Cerebral Aneurysm. Multimedia Health Education. Disclaimer

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1 Disclaimer This movie is an educational resource only and should not be used to manage neurological health. All decisions about the management of must be made in conjunction with your Physician or a licensed healthcare provider.

2 MULTIMEDIA HEALTH EDUCATION MANUAL TABLE OF CONTENTS SECTION CONTENT 1. Normal Brain Anatomy a. Introduction b. Sections of the Brain c. Lobes of the Brain d. Cerebrum e. Cerebral Cortex f. Inner Brain Structures 2. a. What is a? b. Symptoms c. Causes and Risk Factors 3. Treatment Options a. Diagnosis b. Conservative Treatment c. Surgical Treatment d. Post Operative Guidelines e. Surgical Treatment f. Post Operative Guidelines g. Risks and Complications

3 INTRODUCTION 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. The bulging aneurysm can put pressure on a nerve or surrounding brain tissue. It may also leak or rupture, spilling blood into the surrounding tissue. This is referred to as a cerebral hemorrhage and is a medical emergency. In order to learn more about cerebral aneurysm, it is important to understand the normal anatomy of the brain.

4 Unit 1: Normal Brain Anatomy Sections of the Brain The brain is the most complex part of the human body. This three-pound organ is the seat of intelligence, interpreter of the senses, initiator of body movement, and controller of behavior. Lying in its bony shell and washed by protective fluid, the brain is the source of all the qualities that define our humanity. Sections of the Brain All the parts of the brain work together, but each part has its own special properties. The brain can be divided into three basic units: the forebrain, the midbrain, and the hindbrain. (Refer fig. 1 to 5) Forebrain The forebrain is the largest and most highly developed part of the human brain. It consists primarily of the cerebrum and structures of the inner brain. (Fig. 1) Midbrain The uppermost part of the brainstem is the midbrain, which controls some reflex actions and is part of the circuit involved in the control of eye movements and other voluntary movements. Hindbrain The hindbrain includes the upper portion of the spinal cord, the brain stem and the cerebellum. The hindbrain controls the body s vital functions such as respiration and heart rate. Cerebrum (Fig. 2) Brainstem (Fig. 3) The cerebellum coordinates movement and is involved in learned rote movements. When you play the piano or hit a tennis ball you are activating the cerebellum. (Refer fig. 1 to 5)

5 Unit 1: Normal Brain Anatomy (Refer fig. 1 to 5) Spinal Cord (Fig. 4) Cerebellum (Fig. 5) Lobes of the Brain Each cerebral hemisphere can be divided into sections, or lobes, each of which specializes in different functions. To understand each lobe and its specialty we will take a tour of the cerebral hemispheres, starting with the two frontal lobes, which lie directly behind the forehead. Frontal Lobe When you plan a schedule, imagine the future, or use reasoned arguments, these two lobes do much of the work. One of the ways the frontal lobes seem to do these things is by acting as short-term storage sites, allowing one idea to be kept in mind while other ideas are considered. Front Lobe (Fig. 6) In the rearmost portion of each frontal lobe is a motor area, which helps control voluntary movement. A nearby place on the left frontal lobe called Broca s area allows thoughts to be transformed into words. (Refer fig. 6)

6 Unit 1: Normal Brain Anatomy Parietal Lobe When you enjoy a good meal the taste, aroma, and texture of the food two sections behind the frontal lobes called the parietal lobes are at work. The forward parts of these lobes, just behind the motor areas, are the primary sensory areas. Parietal Lobe (Fig. 7) These areas receive information about temperature, taste, touch, and movement from the rest of the body. Reading and arithmetic are also functions in the repertoire of each parietal lobe. (Refer fig. 7) Occipital Lobe As you look at the words and pictures on this page, two areas at the back of the brain are at work. These lobes are called the occipital lobes. They function to process images from the eyes and link that information with images stored in memory. Damage to the occipital lobes can cause blindness. (Refer fig. 8) Temporal Lobe These lobes lie in front of the visual areas and nest under the parietal and frontal lobes. Whether you appreciate symphonies or rock music, your brain responds through the activity of these lobes. At the top of each temporal lobe is an area responsible for receiving information from the ears. Occipital Lobe (Fig. 8) Temporal Lobe (Fig. 9) The underside of each temporal lobe plays a crucial role in forming and retrieving memories, including those associated with music. Other parts of this lobe seem to integrate memories and sensations of taste, sound, sight, and touch. (Refer fig. 9)

