Aneurysms can occur anywhere in the body but are particularly dangerous when it arises in areas like the brain. It can even lead to death in these instances. Since aneurysms that are unruptured usually do not cause any signs or symptoms, a person could have a brain aneurysm for long periods of time without knowing it. However, once the aneurysm bursts the symptoms arise suddenly, are severe and can even lead to death in a short period of time.
An aneurysm is a bulging in the wall of an artery. It occurs due to weakening of the tissue in the artey wall. This can be inherited and form during prior to birth, occur with head trauma or infections, hypertension (high blood pressure) and with diseases like systemic lupus erythematosus (SLE). Cigarette smoking, alcohol abuse and illicit drug use are some of the risk factors that may increase the likelihood of a brain aneurysm arising.
With the artery wall being weakened in one area, it balloons due to the pressure of the blood within it. There is usually no problem as long as the wall remains intact and the ballooning is not large enough to press on brain tissue. However, any leak or rupture compromises blood flow to certain parts of the brain. Since the brain is a very oxygen-sensitive organ, symptoms will arise almost instantly when this ballooning bursts.
It is difficult to estimate the prevalence of brain aneurysms largely due to the lack of symptoms in an unruptured aneurysm. Therefore many people never discover the presence of these aneurysms during the course of life. Brain aneurysms are found in as many as 8% of autopsies. It occurs in both men and women equally before the age of 40 years but becomes more common in women with advancing age.
How deadly are brain aneurysms?
Although large unruptured brain aneurysms can press on the brain and cause symptoms, these are not usually serious of life threatening. Rupture of a brain aneurysm can lead to a stroke. This is known as a hemorrhagic stroke where blood pouring out of the ruptured aneurysm affects the oxygen supply to part of the brain. Hemorrhagic strokes are the less common type of stroke but are still potentially fatal.
Read more on hemorrhagic stroke.
A ruptured brain aneurysm causes bleeding within the cranial cavity. Most of the time this occurs between the brain and the meninges (lining around the brain). This is known as a subarachnoid hemorrhage and when it occurs due to a ruptured aneurysm, it results in death in about 65% of cases. According to studies, a ruptured aneurysm that results in a subarachnoid hemorrhage leads to death in:
- 10% of cases even before receiving medical attention.
- 25% of cases within 24 hours.
- 40% of cases within 3 months.
It is important to note that hemorrhagic stroke accounts for less than 20% of all strokes. The majority of strokes are ischemic in nature where a blood clot (thrombus or embolism) obstructs a narrowed artery thereby interrupting blood supply to certain areas of the brain. A stroke is a result of death of a portion of this brain tissue.
What are brain aneurysm symptoms?
Most of the time there are no signs and symptom of unruptured brain aneurysms. This means that the aneurysm has not burst and is not leaking. Most people will never know that these aneurysms exist. However, a large unruptured aneurysm can press on the brain and cause symptoms. The greater concern is a ruptured (burst) brain aneurysm. It presents with severe symptoms and can lead to death within minutes, hours or days.
Symptoms of these large unruptured aneurysms in the brain depend on the location of the aneurysms and its size. For example if the aneurysm presses on certain cranial nerves or brain centers it can cause symptoms like blurred vision or alterations in speech. Headaches or neck pain are some of the other possible symptoms that may occur. When a brain aneurysm bursts then the symptoms arise suddenly and are usually severe.
Read more on signs of a stroke.
Head and Face Pain
A headache is often cited as a characteristic symptom but is not always present in every instance of a rupture brain aneurysm. The headache when it does occur is of a sudden onset and very severe. A person will report an uncharacteristically severe headache even if there was a history of severe headaches. It may also be accompanied by face pain particularly when the aneurysm occurs in the internal carotid artery.
Neck Pain and Stiffness
Symptoms similar to meningitis occurs when the blood irritates the meninges. Characteristic meningitis symptoms like neck pain, neck stiffness and light sensitivity (photophobia) may arise. In addition there may also be increased sensitivity of the skin and even to sound (sonophobia). Sometimes fever, nausea and vomiting may also arise as a result of autonomic disturbances. In these cases meningitis may be incorrectly suspected.
As with an ischemic stroke, visual symptoms often arise beyond the sensitivity to light. These visual disturbances include blurred vision and/or double vision. Defects in the field of vision may also occur. These visual symptoms are typically one-sided and may also be accompanied by a drooping eyelid and/or dilated pupil. There may be accompany pain and behind the affected eye.
Seizures (‘fits’) can also occur when a brain aneurysm ruptures. In fact it may occur in as many as 1 in 4 cases of a subarachnoid hemorrhage. Seizures arise due to a disturbance in brain activity which may isolated to one part of the brain and specifically in one hemisphere of the brain (focal) or may involve both hemispheres (generalized). These seizures may not always arise immediately once a rupture occurs but can be delayed by up to 24 hours.
- Speech difficulty.
- One-sided numbness, weakness or paralysis.
- Confusion, reduced alertness and memory loss.
- Loss of consciousness (in about 50% of cases).
- Disturbances in breathing, heart rate and blood pressure.
NOTE: A brain aneurysm is a very serious condition and needs regular monitoring if surgery is not deemed immediately necessay. In addition medication may be prescribed to reduce the risk of a rupture. Always consult with a medical doctor about the risks of a brain aneurysm and the treatment that is necessary.