Chest CT (Computed Tomography) and brain CT are two different tests that use different scanning ranges and equipment locations. Often, medical facilities will have different CT machines for different parts of the body, so it is possible to have both a chest CT and a brain CT taken at the same time. This allows the imaging information of both the chest and the brain to be obtained in the same exam so that the doctor can make a thorough evaluation and diagnosis. The exact procedure and order of the scans will vary depending on the medical facility, and it is best to consult with your doctor or medical technician prior to performing the exam to ensure that you receive accurate instructions and arrangements.