7 Unit 1: Normal Brain Anatomy Cerebrum When people see pictures of the brain it is usually the cerebrum that they notice. The cerebrum sits at the topmost part of the brain and is the source of intellectual activities. It holds your memories, allows you to plan, enables you to imagine and think. It allows you to recognize friends, read books, and play games. Cerebrum (Fig. 10) The cerebrum is split into two halves (hemispheres) by a deep fissure. Despite the split, the two cerebral hemispheres communicate with each other through a thick tract of nerve fibers that lies at the base of this fissure. Although the two hemispheres seem to be mirror images of each other, they are different. For instance, the ability to form words seems to lie primarily in the left hemisphere, while the right hemisphere seems to control many abstract reasoning skills. For some as-yet-unknown reason, nearly all of the signals from the brain to the body and vice-versa cross over on their way to and from the brain. This means that the right cerebral hemisphere primarily controls the left side of the body and the left hemisphere primarily controls the right side. When one side of the brain is damaged, the opposite side of the body is affected. For example, a stroke in the right hemisphere of the brain can leave the left arm and leg paralyzed. (Refer fig. 10) The Cerebral Cortex Coating the surface of the cerebrum and the cerebellum is a vital layer of tissue the thickness of a stack of two or three dimes. It is called the cortex, from the Latin word for bark. Most of the actual information processing in the brain takes place in the cerebral cortex. When people talk about "gray matter" in the brain they are talking about this thin rind. The Cerebral Cortex (Fig. 11) The cortex is gray because nerves in this area lack the insulation that makes most other parts of the brain appear to be white. The folds in the brain add to its surface area and therefore increase the amount of gray matter and the quantity of information that can be processed. (Refer fig. 11)

8 Unit 1: Normal Brain Anatomy Inner Brain Structures Deep within the brain lie structures that are the gatekeepers between the spinal cord and the cerebral hemispheres. These structures not only determine our emotional state, they also modify our perceptions and responses depending on that state, and allow us to initiate movements that you make without thinking about them. (Fig. 12) Like the lobes in the cerebral hemispheres, the structures described below come in pairs: each is duplicated in the opposite half of the brain. (Refer fig. 12) Hypothalamus The hypothalamus is about the size of a pearl and directs a multitude of important functions. It wakes you up in the morning, and gets the adrenaline flowing during a test or job interview. The hypothalamus is also an important emotional center, controlling the molecules that make you feel exhilarated, angry, or unhappy. (Refer fig. 13) Hypothalamus (Fig. 13) Thalamus Near the hypothalamus lies the thalamus, a major clearinghouse for information going to and from the spinal cord and the Cerebrum. (Refer fig. 14) Thalamus (Fig. 14) Hippocampus An arching tract of nerve cells leads from the hypothalamus and the thalamus to the hippocampus. (Refer fig. 15)

9 Hippocampus This tiny nub acts as a memory indexer sending memories out to the appropriate part of the cerebral hemisphere for long-term storage and retrieving them when necessary. (Refer fig. 15) Unit 1: Normal Brain Anatomy (Fig. 15) Basal Ganglia The basal ganglia are clusters of nerve cells surrounding the thalamus. They are responsible for initiating and integrating movements. Parkinson s disease, which results in tremors, rigidity, and a stiff, shuffling walk, is a disease of nerve cells that lead into the basal ganglia. (Refer fig. 16) (Fig. 16)

