Brain Aneurysm

What is your disease?
A cerebral aneurysm (also known as an intracranial or intracerebral aneurysm) is a weak or thin spot on a blood vessel in the brain that balloons out and fills with blood causing out-pouching which has a potential for rupture or other related complications. Cerebral aneurysms can occur anywhere in the brain, but most are located along a loop of arteries that run between the underside of the brain and the base of the skull.

What are the symptoms of the disease?
Most cerebral aneurysms do not show symptoms until they either become very large or burst.  Small, unchanging aneurysms generally will not produce symptoms, whereas a larger aneurysm that is steadily growing may press on tissues and nerves.  Symptoms may include pain above and behind the eye; numbness, weakness, or paralysis on one side of the face; dilated pupils; and vision changes.  When an aneurysm hemorrhages, an individual may experience a sudden and extremely severe headache, double vision, nausea, vomiting, stiff neck, and/or loss of consciousness.  Patients usually describe the headache as “the worst headache of my life” and it is generally different in severity and intensity from other headaches patients may experience.  Warning headaches may result from an aneurysm that leaks for days to weeks prior to rupture.  Only a minority of patients have a sentinel headache prior to aneurysm rupture.

Other signs that a cerebral aneurysm has burst include nausea and vomiting associated with a severe headache, a drooping eyelid, sensitivity to light, and change in mental status or level of awareness.  Some individuals may have seizures.  Individuals may lose consciousness briefly or go into prolonged coma.  People experiencing this “worst headache,” especially when it is combined with any other symptoms, should seek immediate medical attention.

How is it diagnosed?
Most cerebral aneurysms go unnoticed until they rupture or are detected by brain imaging that may have been obtained for another condition.  Several diagnostic methods are available to provide information about the aneurysm and the best form of treatment.  The tests are usually obtained after a subarachnoid hemorrhage, to confirm the diagnosis of an aneurysm.

Plain CT head should be the first investigation to be performed particularly to look for presence for bleeding. Most of the cases CT will show evidence of blood in subarachnoid space although one should be aware that few patients might have normal scans within 24 hours of confirmed SAH Lumbar puncture is done to detect RBCs and xanthochromia as an evidence of SAH. LP is indicated in case where the clinical history is strongly suggestive of SAH with a negative CT or the patient presents many days after the episode with a negative CT scan.

Catheter Angiography or DSA is the most accurate investigations in diagnosis and evaluation of aneurysms causing the SAH. Cerebral angiography is performed once the diagnosis of SAH is made. This study assesses the ruptured aneurysm, vascular anatomy, presence of other aneurysms and secondary vasospasm. In particular, 3-D DSA is most accurate in evaluating assessment of intracranial aneurysms. Catheter angiography (DSA) findings can be negative in 10-20% of patients with SAH. If negative, it is advisable to repeat angiography a few weeks later. Magnetic resonance imaging (MRI) is also performed if no lesion is found on angiography to evaluate for unusual parenchymal pathologies causing SAH like cavernomas, tumors or vasculitis.

MR angiography can detect intracranial aneurysms, its sensitivity in detection of small intracranial aneurysm is poor. CT angiography is performed after intravenous injection of contrast and is a useful procedure for detection of aneurysm and for arterial blockage/stenosis. Although CT angiography has improved significantly in recent times, 3-D DSA remains the gold standard in detection and evaluation of intracranial aneurysms.

Why does it develop?
Most cerebral aneurysms are congenital, resulting from an inborn abnormality in an artery wall.  Cerebral aneurysms are also more common in people with certain genetic diseases, such as connective tissue disorders and polycystic kidney disease, and certain circulatory disorders, such as arteriovenous malformations. Other causes include trauma or injury to the head, high blood pressure, infection, tumors, atherosclerosis (a blood vessel disease in which fats build up on the inside of artery walls) and other diseases of the vascular system, cigarette smoking, and drug abuse.  Some investigators have speculated that oral contraceptives may increase the risk of developing aneurysms.

How is it treated?
Aneurysms can be treated by endovascular and surgical techniques. The primary goal of treatment is complete, permanent and safe aneurysm occlusion.

Microvascular clipping involves cutting off the flow of blood to the aneurysm.  Under anesthesia, a section of the skull is removed and the aneurysm is located.  The neurosurgeon uses a microscope to isolate the blood vessel that feeds the aneurysm and places a small, metal, clothespin-like clip on the aneurysm’s neck, halting its blood supply.  The clip remains in the patient and prevents the risk of future bleeding.  The piece of the skull is then replaced and the scalp is closed.  Clipping has been shown to be highly effective, depending on the location, shape, and size of the aneurysm.  In general, aneurysms that are completely clipped surgically do not return.

A related procedure is an occlusion, in which the surgeon clamps off (occludes) the entire artery that leads to the aneurysm.  This procedure is often performed when the aneurysm has damaged the artery.  An occlusion is sometimes accompanied by a bypass, in which a small blood vessel is surgically grafted to the brain artery, rerouting the flow of blood away from the section of the damaged artery.

Endovascular coiling is an alternative to surgery.  Once the patient has been anesthetized, the doctor inserts a hollow plastic tube (a catheter) into an artery (usually in the groin) and threads it, using angiography, through the body to the site of the aneurysm.  Using a guide wire, detachable coils (spirals of platinum wire) are passed through the catheter and released into the aneurysm.  The coils fill the aneurysm, block it from circulation, and cause the blood to clot, which effectively destroys the aneurysm.  A recent randomized, multicentre trial conducted in Europe and North America has shown that long-term clinical results were better with embolization than open surgery in certain subset of patients. Endovascular treatment and is usually the treatment of choice of patients with surgically poorly accessible aneurysms (posterior circulation, cavernous ICA aneurysms), in patients with medical risk factors and in patients with poor clinical status after the bleed.

