By Kathy Sinkin, RN, CDE
There are many types of x-rays. What your doctor is looking for will determine the type of x-ray that will be ordered for you. X-rays use a small amount of radiation which passes through your body to quickly capture an image inside your body. Dense objects such as bone block radiation, and appear white on the x-ray picture. They are used to look at teeth, joints (to diagnose arthritis), blocked blood vessels, chest and abdominal abnormalities. However, they don’t do well in showing muscles, tendons, or joints.
CT or CAT scan (Computed Axial Tomography) is a rapid (5-20 minutes) painless exam that combines numerous x-ray images from different angles. A computer can then produce cross-sectional views of the scans which show bones, soft tissues, and blood vessels inside your body. If needed, three-dimensional images of internal organs and structures of the body can be viewed. These can provide detailed images of bony structures or injuries, diagnose lung and chest problems, and detect cancers.
MRI (Magnetic Resonance Imaging) typically lasts from 30 minutes to one hour. It combines a powerful magnetic field and pulses of radio waves to produce accurate detailed pictures of the body such as the heart, blood vessels, tissues, bones, spinal column, brain, and other internal structures. There is no radiation exposure. The MRI scanner itself is a tube surrounded by a giant circular magnet. A patient lies on a moveable bed that is inserted into this magnet.
A special dye or contrast material is needed for some CAT scans and MRIs to help highlight the areas of the body being examined and give more detailed images.
Kathy Sinkin is a Registered Nurse and Certified Diabetes Educator with Cornell Cooperative Extension of Suffolk County’s Family Health and Wellness Program. She can be reached at kas239@cornell.edu