Answer: A computed axial tomography scan is good for observing anatomical brain changes, such as bone damage, tumors, or intracranial bleeding.
A computed axial tomography scan (also called a CAT or CT scan) is a frequently tly used technique in brain imaging. It is essentially an X-ray that uses computer technology to create a three-dimensional image of the brain. To collect a CT scan, the patient lies down and enters into the machine, which consists of a spinning X-ray emitting device that begins collecting data starting at the top of the head to the bottom of the head as the person moves through the opening of the machine.
Because the CAT scan is using X-rays, it is useful for imaging the anatomy of the brain. With x-rays, the tissue that is more dense comes up as white. For example, the bones of the cranium will come up as white. If there are major discontinuities in the structure, or breaks in the surface of the cranium or the softer bones in the sinus, these will appear in a CAT scan image. Brain tumors have an increased density compared to soft brain tissue. Tumors tend to appear in CT scans as well.
On the other hand, less dense material comes up as dark. The ventricles, for example, are filled with cerebrospinal fluid, which is mostly water. The ventricles often appear dark. If there were an enlargement of the ventricles, this could be observed easily on the CT scan. Also, bleeding out of the meninges can result in a darker patch underneath the skull surface, a sign that is easily observed in the scan.
Another advantage is that the CT is faster than many other methods of anatomical analysis. A complete scan of the brain might only take 10 minutes.