Intracranial Hemorrhage

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1 BACKGROUND Intracranial hemorrhage, a type of stroke, is bleeding in the brain from a broken blood vessel. It represents 10-20% of all strokes, effects over 45,000 Americans per year and has a 2/3 mortality at one year. The short and long term costs are significant. Understanding and preventing this devastating problem is critically important and is the primary mission of several national organizations. The brain gets its nutrient supply from blood passing through blood vessels. However, when a blood vessel is damaged, bleeding can occur. The area of the brain near the bleeding may be damaged by direct pressure from the blood clot, and in other brain areas, the lack of oxygen and nutrients supply can result in even further injury. The severity of the injury is dependent upon the size of the clot, extent of direct brain injury and location of the bleed. Some brain areas are less tolerant to pressure and starvation, including the brain stem. Other areas can be disrupted without significant problems. Intracranial hemorrhage occurs for many reasons. The majority of sudden bleeds occurs in the setting of long-standing, poorly-controlled blood pressure (hypertension). Other causes include vessel abnormalities, like brain aneurysms or AVMs (arterio-venous malformations), tumors, use of blood thinners, and use of illegal drugs, like cocaine. There are several groups of people who are at increased risk. Hypertension, smoking, drug and alcohol abuse and poorly monitored blood thinner use are the most significant behavior risks that can be modified. RELEVANT ANATOMY The brain is divided into several parts. There are the right and left sides (hemispheres), the cerebellum and brainstem. Each part performs different functions. In most people, the left side is responsible for speech and movement in the right half of the body; while the right side is responsible for aspects of higher thought function and moves the left half of the body. The cerebellum is responsible for coordination and balance, and the brain stem contains many of the critical pathways for information to exit the brain. The blood vessels enter the skull at the base of the brain and wrap and penetrate deep into the tissue to provide oxygen and nutrients. SIGNS and SYMPTOMS of DISEASE The signs and symptoms are widely varied and are dependent upon the location and size of the hemorrhage. The type of neurologic sign and progression often can help localize the site of injury. Common symptoms include headache, nausea, vomiting, blurry or double vision, change in level of alertness, or loss of consciousness. These can be due to high generalized pressure in the head from the blood. Some symptoms help physicians identify which part of the brain is affected, and includes face, arm or leg weakness, paralysis, decreased sensation, numbness and tingling, difficulty speaking or understanding, loss of vision, difficulty with eye movements, imbalance and lack of coordination. A seizure may also be the first sign of problems. Many of these signs and symptoms are common to many brain injuries and may not reliably identify which person has had a hemorrhage or other type of stroke. Early evaluation in an emergency room is critical to identifying these people and starting medical care. Page 1 of 7

2 DIAGNOSTIC TESTS The usual tests performed include blood tests and imaging studies. Blood tests can be extensive, and can include blood counts (looking for certain abnormalities in the blood cells), bleeding studies (looking for delayed clotting), and drug and medication levels. The most commonly used imaging test is the CT scan. This is often done at the first suspicion of a hemorrhage, and repeated to follow the progress of the clot. Other imaging studies include an MRI, looking closely at the brain tissue and for other lesions potentially responsible for the bleeding. An angiogram may be used to study the anatomy of the blood vessels in the head, looking for potential blood vessel abnormalities. TREATMENT OPTIONS Intensive care observation, including; o Repeated imaging o Blood transfusion and medicines to reverse bleeding abnormalities o Anti-seizure medicine o Blood pressure control Invasive monitoring, including; o Placement of monitors into the brain to measure pressure o Placement of a ventriculostomy (catheter for spinal fluid drainage) to relieve backup of fluid in the brain, particularly if blood has spilled into the ventricles o Placement of catheters to measure blood pressure or heart function Surgery o For clot removal o For removal of the blood vessel abnormality o To release pressure on nearby normal tissue o To prevent herniation and death SURGICAL TECHNIQUE The goal of surgery is to reduce the pressure from the clot on nearby tissue that can be saved. The tissue directly disrupted by the hemorrhage is often significantly injured and not expected to recover immediately from surgery. The technique involves making a skin incision and removing a window of bone adequate to access the clot. When the goal is to release pressure alone, a large incision and window are made. The decision to attempt clot removal is individual and dependent upon its location and size. In some instances, the injured brain must be removed to remove the clot or relieve pressure. The bone is often returned, though may not be replaced if the swelling and pressure are extensive. The overlying skin is sewn closed. When the goal of surgery is clot evacuation alone, this can at times be performed through minimally invasive techniques, including endoscopic (camera assisted) or stereotactic (computer guided) needle removal of the clot. With these methods, no window is made and the clot removal is through a 1-inch hole in the skull. A hemorrhage in the cerebellum is often poorly tolerated and urgent surgery may be required to prevent pressure injury to the nearby brainstem. Surgery involves an incision in the back of the neck at the base of the skull. The overlying bone of the bottom of the skull is removed and the injured cerebellum and blood clot removed. A tube may be placed into the brain to measure pressure and drain cerebrospinal fluid (CSF). When the bleed is due to a blood vessel abnormality, surgery is directed at clot removal and resection of the abnormality. The surgical techniques to treat such problems are individual and are decided caseby-case. Page 2 of 7

