Computed Tomography Technology
Robert Hays
Thomas Edison State College

Robert Hays
Current Trends and Applications in Applied Science and Technology
APS-401-OL011
June 2016

The technology that I have chosen to write about is one that I currently work with and am the most familiar with. In my occupation as a radiology technologist at Bassett Army Community Hospital, I am one of several soldiers who perform computed tomography (CT) scans for active duty soldiers, their family members, retirees and other beneficiaries within our footprint. Perform CT scans is an exciting and rewarding career path, and one that I am proud to be a part of. In this piece I will briefly discuss what this particular technology does and how it works, as well as delve into some of the benefits and disadvantages of CT scans.

CT is an interesting technology in terms of what it can be utilized for and how exactly it works. The technology used today owes it’s existence to the discovery of x-rays in 1895 by Mr. Wilhelm Roentgen. X-rays are a form of ionizing radiation. This type of radiation refers to the process by which an atom is excited, or energized to the point that outer layer electrons are expelled or “boiled” off. In CT, these electrons are directed towards a patient for the use of forming either a two or in some cases, three dimension image of the internal anatomical structures of the patient.

The specific concept of how a CT image is formed can be difficult to both explain and understand, although the overall process is much simpler to explain in comparison. Should a patient require a CT scan generally there are two different kinds from which to choose, contrast or non-contrast studies. The contrast is a liquid substance (ex. isovue, omipaque) that is either drank by the patient or injected directly into the veins. The substance in is radio dense, which means that when the ionizing radiation is directed into the patient in areas of the body where contrast is present, it will either absorbs the energy of the radiation or reflect it elsewhere to where it won’t be picked up on the image. This will show up white on the CT image, thus helping to visualize certain areas of the body that otherwise might not be well represented on a typical CT scan. Certain conditions or factors would rule out the use of contrast in a CT scan, but both contrast and non-contrast studies are performed relatively the same. The patients will lie still in one of several different positions on a table and then be slowly passed through the center of the CT machine, or gantry. This machine is shaped like a large donut, or simply a large circular object than the patient travels in and out of. As the patient travels through the machine, radiation is directed through their body in thin cross-sectional cuts. The radiation that makes it through is collected by a detector arrayed in a circular pattern around the patient and processed on a computer to form the images. The images can then be read and interpreted by a radiologist and other doctors to diagnose and treat any number of conditions or illnesses.

There are numerous benefits to CT scans. An obvious benefit to any and all imaging modality is the ability to noninvasively and often painlessly peer inside the body to assist in the diagnosis of disease and injury. Compared to other imaging modalities, CT imaging is one of the faster and more accurate methods for examining different parts of the body. The high number of cross-sectional images can create a high level of detail especially helpful when examining smaller parts of anatomy. CT is also helpful in accurately detecting the presence, size and location of unknown areas of tissue such as tumors and aiding in the biopsies used to test or remove such tissues. Some of the other excellent uses for CT scans are to detect the presence of broken bones, cancer, signs of heart disease and internal bleeding. In actuality, the benefits of CT scans are endless and it continues to evolve to this day

As with any good thing, while there are numerous benefits to this technology there are a few drawbacks as well. The use of ionizing radiation, while useful as a medical tool, has the potential to cause damage to DNA. This means that the radiation used in CT scans has the potential to mutate, or change the cells inside someone’s body to the point that certain cancers could develop as a result. The risk is small, but is always present. Another potential, albeit less harmful result of a CT scan could be an allergic reaction to the contrast material used. Again, this result is rare but is an ever-present risk associated with the use of CT scans and must relayed to all patients. While these complications seem less than desired, the benefits that can be gained from CT scanning often greatly outweigh any risks involved. Of course, there are certain steps that can be taken to reduce the two risks described such as the use of lead shielding and proper screening techniques to identify potential reactions to contrast material.

This concludes my brief overview of computed tomography scanning, a technology within my occupation I work closely with. I have detailed a basic idea of what CT can be used for and a general idea of how its inner workings. As well, some benefits and disadvantages of this technology were discussed as well. It was my hope that in doing so I have made you the reader better informed on this particular topic and increased your knowledge of its merits.

Sources

Medical X-ray Imaging. (n.d.). Retrieved July 02, 2016, from http://fda.gov/Radiation- EmittingProducts/RadiationEmittingProductsandPtocedures/MedicalImaging/Med icalX-rays/default.htm

CT Scans: MedlinePlus. (n.d.). Retrieved July 02, 2016, from https://www.nlm.nih.gov/medlineplus/ctscans.html

Computed Tomography (CT) - Body. (n.d.). Retrieved July 02, 2016, from http://www.radiologyinfo.org/en/info.cfm?pg=bodyct

Wilhelm Conrad Rontgen - Biographical. (n.d.). Retrieved July 02, 2016, form http://www.nobelprize.org/nobel_prizes/physics/laureates/1901/rontgen-bio.html