Craniotomy and Craniectomy
MEDICAL ANIMATION TRANSCRIPT: Your doctor may recommend a craniotomy or craniectomy procedure to treat a number of different brain diseases, injuries, or conditions. Your skull is made of bone, and serves as a hard, protective covering for your brain. Just inside your skull, three layers of tissue called meninges surround your brain. The thick, outermost layer is the dura mater. The middle tissue layer is the arachnoid mater, and the innermost layer is the pia mater. Between the arachnoid mater and the pia mater is the subarachnoid space, which contains blood vessels and a clear fluid called cerebrospinal fluid. Blood vessels, called bridging veins, connect the surface of your brain with the dura mater. Other blood vessels, called cerebral arteries, bring blood to your brain. Inside your skull, normal brain function requires a delicate balance of pressure between the blood in your blood vessels, the cerebrospinal fluid that surrounds your brain, and your brain tissue. This is called normal intracranial pressure. Increased intracranial pressure may result from brain tumors, head injuries, problems with your blood vessels, or infections in your brain or spinal cord. These conditions put pressure on your brain, and may cause it to swell or change shape inside your skull, which can lead to serious brain injury. Your doctor may recommend a craniotomy to remove abnormal brain tissue such as a brain tumor, a sample of tissue by biopsy, a blood clot called a hematoma, excess cerebrospinal fluid, or pus from an infection called an abscess. A craniotomy may also be done to relieve brain swelling; stop bleeding, called a hemorrhage; repair abnormal blood vessels; repair skull fractures; or repair damaged meninges. Finally, a craniotomy may also be done to treat brain conditions such as epilepsy, deliver medication to your brain, or implant a medical device such as a deep brain stimulator. The most common reason for a craniotomy is to remove a brain tumor. Before your procedure, you will be given general anesthesia to make you unconscious and pain-free. The skin on your scalp will be shaved over the location of the tumor. To begin, your surgeon will make an incision in your scalp. One or more small holes will be made in your skull. Then, your surgeon will connect the holes to create a circular piece of bone called a bone flap, and remove it. Your surgeon will make an incision in the dura mater to expose your brain. Then your tumor will be removed. The incision in the dura mater will be closed with sutures. Your surgeon will reattach the bone flap with metal plates and screws that will remain in your skull for life. You may have a variation on a craniotomy called a craniectomy, if your brain is very swollen or your skull is infected. Your surgeon may delay reattaching the bone flap until a later procedure, to allow time for the swelling to go down. At the end of either a craniotomy or a craniectomy, your scalp incision will be closed with staples, and your head will be wrapped in bandages. If you had a craniectomy, you will have another procedure called a cranioplasty at a later date, after the swelling goes down. At that time, your surgeon will reattach your bone flap with metal plates and screws, then close the skin incision with staples. After either procedure, you will stay in the hospital for several days. Your caregiver will check your brain function by asking you questions, and shining a light in your eyes. You may be given medication to prevent complications.