Are there any alternatives?
No, only treatment options are surgical clipping or endovascular coiling. At present no alternative treatment other than mentioned is available .

What will happen if it is left untreated?
Aneurysms may burst and rebleed into the brain again with very high risk of causing serious complications including hemorrhagic stroke, permanent nerve damage, or death.  Once it has burst, the aneurysm has high chances to burst again and rebleed into the brain, and additional aneurysms may also occur.  A delayed but serious complication of subarachnoid hemorrhage is hydrocephalus, in which the excessive buildup of cerebrospinal fluid in the skull dilates fluid pathways called ventricles that can swell and press on the brain tissue.  Another delayed postrupture complication is vasospasm, in which other blood vessels in the brain contract and limit blood flow to vital areas of the brain.  This reduced blood flow can cause stroke or tissue damage. Once anurysm is treated than the treatment for all these complications can be started otherwise it would again be dangerous to start the treatment of vasospasm without treating aneurysm.

What am I supposed to do before surgery?
Preparation before surgery will vary,depending on whether the patient arrives at the emergency room with a ruptured aneurysm or whether the patient is considering coiling for an unrup­tured aneurysm.

A ruptured aneurysm is life threatening, and every patient is assessed for medical stability and treated as necessary. Once the patient has been stabilized, the medical team must find the source of the hemorrhage. This is typically accomplished with an angiogram or CT angiogram. The endovascular neurosurgeon then reviews the findings to determine whether the aneurysm should be treated with endovascular coiling or surgical clipping. The physician shares this recommendation with the patient and family. A patient with an unruptured aneurysm has time to prepare for a scheduled surgery and will typically undergo tests (e.g., blood test, electrocardiogram, chest X-ray) several days before surgery. In the doctor’s office, you will sign consent forms and complete paperwork regarding your medical history including allergies, medications, bleeding history, anesthesia reactions, and previous surgeries. Discuss all medications you are taking with your health care provider. Some medications need to be continued or stopped the day of surgery. Be sure to discuss all allergies. Also let your doctor know wheather you are pregnant or not.1. Stop taking all non-steroidal anti-inflammatory medicines 1 week before surgery. Stop taking coumadin 1 week before surgery. Some blood thinning medications are permitted or occasionally recommended prior to coiling. The doctor will give you specific instructions to either stop or start taking blood thinners. Additionally, stop smoking, chewing tobacco, and drinking alcohol 1 week before and 2 weeks after surgery as these activities can cause bleeding problems. No food or drink is permitted past midnight the night before surgery. 

Patients are admitted to the hospital the morning of the procedure. An intravenous (IV) line is placed in the arm. An anesthesiologist will explain the effects of anesthesia and its risks.

What surgery is being planned?

As a routine policy in Medanta Medicity and now the world over we offer endovascular coiling as first treatment option to the patient. Surgical clipping can be an option for the patients who are not fit for endovascular coiling either due to technical or medical reasons or for the one who will not be able to come for follow-ups.

What is the risk of surgery?
Rupture of the aneurysm is one of the most serious complications seen in either procedure. Reported rupture rates range from 2 percent to 3 percent for both coiling and clipping. Rupture can cause massive bleeding into the brain and subsequent coma or death.
Ischemic stroke (stroke secondary to decreased blood oxygen) is another serious complication frequently encountered in both clipping and coiling. The pattern and distribution of strokes varies according to the aneurysm location and procedure type.

The actual length of the procedure, the associated risks, the projected recovery time, and the expected prognosis (outcome) depend on both the location of the aneurysm, the presence and severity of hemorrhage, and the patient's underlying medical condition. Therefore, each individual case should be discussed with the treating endovascular neurosurgeon.

What should I watch out after discharge?
You may be advised not to participate in any strenuous activities. Your physician will instruct you about when you can return to work and resume normal activities.
Notify your physician to report any of the following:
fever and/or chills
increased pain, redness, swelling, or bleeding or other drainage from the insertion site
coolness, numbness and/or tingling, or other changes in the affected extremity
any changes in bodily functions or neurological changes, such as extreme headache, seizure, or loss of consciousness
Generally, a cerebral angiogram will be performed periodically after the procedure to assess the effectiveness of the coiling procedure. The first angiogram may be performed about 5-6 months after the procedure. Additional cerebral angiograms and/or other imaging procedures such as MRI/MRA may be performed at intervals to be determined by your physician based on your progress and previous imagings
After the surgery contact your Doctor if:
If your temperature exceeds 101° F or if the incision begins to separate or show signs of infection, such as redness, swelling, pain, or drainage.
Go to the nearest emergency room if you experience a large swelling or sudden pain at the puncture site, or loss of sensation, numbness or swelling of the leg.
Call if you experience a sudden severe headache, popping or snapping sensation in head, nausea and vomiting, or a stiff neck. These are signs of an aneurysm rupture.

D.RISKS OF THIS PROCEDURE
While majority of patients have an uneventful surgery and recovery, few cases may be associated with complications. These are seen infrequently and not all the ones listed below are applicable to one individual.  However it is important that you are aware of the complications/risks that may arise out of this procedure which are as below:
Infection
Bleeding which may warrant open procedure
CSF leak
Inadequate removal of the lesion
Worsening of the existing neurological deficit or development of fresh deficit

E.SIGNIFICANT RISKS AND RELEVANT TREATMENT OPTIONS
Vasospasm
Hydrocephalus
These are two risks associated with natural history of SAH.
The doctor has explained any significant risks and problems specific to me, and the likely outcomes if complications occur.