- 5 Medical Imaging Techniques
- Radiation Exposure Chart
- Ionizing Radiation Ill Effects
- Acute Radiation Syndrome
Accurate and timely diagnosis forms the foundation of early and effective treatment. Doctors use various blood tests and imaging techniques to diagnose health issues.
Imaging tests help the doctor see the inside of the body enabling them to diagnose and treat medical conditions more effectively. Some of these imaging tests use ionizing radiation, which means high energy radiation can remove an electron from an atom or molecule turning it into an ion.
Due to this effect, ionizing radiation, particularly above a certain dose, can cause ill effects on health.
Learn five medical imaging techniques that utilize ionizing radiation below.
5 medical imaging techniques that use ionizing radiation
- Radiography: They use X-rays to capture a single image of the body tissues for the diagnosis of health conditions. Mammography is a special type of radiography performed on the breasts. It is used to screen for breast cancer.
- Computed tomography scan (CT scan): A CT scan uses a higher radiation dosage than conventional radiography. It creates several images taken from various angles and tissue depths of the target site. The resultant images are of higher resolution and provide more detailed information than radiography.
- Angiography: It involves the examination of the blood vessels. In this technique, contrast is injected into a blood vessel and X-rays are used to ascertain the health of the blood vessels, such as an abnormal narrowing, blockage, or thickening of the blood vessels.
- Fluoroscopy: This procedure makes a real-time video of the movements inside a part of the body (such as the heart or gut) by passing X-rays through the body over a period. It can be used to diagnose diseases and guide during certain procedures (such as an implant or stent placement or injections into the joints or spine).
- PET-CT: This test combines a positron emission tomography (PET) scan and a CT scan. A PET scan uses a radioactive substance called a tracer to detect the metabolic or biochemical functioning of tissues or organs. It is a highly sensitive test and helps detect several health conditions (such as cancer and brain and heart conditions) quite earlier than a conventional CT scan.
How much radiation exposure occurs during medical imaging?
The radiation exposure varies according to the type of imaging technique. The exposure may differ from one lab to another depending on the type of equipment used and the modifications or settings are done (for example, many labs adjust the radiation dose at a lower level for children than adults).
To comprehend the amount of radiation exposure better, one must note that an average American is exposed to about 3 mSv of radiation from natural sources annually.
|Imaging study||Approximate radiation dose during a single exposure (in mSv)|
|Computed tomography (CT) scan (abdomen and pelvis)||10|
|Lower gastrointestinal (GI) series using X-rays of the large intestine||8|
|Positron emission tomography (PET)-CT||25|
|X-ray (lumbar spine)||1.5|
|Bone scan (nuclear imaging)||6.3|
What are the ill effects of ionizing radiations?
Ionizing radiations carry high energy and can damage the cells and tissues, leading to various health conditions. They are highly penetrating in the body and can damage the genetic material (DNA) of the cells besides causing other chemical changes in the cell.
The exposure can occur through natural (such as radon or cosmic rays in the environment) and manmade sources (such as during medical imaging or radiation therapy).
Exposure to ionizing radiation can result in various conditions, such as:
- Skin rashes or redness (erythema)
- Cancer (such as leukemia, lung cancer, breast cancer, liver cancer, multiple myeloma, ovarian cancer, and stomach cancer)
- Cataract (opacification of the eye lens)
- Infertility (temporary or permanent)
- Harm the unborn baby in case the woman is pregnant and undergoes radiographic imaging
- Genetic changes that may be passed on to future generations
Some imaging tests involve consuming a contrast or dye orally or administered through an intravenous line. Some people may develop an allergic reaction to the dye. Always inform your doctor if you have any known allergies before going for the test.
What is acute radiation syndrome?
Radiation exposure during medical imaging is generally kept at the lowest possible dose. The doctor ensures that the benefit of using the imaging test far outweighs the possible risk of radiation exposure.
Accidental exposure to a huge quantity of radiation can occur during situations, such as nuclear power plant accidents or the use of atomic weapons. Such heave and sudden exposure results in severe damage that may lead to serious skin and other tissue damage, acute radiation syndrome, and even death.
Acute radiation syndrome, also called radiation toxicity or acute radiation sickness, can damage various tissues, such as the bone marrow, gut, brain, and heart of the affected person. In severe cases, it can even cause the death of the person.