10 What is a? Unit 2: 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. The bulging aneurysm can put pressure on a nerve or surrounding brain tissue causing symptoms. It may also leak or rupture, spilling blood into the surrounding brain tissue. This is referred to as a hemorrhagic stroke. The most common type of hemorrhagic stroke is called a subarachnoid hemorrhage and causes bleeding between the brain and the tissues that cover the brain. A ruptured cerebral aneurysm is a medical emergency that results in death in approximately 50% of cases. 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. Most cerebral aneurysms, particularly those that are very small, do not bleed or cause other problems. What are the Symptoms? 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 of a growing aneurysm may include: Pain above and behind the eye Numbness, weakness, or paralysis on one side of the Dilated pupils Vision changes When an aneurysm hemorrhages (ruptures), an individual may experience: A sudden and extremely severe headache Double vision Nausea and vomiting Stiff neck Loss of consciousness Drooping eyelid Light sensitivity Change in mental status Seizures Coma Sentinel or warning headaches may result from an aneurysm that leaks small amounts of blood for days to weeks prior to rupture. The headache is severe but occurs without other symptoms. Only a minority of patients have a sentinel headache prior to aneurysm rupture. Patients usually describe the headache associated with a ruptured aneurysm as the worst headache of my life and it is generally different in severity and intensity from other headaches patients may experience. People experiencing this worst headache, especially when it is combined with any other symptoms, should seek immediate medical attention as this is a medical emergency.

11 What causes a? Unit 2: 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 of cerebral aneurysm include: Trauma or injury to the head High blood pressure Infection (Aneurysms that result from an infection in the arterial wall are called mycotic aneurysms.) Tumors (Cancer-related aneurysms are often associated with primary or metastatic tumors of the head and neck.) 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 Drug abuse, particularly the habitual use of cocaine Some investigators have speculated that oral contraceptives may increase the risk of developing aneurysms. Brain aneurysms can occur in anyone, at any age. They are more common in adults than in children and slightly more common in women than in men. People with certain inherited disorders are also at higher risk. All cerebral aneurysms have the potential to rupture and cause bleeding within the brain. The incidence of reported ruptured aneurysm is about 10 in every 100,000 persons per year, most commonly in people between ages 30 and 60 years. Possible risk factors for cerebral aneurysm rupture include: Hypertension Alcohol abuse Drug abuse (particularly cocaine) Smoking In addition, the condition and size of the aneurysm affects the risk of rupture.

12 Diagnosis Unit 3: Treatment Options 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 to your doctor about the aneurysm and the best form of treatment. Angiography This is a dye test used to analyze the arteries or veins. An intracerebral angiogram can detect the degree of narrowing or obstruction of an artery or blood vessel in the brain, head, or neck, and can identify changes in an artery or vein such as a weak spot like an aneurysm. It is used to diagnose stroke and to precisely determine the location, size, and shape of a brain tumor, aneurysm, or blood vessel that has bled. This test is usually performed in a hospital angiography suite. Magnetic resonance imaging (MRI) The tests are usually obtained after a subarachnoid hemorrhage, to confirm the diagnosis of an aneurysm. These tests may include: Computed tomography (CT) Angiography Magnetic resonance imaging (MRI) Cerebrospinal Fluid analysis Computed tomography (CT) CT of the head is a fast, painless, noninvasive diagnostic tool that can reveal the presence of a cerebral aneurysm and determine, for those aneurysms that have burst, if blood has leaked into the brain. This is often the first diagnostic procedure ordered by a physician following suspected rupture. X-rays of the head are processed by a computer as two-dimensional cross-sectional images, or slices, of the brain and skull. Occasionally a contrast dye is injected into the bloodstream prior to scanning. This process, called CT angiography, produces sharper, more detailed images of blood flow in the brain arteries. CT is usually conducted at a testing facility or hospital outpatient setting. Following the injection of a local anesthetic, a flexible catheter is inserted into an artery and threaded through the body to the affected artery. A small amount of contrast dye (one that is highlighted on x-rays) is released into the bloodstream and allowed to travel into the head and neck. A series of x-rays is taken and changes, if present, are noted. MRI uses computer-generated radio waves and a powerful magnetic field to produce detailed images of the brain and other body structures. Magnetic resonance angiography (MRA) produces more detailed images of blood vessels.

