The brain bulge

A brain aneurysm is the commonest reason for subarachnoid haemorrhage occurring in the absence of any head injury, writes Dr Vikram Huded

A brain aneurysm is a fatal brain condition that can affect anyone at any age, but it’s treatable! Stroke is predominantly of three types — Ischemic stroke (blockage of blood vessels causing brain damage due to lack of blood flow); Intracerebral haemorrhage (bleeding inside the brain usually resulting from rupture of very small blood vessels due to high blood pressure); Subarachnoid haemorrhage (SAH) (bleeding over the surface of the brain). Subarachnoid haemorrhage is maybe the least known stroke type because of its lower incidence compared to the other two, but it is possibly the most devastating type of stroke.

Brain aneurysm is the commonest reason for subarachnoid haemorrhage occurring in the absence of any head injury. Subarachnoid haemorrhage was in focus early this year when the Game of Thrones star Emilia Clarke revealed that she suffered subarachnoid haemorrhage two times in between the initial seasons of the popular series. She made a remarkable recovery both times and successfully completed the eight seasons of the series.

Basic Instinct star Sharon Stone wrote in her memoir The beauty of living twice about the near-death experience when she was struck by subarachnoid haemorrhage in 2001. She recovered fully but it took seven years, she revealed. Mortality before modern medical management used to remain as high as 45% and many of the patients used to remain disabled for life after subarachnoid haemorrhage.

What is a brain aneurysm?

A brain aneurysm is a balloon-like outpouching affecting the blood vessels of the brain. Haemorrhage happens when the wall of the balloon becomes weak enough and ruptures.

Watch out for these symptoms

Brain aneurysms usually go undetected until the time they rupture and cause subarachnoid haemorrhage. When subarachnoid haemorrhage occurs, patients develop sudden severe headaches often termed as a “thunderclap headache” or “the worst headache of life”. This is usually accompanied by nausea or vomiting.

After some leakage, the rupture point gets sealed temporarily in most cases but it can rupture again at any time. When the amount of blood leakage is more, patients become unconscious and many unfortunate patients succumb even before reaching the hospital. Less commonly, aneurysms can produce less intense symptoms like vision problems, drooping of eyelids, mild headaches etc. In the United States of America, the prevalence of unruptured aneurysms is estimated to be one in 50 persons.

According to one large study published in Lancet involving patients from many countries, the prevalence of unruptured aneurysms is 3.2% in the population without any other known diseases. The average age for aneurysm diagnosis is 50 years and overall it is more common in females.

Why does an aneurysm develop?

The precise reason for aneurysm formation is yet to be known. However, uncontrolled high blood pressure and smoking are known to be prominent risk factors for aneurysm development and rupture.

In some cases, the family history of brain aneurysm also plays a significant role. Patients with polycystic kidneys or connective tissue disorders are prone to aneurysm development.

The diagnosis

The diagnosis is usually confirmed by a CT or MRI scan with angiography. It is recommended to perform a periodic brain scan even in the absence of symptoms in high-risk patients, such as one with positive family history.

The treatment

It depends on whether an aneurysm has ruptured and a subarachnoid haemorrhage has happened or if it is detected after the minor symptoms. In the case of subarachnoid haemorrhage, treatment has to be done on an emergency basis. While in other cases it will be elective or planned treatment. Unfortunately, there is no medicine which can dissolve the aneurysm and heal the abnormal blood vessels. With science advancing by leaps and bounds, there are minimally invasive procedures and the finest devices available which can tackle these challenging conditions very well.

(The author is an interventional neurologist.)