You can find answers to many of your questions on various reliable websites. The sites listed below can give you information for understanding your exam, but they are not a substitute for a doctor’s advice or diagnosis.
The ABR is a leader in advancing patient care by improving the professional standards of each radiologic site. ABR provides certifications for diagnostic radiologists, radiation oncologists and medical physicists.
This professional organization for radiologists provides information you may find useful. The link above will take you to a page with many downloadable brochures that explain procedures and help you understand the process of making and reading radiologic exams.
One of the most important rules in radiology is to limit the amount of radiation to which a patient is exposed during a radiology exam. You can learn more about imaging radiation and its risks on this website.
This U.S. government website provides information about many types of radiologic exams.