A computed tomography (CT) scan, also known as a CAT scan, uses X-rays to make highly detailed pictures of the inside of the human body. A CT scan involves the patient laying down on mechanical table that is inserted into the CT machine. A scanner takes X-rays images and spins around the patient as the table moves into the machine, which is compiled into a cross sectional image. A CT scan can be used to study all parts of the body including organs, blood vessels, bones, chest, abdomen, extremities, and the spinal cord. A CT may be required in cases where the patient has a condition that prevents the use of an MRI such as a metal implant, shrapnel, pacemakers, etc.