13 Unit 3: Treatment Options Diagnosis Magnetic resonance imaging (MRI) The images may be seen as either three-dimensional pictures or two-dimensional crossslices of the brain and vessels. These painless, noninvasive procedures can show the size and shape of an unruptured aneurysm and can detect bleeding in the brain. Cerebrospinal Fluid analysis This test may be ordered if a ruptured aneurysm is suspected. Following application of a local anesthetic, a small amount of this fluid (which protects the brain and spinal cord) is removed from the subarachnoid space located between the spinal cord and the membranes that surround it by surgical needle and tested to detect any bleeding or brain hemorrhage. In patients with suspected subarachnoid hemorrhage, this procedure is usually done in a hospital. Conservative Treatment Measures Not all cerebral aneurysms burst. Some patients with very small aneurysms may be monitored to detect any growth or onset of symptoms and to ensure aggressive treatment of coexisting medical problems and risk factors. Each case is unique, and considerations for treating an unruptured aneurysm include: Type, size, and location of the aneurysm Risk of rupture Patient s age, health, and personal and family medical history Risk of treatment Patients should ideally consult with at least two specialists to determine the best course of treatment for an unruptured cerebral aneurysm. One such specialist is a cerebrovascular neurosurgeon who specializes in open brain surgery and the other is an interventional neuroradiologist or endovascular surgeon who is specialized in minimally invasive treatment options. A neurologist, a brain specialist who does not perform surgery, may also be part of the treatment team. If your treatment team of specialists decides a minimally invasive approach is indicated you will undergo a procedure called Endovascular embolization. Endovascular embolization is a minimally invasive procedure that is an alternative to surgery. It is performed by a neuroradiologist or endovascular surgeon.

14 Conservative Treatment Measures 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) or small latex balloons are passed through the catheter and released into the aneurysm. The coils or balloons fill the aneurysm, block it from circulation, and cause the blood to clot, which effectively destroys the aneurysm. A similar option includes placing a stent at the neck of the aneurysm after placing the coils to keep the coils from protruding into the artery. Endovascular Embolization may need to be performed more than once during the patient s lifetime due to the risk of rebleeding. The main risks of this procedure include rupture of the aneurysm during the procedure, damage to the artery, and bleeding causing brain damage. Unit 3: Treatment Options (Fig. 17) (Fig. 18) (Refer fig. 17 to 20) (Fig. 19) (Fig. 20)

15 Conservative Treatment Measures Unit 3: Treatment Options Other conservative treatment options your doctors may recommend depending on your particular circumstances may include: Anticonvulsants to prevent seizures Analgesics to treat headache Calcium channel-blocking drugs to treat vasospasm Sedatives may be ordered if the patient is restless Blood pressure medications to control high blood pressure Smoking cessation Avoiding cocaine use or other stimulant drugs Patients who have suffered a subarachnoid hemorrhage often need rehabilitative, speech, and occupational therapy to regain lost function and learn to cope with any permanent disability. Consult with a doctor about the benefits and risks of taking aspirin or other drugs that thin the blood. Women should check with their doctors about the use of oral contraceptives. Surgical Treatment If conservative treatment measures fail or are not an option in your particular situation, your treatment team may recommend open brain surgery. Surgery to treat cerebral aneurysm is performed by a cerebrovascular neurosurgeon in the hospital operating room with the patient under general anesthesia. There are two surgical options available for treating cerebral aneurysms: Microvascular clipping and Arterial Occlusion with or without bypass. Microvascular clipping involves cutting off the flow of blood to the aneurysm by applying a clip to the neck or base of 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. (Fig. 21) (Refer fig. 21 to 26)

