One of the more advanced ways that medical professionals use mathematics is in the use of CAT scans.  A CAT scan is a special type of x-ray called a Computerized Axial Tomography Scan.  A regular x-ray can only provide a two-dimensional view of a particular part of the body.  Then, if a smaller bone is hidden between the x-ray machine and a larger bone, the smaller bone cannot be seen.  It is like a shadow.

Image reproduced with permission of NeuroCognition Laboratory

It is much more beneficial to see a three dimensional representation of the body’s organs, particularly the brain.  CAT scans allow doctors to see inside the brain, or another body organ, with a three dimensional image.  In a CAT scan, the x-ray machine moves around the body scanning the brain (or whichever body part is being scanned) from hundreds of different angles.  Then, a computer takes all the scans together and creates a three dimensional image.  Each time the x-ray machine makes a full revolution around the brain, the machine is producing an image of a thin slice of the brain, starting at the top of the head and moving down toward the neck.  The three-dimensional view created by the CAT scan provides much more information to doctors that a simple two-dimensional x-ray.