Introduction
Computed tomography (CT) and Radionuclide imaging (RNI) are both a form of diagnostic imaging. Since they have been first introduced in medical imaging they both suffered a huge development over the years in terms of image acquisition and also patient radiation protection. The following essay it is going to focus on just a few important things that make CT and RNI similar and different in the same time. However this subject can be discussed in much depth, the focus is going to be on the similarities and differences of the physics imaging methods and also a small awareness of biological effects and radiation protection.
As a starting point in CT diagnostic imaging the form of radiation used to provide an image are x-rays photons , this can also be called an external radiation dose which detect a pathological condition of an organ or tissue and therefore it is more organ specific. However the physics process can be described as the radiation passes through the body it is received by a detector and then integrated by a computer to obtain a cross-sectional image (axial). In this case the ability of a CT scanner is to create only axial two dimensional images using a mathematical algorithm for image reconstruction. In contrast in RNI the main property for producing a diagnostic image involves the administration of small amounts of radiotracers or usually called radiopharmaceutical drugs to the patient by injection or oral. Radio meaning the emitted of gamma rays and pharmaceutical represents the compound to which a nuclide is bounded or attached. Unlike CT has the ability to give information about the physiological function of a body system. The radiopharmaceutical often referred to as a nuclide has the ability to emit ga...
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...s in one direction to acquire a single image slice. For another slice to be imaged the x-ray tube would again rotate another 360 degrees but on opposite direction. However this has been changed over the years and has been implemented a Slip-Ring technology which replaced the old high tension cables. In this way the new CT scanner x-ray tube had the ability to rotate continuously around the patient and in the same time the table was moving through the gantry to acquire data in a form of a Spiral or Helical. Therefore the new generation of CT scanners is called Spiral or Helical CT. The advantages of the new scanners are that the volume data can be reconstructed in any other planes (sagittal, coronal and three dimensional images), also there is a short time scan therefore radiation to the patient is minimized and also the artefact caused by patient motion is reduced.
the effective doses from diagnostic CT procedures are typically estimated to be in the range of 1 to 10 mSv. This range is not much less than the lowest doses of 5 to 20 mSv estimated to have been received by some of the Japanese survivors of the atomic bombs. These survivors, who are estimated to have experienced doses slightly larger than those encountered in CT, have demonstrated a small but increased radiation-related excess relative risk for
The description of PET scans in detail requires the understanding of the radioactive substance injected into the subject. First, a small amount of a biochemical substance is tagged with a positron-emitting radioisotope. A positron is an “anti-electron.” Positrons are given off during the decay of the nuclei of the radioisotope. When the positron emitted collides with an electron in the tissue of the subject, both the positron and the electron are annihilated. When this happens, the collision produces two gamma rays having the same energy (511 KeV), but going in opposite directions.
Johnston, J. (2012). Essentials of Radiographic Physics and Imaging. St Loius, Missouri: Elsevier Mosby Publishing.
What is radiology? Radiology is a branch of medical science that makes the use of radiation and radioactive materials. Radiology is related to energy- related physical phenomena in the diagnosis and treatment of particular diseases. Two major therapy- related areas of radiology are so- called therapeutic radiology. Therapeutic radiology deals particularly with the use of ionizing radiation is to treat cancer, and interventional radiology, Which radiological imaging techniques are used to assist various minimally invasive surgical procedures.
Radiation is something that the naked eye cannot see, yet has the potential to save lives one treatment at a time or even one image at a time. Since the discovery of x-rays in 1895, it has branched out into numerous modalities each independently specializing in their own ways. X rays are used to aid in the diagnosis and treatments of patients on a case by case scenario. Sometimes doctors can make a diagnosis on the same day or conclude that a patient will require radiation therapy within weeks to follow. Whatever it may be, the importance of x rays and radiation itself is a crucial part of the medical field when it comes to saving lives. Initially it all started with the discovery of x rays but then three years later radiation therapy was introduced to aid with
Radiation is something that we are exposed to on a daily basis; it is in the air we breathe. Radiation is used in hospitals, research labs, and in many medical procedures. It is also commonly used as a treatment for cancer. In some cases it helps and in others it does not. Radiation is used for cancer treatment because it kills cells. The issue is that it is killing healthy cells at the same time it is killing cancerous cells. Even though medical imaging emits radiation, it makes it possible for us to detect injuries and significant diseases. Radiation is measured in a few different ways, and has numerous side effects on our body depending on the dosage. We are exposed to it in the environment unintentionally, and at times in treatment purposely. Additionally, there is current research in effort to reduce the amount of radiation in medical procedures.
