The Physics of Medical Imaging

With so much of modern medicine depending on medical imaging, it is important for us to gain a basic understanding of how the technology works. From X-rays to MRIs, medical imaging plays an important role in both preventative and diagnostic medicine.

In this article, “The Essential Physics of Medical Imaging,” the researchers discuss how these images are produced. The paper delves deep into the science behind modern imaging technologies and gives insight into how these technologies were discovered. For example magnetic resonance imaging (MRI) hinges on the fact that hydrogen nuclei in the water molecules in our body will align themselves given a strong magnetic field. All atoms have a quantum mechanical property of spin. When the spin in an atom is not balanced internally, the nuclei have a non-zero spin and a magnetic moment. This magnetic moment will align in a magnetic field in a similar fashion as a compass aligns with the Earth’s field. By interpreting these signals, radiologists can form an image that is essentially a cross section of the region of interest. The images produced offer a stark contrast between the soft tissues and are extremely useful in parts of the body where soft tissue dominate such as the brain, the musculoskeletal and the cardiovascular system.

A basic understanding of this technology is essential for us to understand before delving into the issues, debates, and other related technologies of medical imaging. Imaging is a powerful advancement in biotechnology that helps us screen patients for various diseases and assess other disorders and injuries and factors heavily into government and private health care expenditures.