Since the discovery of the X-ray by Wilhelm Conrad Röntgen in 1895, vivo medical imaging technology has developed rapidly. With the advent of modern computers in the early 1970s, new tomographic imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) have been developed to deliver cross-sectional images of a patient's anatomy and physiology. The role of medical imaging is to demonstrate the existence or absence of pathology in the human body. IVA also cooperates with NIH in the research of medical imaging and image processing projects.