Radiation therapists work closely with patients to fight cancer. According to Health Care Careers, Oncologists, Dosimetrists and nurses are some of the professionals that a radiation therapist works with while caring for a cancer patient. This group of professionals will determine a specialized treatment plan. The first step usually includes a CT scan performed by a radiologist to find the exact area that needs to be targeted with x-rays. Next, the therapist uses a special machine that emits radiation called a Linear Accelerator. They use this machine during a treatment called external beam therapy. During this process, the Linear Accelerator will project x-rays at targeted cancer cells or tumors. Another therapist will be in a different room monitoring the patient’s viral signs until the procedure is over. The external therapy l...
Marshall, G. W and S. Keene. “Radiation Safety in the Modern Radiology Department: A Growing Concern.” The Internet Journal of Radiology 5.2 2007: N. pag. 24 Apr. 2011 .
CT scans and MRIs, or are incorporated into them in a different way for a clearer picture of what is
This image portrays the first radiological advancement produced and expanded to the medical field. I say this because the radiological discovery created what is today known as imaging tests and/or diagnostic tests. X-rays are known to create a clear bone/skeletal transparency of the human body. Through time X-rays as well as other radiological techniques progress into a more useful resource for professionals. Although the discovery of the different types of ionizing radiation was historical and life changing in the life of science, the high levels of energy within that radiation process was also harmful. Many people/Medical Doctors were unaware that by having X-rays tested on them, they were exposing themselves to radiations sickness and even worse, cancer. After radiology was known to be dangerous, physicians and nuclear energy workers researched and found better ways to prevent the human body from being affected by the radiation. Since then, radiology has guided practitioners when trying to determine the location from where the disease began and how much the disease has spread since its initial state. “Use of highly conformal radiotherapy techniques has heightened the need for image-based verification of treatment delivery on a more frequent basis than just the weekly portal images” (Clinic Radiation Oncology chapter 6. Radiation Oncology Physics Pg.137). Radiation oncology has served as a form of
Radiology technology is a science of using radiation to produce images. There are many jobs you can perform in diagnostic imaging usually a radiologic technologist will oft...
An important change came about with the development and common use of computer technology. “Such use of a filmless radiology department was very interesting to this medical field. Digital radiography was introduced in the mid 1980’s and now competes with screen film radiography in all radiographic applications” (Bansal, 2006).
One of the most important concepts in healthcare is patient care. It is our responsibility as health professionals to provide the utmost care to each and every patient we come into contact with. This is especially important when it comes to radiology. As radiographers, we must abide by ASRT Code of Ethics and provide the patient with the best care while also minimizing the use of radiation when possible. Concepts such as shielding, ALARA, collimation, and techniques all play an important role in minimizing patient dose and providing protection to the patient. This section discusses many important concepts including the radiographer’s role in patient protection, methods to decrease exposure, methods of estimating dose, and patient dose pertaining
Before an imaging session the technologists prepares, maintains, and sterilizes the equipment. They also greet patients, explain the role of the procedure or treatment, and records the patient’s medical histories if they haven’t been completed before hand. Once the technologist reviews the radiologists test request or prescription to determine the type and extent of imaging, testing, or particular treatment required they begin by entering the appropriate scan sequence into the radiologic and magnetic imaging equipment. If the test requested requires a soft tissue exposure the technologist with then prepare a radiopaque solution for the patient to ingest or be placed as an enema prior to the examination. During the sessions, the technologist directs and positions the imaging equipment close to the patient’s body and creates the requested x-ray, video, or computerized images. While doing the procedure, the technologist must ensure patient comfort and safety through the entirety of the procedure. They also must be clear and precise when instructing the patient how and where to position their body all while following all the safety guidelines to limit the patient’s radiation exposure as well as for themselves and fellow
CTscans stands for “Computed Tomography”. It is a way of looking inside your body using a special camera. It is an advanced scanning x-ray and computer system that makes detailed pictures of horizontal cross-sections of the body, or the part of the body that is x-rayed. A CT scan is a diagnostic test that combines the use of x-ray with computer technology. A series of x-beams from many different angles are used to get these cross-sectional images of the patient’s body. In a computer, these pictures are assembled into a 3-dimentianal picture that can display organs, tissues, bones, and any such thing. It can even show ducts, blood vessels and tumors. One of the advantages of CT is that it clearly shows soft tissue structures (such as brain), as well as dense tissue structure (such as bone). The pictures of a Ctscanner are a lot more detailed than the pictures of a regular X-ray machine. It can make pictures of areas protected or surrounded by bones, which a regular X-ray machine can not. Because of this, a CT scanner is said to be 100 times as affective and clever as an ordinary X-ray, and can therefore diagnose some diseases a lot earlier and quicker. It is recent technology that has made it possible to accurately scan objects into a computer in three dimensions, even though the machines and ideas were developed in the 1970s. In the 70s doctors started to use this new type of machine that could give detailed pictures of organs that the older type of x-ray, machine could not give.