US Food and Drug Administration. Medical X-ray Imaging. https://www.fda.gov/radiation-emitting-products/medical-imaging/medical-x-ray-imaging
Dorfman AL, Fazel R, Einstein AJ, et al. Use of medical imaging procedures with ionizing radiation in children: a population-based study. Arch Pediatr Adolesc Med. 2011;165(5):458-464. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3686496/
Holmes EB. Ionizing Radiation and Medical Imaging. Medscape. https://emedicine.medscape.com/article/1464228-overview
Harvard Health Publishing. Radiation risk from medical imaging. https://www.health.harvard.edu/cancer/radiation-risk-from-medical-imaging
Top Medical Imaging Techniques and Ionizing Radiation Related Articles
Chest X-RayChest X-Ray is a type of X-Ray commonly used to detect abnormalities in the lungs. A chest X-ray can also detect some abnormalities in the heart, aorta, and the bones of the thoracic area. A chest X-ray can be used to define abnormalities of the lungs such as excessive fluid (fluid overload or pulmonary edema), fluid around the lung (pleural effusion), pneumonia, bronchitis, asthma, cysts, and cancers.
Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include:
- ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease.
- ARF: Acute renal (kidney) failure
- cap: Capsule.
- CPAP: Continuous positive airway pressure. A treatment for sleep apnea.
- DJD: Degenerative joint disease. Another term for osteoarthritis.
- DM: Diabetes mellitus. Type 1 and type 2 diabetes
- HA: Headache
- IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis
- JT: Joint
- N/V: Nausea or vomiting.
- p.o.: By mouth. From the Latin terminology per os.
- q.i.d.: Four times daily. As in taking a medicine four times daily.
- RA: Rheumatoid arthritis
- SOB: Shortness of breath.
- T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
CT Scan vs. MRI
CT scan (computerized tomography) is a procedure that uses X-rays to scan and take images of cross-sections of parts of the body. CT scan can help diagnose broken bones, tumors or lesions in areas of the body, blood clots in the brain, legs, and lung, and lung infections or diseases like pneumonia or emphysema.
MRI (magnetic resonance imaging) is a procedure that uses strong magnetic fields and radiofrequency energy to make images of parts of the body, particularly, the organs and soft tissues like tendons and cartilage.
Both CT and MRI are painless, however, MRI can be more bothersome to some individuals who are claustrophobic, or suffer from anxiety or panic disorders due to the enclosed space and noise, the machine makes.
MRI costs more than CT, while CT is a quicker and more comfortable test for the patient.
What Is the Difference Between a Bone Scan and a CT Scan?A bone scan and a computed tomography (CT) scan are both used to diagnose various bone conditions. The specific use of a bone scan is to diagnose active bone diseases, such as osteoporosis, Paget’s disease or the spread of cancer into the bone. A CT scan is a high-resolution X-ray that gives detailed information about organ anatomy.
How Is MRCP Different From MRI?MRCP is a subtype of an MRI scan that is better suited for detailed images of the pancreas, gallbladder, and bile ducts.
How Many Brazil Nuts Are Radiation Poisoning?Consuming two to three Brazil nuts per day is unlikely to pose a health risk; however, eating 50 or more nuts a day may cause radiation toxicity.
Is a Bone Scan the Same as an MRI?A bone scan is a nuclear imaging technology, whereas magnetic resonance imaging (MRI) uses magnetic waves to create a three-dimensional (3D) image of an organ. Therefore, they are different.
MRI (Magnetic Resonance Imaging Scan)MRI (or magnetic resonance imaging) scan is a radiology technique which uses magnetism, radio waves, and a computer to produce images of body structures. MRI scanning is painless and does not involve X-ray radiation. Patients with heart pacemakers, metal implants, or metal chips or clips in or around the eyes cannot be scanned with MRI because of the effect of the magnet.
What Are Examples of Medical Diagnosis?Medical diagnosis is the process of identifying a disease, condition, or injury based on the symptoms presented. Here are 5 of the most common diagnoses.
What Can Be Diagnosed With an Abdominal CT Scan?Learn four conditions that are diagnosed using an abdominal computed tomography (CT) scan.