Think-A-Head Campaign Q&A
November 1, 2016
Q: What is “TBI”?
A: Traumatic Brain Injury is often just called “TBI”.
Q: What is a traumatic brain injury (TBI)?
A: A blow to the head can cause TBI, but not all blows to the head result in TBI. Whether or not there is damage to the brain after the blow depends on the circumstances and severity of the blow.
Q: What happens to the brain in TBI?
A: If the blow is severe enough, it can damage the brain in two ways. First, the blow can directly damage tissues. For example, the skull can fracture, blood vessels can rupture and leak blood in around the brain, and nerve fibers within the brain can be torn. After this first damage, the harmed brain may become swollen and blood supply to the brain may be reduced, causing further damage.
Q: What are some signs of traumatic brain injury (TBI)?
A: The signs of TBI can be very different depending on the severity of injury. A mild injury, also called a “concussion”, can cause confusion, disorientation, memory loss, and brief loss of consciousness, but the person stays awake after that with eyes open. A moderate injury causes a loss of consciousness for longer than 20 minutes; the person is lethargic but will open eyes when stimulated. A person with severe TBI is unconscious and the eyes do not open, even with stimulation.
Q: How is the diagnosis of TBI made?
A: It is very important to report exactly how the brain injury happened, if the patient lost consciousness and for how long, and any symptoms the patient had after the injury. In the emergency room, physicians and other healthcare providers will quickly assess the level of alertness, ability to open eyes and follow commands. If the injury is mild and there are no other concerns, imaging may not be necessary. If the injury is moderate or severe, patients will have imaging studies to assess any damage to the tissues of the brain and skull.
Q: Are there any other studies that can be done instead of a head CT?
MRI can also be used to look inside the head. This test uses magnetic fields instead of x-rays to image the brain. However, MRI is a much longer exam than CT and may take half an hour or more to complete. In order for young children to stay still for that long, they usually require sedation or full anesthesia to put them to sleep. This delays the production of images about your child’s condition in urgent cases. MRI is also not good at looking at imaging skull bones and may not show small fractures.
Q: Which imaging tests should be done?
A: The imaging test that is usually done first is called a Computed Tomography (CT or CAT) scan of the head (or sometimes called a brain CT scan). This test will have x-ray exposure, but is the quickest test to find fractures of the skull and bleeds in or around the brain. This test is also used to follow bleeds in and around the brain. When there is concern for torn nerve fibers, a Magnetic Resonance Imaging (MRI) of the brain is done. This imaging does not involve x-ray exposure, but it is not as fast as a CT scan and does not show skull fractures so well.
Q: What is a CT exam?
A: A CT exam uses x-rays to create higher quality of images of the soft tissues within the patient’s body as opposed to high quality images of the bones of the body created with standard x-rays exams. The images are presented as slices so we can see inside of the head. Analogy: A loaf of bread: It gathers the information of the entire loaf, inside and out. The information can be “sliced” like a loaf of bread so we can see the middle of the bread.
Q: I have heard radiation or CT scans may not be safe. Does my child have to have this test?
A: The information in the CT images is required for your child’s doctors to determine how to best care for your child’s injury. Some head injuries require specialized care on the same day. Others may not. Receiving the correct care at the right time is important and a benefit to your child. This benefit is far greater than any possible small risk of the x-rays—risks that we have no evidence clearly exist.
Q:Will the CT scan hurt?
A: No, a CT scan does not hurt. All your child will have to do is lay on the table on their back. We may have to use straps to hold your child’s head still, but this does not hurt.
CT scanner and table
Q: Should my child be shielded for the exam?
A: Since CT uses x-rays rotated around the head, shielding the head may obstruct important information about your child’s head. There is very little radiation to the body outside the head. Some hospitals may use body shields and this is not harmful, but the little radiation that does happen to the body comes from internal scatter of a very small number of x-rays and is likely not blocked by this shielding.
Q: Does my child need the injection of dye for a head CT?
A: Dye (contrast) is not generally needed for head CTs performed after head trauma.
Q: Does my child need to be sedated?
A: Since CT is a quick exam, you child only needs to be still for usually under a minute. This usually does not require sedation.
Q: How long will the CT take?
A: The CT itself will only take about 5 minutes as long as we do not have to repeat any images. The scan itself is only seconds long, once everything is set up.
Q: When will we get the CT results?
A: The results should be available within 30 minutes; this could take a little longer depending on many factors, though (such as the doctor is also taking care of another injured child at that moment).