography of the head to reveal the location and size of the aneurysm
- Electroencephalogram (EEG) if seizures occur
Subarachnoid hemorrhage (SAH)
SAH is bleeding in the area between the brain and the thin tissues that cover the brain. This area is called the subarachnoid space. SAH may be caused by:
- Bleeding from an arteriovenous malformation (AVM)
- Bleeding disorder
- Bleeding from a cerebral aneurysm
- Head injury
- Use of blood thinners
- Unknown cause
SAH, due to rupture of a cerebral aneurysm, occurs in approximately 10-15 out of 10,000 people. It is most common in patients age 20 to 60, and is slightly more common in women than men. Risks include:
- Aneurysms in other blood vessels
- Fibromuscular dysplasia
- High blood pressure
- History of polycystic kidney disease
The primary symptom is a severe headache that starts suddenly and often is worse near the back of the head. Patients often describe it as the "worst headache ever." The headache may start after a popping or snapping feeling in the head. Other symptoms include:
- Sudden or decreased consciousness and alertness
- Difficulty or loss of movement or feeling
- Mood and personality changes, including confusion and irritability
- Muscle aches (especially neck pain and shoulder pain)
- Nausea and vomiting
- Photophobia (light bothers or hurts the eyes)
- Stiff neck
- Vision problems, including double vision, blind spots, or temporary vision loss in one eye
A physical exam may show a stiff neck due to irritation by blood of the meninges, the tissues that cover the brain. Except those in a deep coma, persons with a subarachnoid hemorrhage may resist neck movement.
An eye exam may be performed. Decreased eye movements can be a sign of damage to the cranial nerves. In milder cases, no problems may be seen on an eye exam.
If your doctor thinks you may have a subarachnoid hemorrhage, a head CT scan may be immediately done. In some cases, the scan may be normal, especially if there has only been a small bleed. If the CT scan is normal, a lumbar puncture (spinal tap) should be performed. Patients with SAH will have blood in their spinal fluid.
CT scan angiography may be done to look for evidence of SAH and aneurism.
Cerebral angiography of blood vessels of the brain is better than CT angiography to show small aneurysms or other vascular problems. This test can pinpoint the exact location of the bleed and can tell if there are blood vessel spasms.
Transcranial Doppler ultrasound is used to look at blood flow in the arteries of the brain that run inside the skull. The ultrasound beam is directed through the skull. It can also detect blood vessel spasms and may be used to guide treatment.
Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) are occasionally used to diagnose a subarachnoid hemorrhage or find other associated conditions.