Jeffrey Klein MD - Brant and Helms’ Fundamentals of Diagnostic Radiology

Abbreviations for use throughout Klein/Brant/Helms/Vinson, Fundamentals of Diagnostic Radiology, 5th Edition.

WILLIAM E. BRANT

Diagnostic radiology is a dynamic specialty that continues to undergo rapid change with ongoing advancements in utilization and technology. Not only has the number of imaging methods increased, but each one continues to undergo improvement and refinement of its use in medical diagnosis. This chapter reviews the basics of the major diagnostic imaging methods and provides the basic principles of image interpretation for each method. Contrast agents commonly used in diagnostic radiology are discussed. The basics of nuclear radiology are discussed in later chapters.

Conventional radiographic examination of the human body dates back to the genesis of diagnostic radiology in 1895 when Wilhelm Roentgen produced the first x-ray film image of his wifes hand. Conventional radiography remains fundamental to the practice of diagnostic imaging.

Image Generation.X-rays are a form of radiant energy similar in many ways to visible light. X-rays differ from visible light in that they have a very short wavelength and are able to penetrate many substances that are opaque to light. The x-ray beam is produced by bombarding a tungsten target with an electron beam within an x-ray tube.

Film Radiography.Conventional film radiography utilizes a screen-film system within a film cassette as the x-ray detector. As x-rays pass through the human body they are attenuated by interaction with body tissues (absorption and scatter) and produce an image pattern on film that is recognizable as human anatomy. X-rays transmitted through the patient bombard a fluorescent particlecoated screen within the film cassette causing a photochemical interaction that emits light rays, which expose photographic film within the cassette ( ).

Computed radiography (CR)