Present day technological developments in imaging and vision have brought so many changes in the medical diagnosis, treatment planning and treatment verification procedures. The accurate precision, speed in diagnosis process and non-invasive clinical procedures are drastically improved. In modern medicine, medical imaging has undergone major advancements. Today, this ability to achieve information about the human body has many useful clinical applications. Over the years, different sorts of medical imaging have been developed, each with their own advantages and disadvantages.
Overview of Medical Imaging
Aside from Superman with his x-ray vision, people generally can’t look at a sick person and instantly figure out the problem. Most medical issues occur inside the body, so making a diagnosis can be a challenge. Medical imaging has made that challenge far easier over the last century. Medical imaging is the technique of producing visual representations of areas inside the human body to diagnose medical problems and monitor treatment. It has had a huge impact on public health.
Medical imaging is the visualization of body parts, tissues, or organs, for use in clinical diagnosis, treatment and disease monitoring. Imaging techniques encompass the fields of radiology, nuclear medicine and optical imaging and image-guided intervention. Medical imaging refers to several different technologies that are used to view the human body in order to diagnose, monitor, or treat medical conditions. Each type of technology gives different information about the area of the body being studied or treated, related to possible disease, injury, or the effectiveness of medical treatment.
Medical imaging technologies are widely used in clinical diagnosis to guide therapeutic and surgical intervention and to monitor disease progression, recurrence and treatment response and to improve surgical navigation.
Types of Medical Imaging
There are many types of medical imaging, and more methods for imaging are being invented as technology advances. The main types of imaging used in modern medicine are radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound.
Radiography uses electromagnetic radiation to take images of the inside of the body. The most well-known and common form of radiography is x-ray. For this procedure, an x-ray machine beams high-energy waves onto the body. The soft tissues, such as skin and organs, do not absorb these waves, whereas hard tissues like bones do absorb the waves. The machine transfers the results of the x-ray onto a film, showing the parts of the body that absorbed the waves (the bones) in white and leaving the unabsorbed materials in black.
Figure 1: Body X-Ray
Magnetic resonance imaging involves radio waves and magnetic fields to look at the organs and other structures in the body. The procedure requires an MRI scanner, which is, simply put, a large tube that contains a massive circular magnet. This magnet creates a powerful magnetic field that aligns the protons of hydrogen atoms in the body. Those protons are then exposed to radio waves, causing the protons to rotate. When the radio waves are turned off, the protons relax and realign themselves, emitting radio waves in the recovery process that can be detected by the machine to create an image.
Figure 2: MRI Scanner
Nuclear medicine is a rather general term that involves any medical use of radioactive materials. But in terms of imaging, it usually refers to the use of radioactive tracers, which are radioactive materials that are injected or swallowed so that they can travel through the digestive or circulatory system. The radiation produced by the material can then be detected to create an image of those systems.
Figure 3: Nuclear Medicine
Ultrasound utilizes high-frequency sound waves, which are reflected off tissue to create images of organs, muscles, joints, and other soft tissues. It’s kind of like shining a light on the inside of the body, except that this light travels through the skin layers and can only be viewed using electronic sensors.
Figure 4: Ultrasound
 David Wood “Chapter 8/Lesson 7: Medical Imaging Techniques: Types & Uses”, available online at: http://study.com/academy/lesson/medical-imaging-techniques-types-uses.html
 Suetens, Paul, Fundamentals of medical imaging, Cambridge University press, 2017.
 G. Anil Kumar and Nistala V. E. S. Murthy, “Analysis of Medical Image Processing and its Applications in Healthcare Industry”, International .Journal of Computer Technology & Applications, Volume 5, Issue 3, pp. 851-860