In the wake of MP Madeline Joell's untimely death last month, many Bermudians were left with more questions than answers about brain aneurysms.

The young and energetic Paget East MP epitomised vitality and good health, and her passing left many wondering whether they, too, may be at risk.

The word "aneurysm'' is derived from the Latin "to widen''. An aneurysm is the widening of an arterial wall which causes a weak bulging spot that can sometimes bleed.

The cause of brain aneurysms is poorly understood, although a number of hereditary and environmental factors are thought to contribute. It's rare for an aneurysm to occur in either very young or very old people -- but aging is a factor in aneurysm formation.

Some studies suggest degenerative changes take place within the blood vessel wall causing it too weaken with age, increasing the likelihood of an aneurysm developing.

Unfortunately the vast majority of aneurysms are not diagnosed until after they've ruptured -- only ten to 15 percent are able to be diagnosed from their clinical symptoms.

Aneurysm rupture usually causes subarachnoid haemorrhage (SAH), where blood flows between the brain and the brain covering.

As an aneurysm ruptures, it often causes a severe, blinding headache which grows progressively worse. Symptoms include loss of consciousness, nausea, vision problems, sensitivity to sound, weak limbs, or an inability to understand words or speak.

In the US, a third of patients who suffer SAH will recover, one third will suffer disabilities and one third will die.

Director of Emergency Services at King Edward VII Memorial Hospital, Dr.

Edward Schultz, said the most common type of brain aneurysm is called the saccular, or "berry'', aneurysm which occurs in vessels at the bottom of the brain.

"Aortic aneurysms are completely different -- they're usually due to longstanding high blood pressure,'' he said.

"But saccular aneurysms are usually the result of a developmental defect in the wall of the artery which gets bigger and bigger over time until it ruptures.

"Although there is an increase in hypertension among people with saccular aneurysms, it's not the cause -- there are patients with saccular aneurysms who have normal blood pressure.'' Dr. Schultz said although strokes often occur when people are sleeping, the opposite is true of SAHs -- they most often occur during periods of activity such as while lifting something heavy, doing sports, even during sexual intercourse.

And he said there are a number of people in Bermuda with polycystic kidney disease, which is a risk factor for developing saccular aneurysms.

"People are overwhelmingly asymptomatic, with rare exceptions, until the aneurysm ruptures and a subarachnoid haemorrhage occurs,'' he said.

"When it does rupture, people describe it as the worst headache they've ever had.

"Some lose consciousness and lapse into a coma, some recover consciousness, and others have just a really bad headache... but if there's a massive bleed, there's a high mortality rate,'' he added.

Dr. Schultz said when a patient is admitted into KEMH emergency ward with symptoms of an aneurysm, the first step is to check their ABCs -- airway, breathing and circulation.

"It's crucial to maintain good oxygenation to the brain, and if their blood sugar is too high or too low it can contribute to brain injury,'' he noted.

"What we do next is conduct a thorough neurological examination and obtain a CAT Scan. 95 to 98 percent of subarachnoid haemorrhages from aneurysms can be detected with a helical scanner such as at KEMH.

"If we don't see any blood but have a high suspicion (that it is a SAH), we'll do a spinal tap to look for blood in the spinal fluid.

"But once we make the diagnosis, we'll need to transfer them to a neurosurgical centre by air ambulance for definitive care.'' Dr. Schultz said there are two major risks to contend with when a patient has suffered a SAH from a ruptured aneurysm.

Re-bleeding, which occurs within the first 24 hours of the first haemorrhage and is generally more severe than the first time.

The second risk is vasospasm, where the vessels contract, which tends to happen between two days and three weeks of the initial aneurysm.

"The patient is initially placed in the hospital's intensive care unit where their breathing, neurological status and blood pressure are monitored closely,'' said Dr. Schultz.

"But it's a very serious diagnosis and despite good care, a number of the patients will die.'' To learn more about aneurysms, check out the brain aneurysm webpage at www.neurosurgery.mgh.harvard.edu .

Serious diagnosis: Senior CT technician Maggie Sousa (above) points out the CAT Scan of a haemorrhage which occured as a result of a ruptured brain aneurysm. (Below) Emergency Services Director Dr. Edward Schultz said haemorrhages from ruptured brain aneurysms often result in a high mortality rate. Diagnosis of aneurysms are usually made with the aid of CAT scans, such as in the lower left panel. The white patch in the lower left panel on shows a large haemorrhage.

Photos by Ras Mykkal At a glance Subarachnoid haemorrhage (SAH) occurs when blood spills into the area that surrounds the brain. This type of haemorrhage is usually the result of a ruptured aneurysm.

Risk factors Middle Age: The incidence of aneurysm rupture increases through middle age, peaking in people between the ages of 40 and 60.

Gender: SAH affects women in 60 percent of all cases and men in 40 percent of all cases.

Family history: People with a family history of SAH caused by aneurysm may also be at higher risk, especially when two or more members of their immediate family have experienced this type of stroke. If there is a family history, consult a physician -- steps can be taken to prevent a rupture.

Cigarettes and alcohol: Cigarette smoking and excessive alcohol use have been shown to increase the risk of aneurysm rupture.