X-rays in medicine
To understand X-rays, it is necessary to be familiar with the basics of transfer of energy.
Suppose an object needs to move from one position to another position, some force has to be applied in the direction of that motion. That force must be more than the resistance to motion, therefore, work will be done to overcome that resistive force. Energy is therefore the ability to do that work of moving that object against that resistive force. The energy used in this case could exist in many forms such as energy due to motion often referred to as kinetic energy or stored energy that can exist as potential energy. There are many other forms of energy such as chemical energy, electrical energy, etc.
These different forms of energy can be converted from one single form to another one single form or to multiple forms. For example, when an object in motion collides with another stationary object, sound energy, heat energy, and motion energies of a previously stationary object may result. The initial energy can not be lost at all but has basically re-emerged in a different way.
Suppose an energy needs to move from one point to another point for whatever reason, this process can be accomplished in two ways. One way is that the object which can be referred to as a particle can move from one location to a newer location and carry with it that same energy. The motion in this case requires a medium to transport the particle and its energy. The efficiency of the transportation of this energy will then depend on this medium.
The second method of accomplishing this task is to avoid the medium. The transportation system in this case would be a system that just oscillates in the direction of the motion and the energy follows the path of oscillation. The system that is capable of transferring energy from one position to another position in the manner does scribed above is called a wave.
For the waves to move in a vacuum, there has to be a force that pushes them through. These forces originate from electric and magnetic forces that are at perpendicular to each other. These forces are collectively called electromagnetic forces. Therefore the waves which move as a result of these electromagnetic forces and does work against these forces are called electromagnetic waves. All electromagnetic waves travel with the same speed as that of light.
X-rays are part of electromagnetic waves which differ from others based on their frequencies, that is, the number of oscillations per seconds and therefore they have their distinctive wavelength.
X-rays have very short wavelengths. With the same speed of light, they carry very high energy that can allow them to pass through very thick substances that normal light can not pass through. However, they will loose energy depending on the density of the material they are passing through and therefore leave an impression (contrast) that can be projected to a detector which can be an x-ray film. Those projections can be interpreted by experts.
Being energetic, X-rays deposit some of the energy and cause ionizations along their path. Since this energy arises (emitted) through the electromagnetic waves, X-rays are sometimes referred to as electromagnetic radiation or simply as radiation.
In the medical application, these contrast impressions are interpreted to discover any unusual deformity in a human being and therefore used as a diagnostic tool.
The medical sub specialty experts who use low energy x-rays to diagnose disease or deformity are referred to as radiologist.
The x-rays that carry extremely higher energies can be used to treat a disease. This therapeutic application of x-rays commonly used to treat cancer is typically referred to as radiation therapy. The medical sub specialty experts that use x-rays for this purpose are called radiation oncologists.
X-rays can not be seen. However, the presence of x-rays can be detected using specialized equipment designed to detect the amount and quality of X-rays. So a patient that is being exposed to radiation for the purposes of diagnostic or therapeutic will not see the radiation.
The issue with the fact that X-rays can not be seen makes it harder to know if the machine is actually producing the X-rays. Consequently, all machines used to produce X-rays are monitored regularly to assure their production and their quality.
If X-rays are not detected then that typically means that the X-rays are not being produced or the quality is questionable.
Contact us on how to perform the quality control (test the production or the quality of X-rays) of your medical equipment.
We will discuss the production of medical x-rays in the next blog.