CT Scanner
A CT scan is commonly used when looking for irregularities in tissue, including tumors, growths and internal bleeding, and bone fractures. A CT scan can be used to track the progress of cancer and heart disease treatments as well. A low-dose CT scanner is also an excellent preventative diagnostic tool that can capture images of early heart disease, lung disease, colon cancer and other problems before they become more serious health issues.
MRI
An MRI is used when highly detailed images are needed in a specific area of soft tissues. It is often used to diagnose serious issues in the brain, spine, ligaments, reproductive system and other internal organs. Based on your symptoms, your doctor will choose between an MRI or CT scan. However, an MRI is not generally used for preventative diagnostic measures because it takes longer and is more expensive to operate.