Diagnostic imaging services are used to produce images of internal parts of the body. These images are used to diagnose illnesses, such as cancer, or abnormalities in body structure. Diagnostic imaging falls into either transmission, reflection, or nuclear emission imaging and is based on the technology and medical equipment used to create the image.
Diagnostic imaging services that use transmission imaging include x-ray and computed tomography (CT) scan. X-rays are taken by passing an electromagnetic beam through the body to produce the image. Bones will be white and muscles will be gray. All other tissues and organs will show as dark spaces.
A CT scan is a medical imaging process that uses x-rays and computers to show cross sections or slices of data. The data provides a more detailed picture of the body than an x-ray alone. These diagnostic imaging services are often used to discover brain injuries or tumors, and can also be used to examine other internal organs.
Reflection imaging is produced when high frequency sound waves are sent through the body. The sound waves bounce off tissues and organs at different speeds based on tissue density, and are tracked by computer programs. The sound waves are then put together to form a visual image.
Sonography imaging, also known as ultrasound imaging, is a well-known type of reflection imaging. Typically used for viewing images of unborn fetuses, ultrasounds can also be used to detect tumors in the liver or kidneys. Diagnostic imaging services that utilize sonograms can determine if there are obstructions in blood flow and whether reduced organ function is an issue.
Magnetic resonance imaging (MRI) is a type of nuclear emission imaging that involves magnetizing the protons in the body’s water molecules through a scanner. The result is a high-contrast resolution image that shows potential issues in the organs and soft tissues. Nuclear imaging is especially helpful at identifying problems with blood flow and the heart.
Another one of the diagnostic imaging services that employs nuclear emission imaging is positron emission tomography (PET). A small amount of radioactive material, called a radio-pharmaceutical, is injected or swallowed by the patient and then travels to the organs. As the material metabolizes, it emits gamma rays. The PET scan is able to detect the gamma ray emissions and convert the data into a computer image. The image is used to understand changes in both the function and structure of an organ, which can confirm irregularities.