3 SURGICAL RISKS When surgery is performed to remove brain clots, the brain must be exposed and manipulated. The manipulation may be minimized by careful technique, and may be improved with smaller less invasive surgeries. However, the largest risk to surgery is further brain injury, to the either the abnormal brain or nearby normal tissues, from manipulation during clot removal. This is more problematic when clots are deep in the brain, as more normal tissue has to be opened to find the clot. Less risk for neurological injury occurs when the bleed is at the brain surface, because less manipulation is needed. This original and additional injury can be either temporary or permanent, and depends upon age, extent and location of the bleed. Whether surgery is appropriate for any specific individual is a decision that must consider the potential for worsening any injury. All patients are not candidates for brain surgery. Another risk to surgery is the potential for repeated bleeding. The injured brain is fragile and surgery on this tissue may be followed by further bleeding. Other risks to surgery include a small risk of infection that may require oral or intravenous antibiotics or even more surgery. Seizures are a recognized problem following surgery for a brain bleed. Antiseizure medicines are commonly used to prevent and treat these problems. EXPECTED OUTCOME The hemispheres are large and can, at times, tolerate disruption and relearn certain functions at times. The brainstem is much smaller, and even a small bleed can be devastating. Outcomes are, therefore, highly variable. Overall, 1/3 to 2/3 of all people with a brain bleed do not survive more than six months. This may be due to the bleed itself or from some of the severe disability left, despite quick and aggressive care. (1.) Larger bleeds, (2.) poor function on arrival to the emergency room, (3.) older people, and (4.) blood inside the ventricles predict a worse outcome. The majority of survivors have some long term injury. However, ability to function well is not predictable and is a highly individual. Studies are still ongoing to help identify who will benefit from any surgery, and how to achieve the best outcomes. AUTHOR Shaye Moskowitz, M.D. Ph.D. Page 3 of 7

4 RELEVANT TERMS 1. National Stroke Association ( the organization founded to promote education, prevention and research about strokes. 2. American Stroke Association ( a component of the American Heart Association focused on stroke prevention, education, treatment and research. 3. hypertension: high blood pressure 4. hemorrhage: bleed 5. CT (computerized tomography) scan: an imaging test of the brain using x-rays to look for blood in the inside of the brain 6. MRI (magnetic resonance imaging): another imaging test using strong magnets to look at brain tissue 7. angiogram: an invasive test where a catheter is inserted into an artery in the groin and threaded up to the arteries of the brain. A dye is injected and x-ray pictures are taken of the blood vessels. 8. herniation; when the brain tissue is forced into unusual places within the skull, often causing pressure on nearby normal tissue 9. endoscopic: surgery done with a small incision and assisted with a small camera 10. CSF (cerebrospinal fluid): the normal fluid in and around the brain and spinal cord that cushions and irrigates the delicate nerve tissue 11. ventricles: the normal spaces within the brain that contain pockets of CSF 12. ventriculostomy: a tube placed into the ventricle to drain fluid outside the head and monitor pressure in the brain Page 4 of 7

5 FIGURES Figure 1 shows a surface view of the brain with some basic anatomy: right and left hemisphere, cerebellum, and brainstem Page 5 of 7

6 Figure 2 shows a slice image of the brain where on the left side, the berry like area represents a deep bleed. Page 6 of 7

7 Figure 3 shows a slice from a CT Scan. The outer white ring is the skull. However, the large inner white region represents the area of the bleeding. This patient is not expected to move his leg or arm on the left side. Page 7 of 7