X-Ray Diagnostic Techniques
X-ray diagnostic imaging is one of the most important tools of modern medicine. Approximately 120,000 x-ray rooms are in use in the United States; an estimated 240 million x-ray procedures are performed in the United States every year. X-ray diagnostic imaging is based on the tissue-differential contrast generated by x-ray and tissue interaction. In Section 26.1 we discuss x-ray-tissue interaction and tissue contrast mechanism. In addition to the traditional coverage of x-ray attenuation-based tissue contrast, we discuss x-ray phase-based tissue contrast, which arises from the very nature of x-ray as a wave. Such coverage is especially appropriate in view of the recent surge of research efforts in x-ray phase imaging. X-ray generation, spectra, and exposure control are discussed in Section 26.2. Section 26.3 discusses projection x-ray imaging (radiography and fluoroscopy), digital imaging detectors and x-ray image intensifiers, and image signal-to-noise ratio analysis of projection imaging. In Section 26.4 we discuss in-line phase-contrast imaging, an emerging x-ray imaging modality with great potential for biomedical applications.