16 Unit 3: Treatment Options Surgical Treatment 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. Microvascular 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. (Fig. 22) Arterial Occlusion involves the surgeon clamping off (occluding) the entire artery that leads to the aneurysm. This procedure is often performed when the aneurysm has severely damaged the artery and clipping is not an option. It may be accompanied with bypass to reroute the blood around the occluded artery. Under anesthesia, a section of the skull is removed and the aneurysm is located. (Fig. 23) If bypass is to be performed, a vein, usually from the leg, will be harvested. (Refer fig. 21 to 26) (Fig. 24) (Fig. 25)

17 Unit 3: Treatment Options Surgical Treatment The neurosurgeon uses a microscope to isolate the artery that feeds the aneurysm. The surgeon then occludes the artery with special surgical instruments. The harvested vein is then attached above and below the occlusion with sutures to reroute the blood flow around the occluded artery. The piece of the skull is then replaced and the scalp is closed. (Fig. 26) (Refer fig. 21 to 26) Post Operative Guidelines After surgery your surgeon will give you guidelines to follow depending on the type of repair performed and the surgeon s preference. Common Post-operative guidelines following cerebral aneurysm surgery include: You will be transferred to ICU after surgery for close monitoring. You will probably stay in the hospital 4-6 days if the aneurysm has not ruptured prior to surgery and no complications occur. The hospital stay can be much longer for ruptured aneurysms or if complications occur. You may hear a clicking noise at the incision site on the skull. This is a normal part of the bone healing and may take 6-12 months to fully heal. Headaches are common after brain surgery and can continue for a long time. Your doctor can prescribe medications for pain relief. Keep the incisions clean and dry. You may shower once the dressings are removed unless otherwise directed by your surgeon. You will be given specific instructions regarding activity and rehabilitation. It is important to keep all your post operative appointments with your surgeon to ensure a good outcome. Eating a healthy diet and not smoking will promote healing. Risks and Complications As with any major surgery there are potential risks involved. The decision to proceed with the surgery is made because the advantages of surgery outweigh the potential disadvantages. It is important that you are informed of these risks before the surgery takes place.

18 Risks and Complications Unit 3: Treatment Options Complications can be medical (general) or specific to brain surgery. Medical complications include those of the anesthetic and your general well being. Almost any medical condition can occur so this list is not complete. Complications include: Allergic reactions to medications Blood loss requiring transfusion with its low risk of disease transmission Heart attacks, strokes, kidney failure, pneumonia, bladder infections Complications from nerve blocks such as infection or nerve damage Serious medical problems can lead to ongoing health concerns, prolonged hospitalization, or rarely death. Complications are rare after cerebral aneurysm surgery, but unexpected events can follow any operation. Factors influencing the development of complications include the location, type and size of the aneurysm, as well as whether the aneurysm has ruptured prior to surgery. Aneurysms that have not ruptured prior to surgery have less associated risk and complications than do ruptured aneurysms. Your surgeon feels that you should be aware of complications that may take place so that your decision to proceed with this operation is taken with all relevant information available to you. Specific complications of surgery can include: Damage to other blood vessels Bleeding Stroke Infection Seizures Death Brain swelling

19 Unit 3: Treatment Options Risk factors that can negatively affect adequate healing after surgery include: (Fig. 27)

20 Unit 3: Disclaimer Summary A good knowledge of this procedure will make the stress of undertaking the procedure easier for you to bear. The decision to proceed with the procedure is made because the advantages of the procedure outweigh the potential disadvantages. It is important that you are informed of these risks before the procedure. Disclaimer Although every effort is made to educate you on and take control, there will be specific information that will not be discussed. Talk to your doctor or health care provider about any concerns you have. You must not proceed until you are confident that you understand this procedure, particularly, the complications.

21 YOUR SURGERY DATE READ YOUR BOOK AND MATERIAL VIEW YOUR VIDEO /CD / DVD / WEBSITE PRE - HABILITATION ARRANGE FOR BLOOD MEDICAL CHECK UP ADVANCE MEDICAL DIRECTIVE PRE - ADMISSION TESTING FAMILY SUPPORT REVIEW Physician's Name : Physician's Signature: Date : Patient s Name : Patient s Signature: Date :