What is a Chest X-Ray?
The chest X-ray is the most common radiologic procedure. The X-ray is projected toward the chest to show the heart and lungs, bones and soft tissues. The actual time of the average X-ray exposure is extremely short -- often less than one-half second. Some of the radiation penetrates the part of the body being examined and thus creates the X-ray image.
To understand what happens when an X-ray is taken, a comparison can be made with the use of a camera in taking a photograph.
The X-ray exposes the film to form an image just as the light exposes the film inside a camera. The film in a camera is developed and used to make a photographic print or it is used directly as a slide. The X-ray film is also developed and viewed with transmitted light on a light box or computer screen.
The chest X-ray technique in young children involves two views. The initial view is from the front, and the second is a side view.
In young children, the patient lies on the table and the hands are held above the head.
In an older patient, the child stands upright for one image and then turns sideways for the second image. The technologist tries to focus the radiation beam using a light on the patient's chest. This reduces the amount of radiation to other parts of the body.
After taking the X-ray, the radiologist reviews the film. They can compare it with prior films, which is important when evaluating heart size and blood flow to the lungs. They share the results with the cardiologist and the referring doctor.
Preparing Your Child for a Chest X-Ray
A chest X-ray requires little or no advance preparation. Sometimes children are frightened by the large and unfamiliar equipment in the X-ray room; however, a simple explanation is often helpful, depending on the child's level of understanding.
Parents can stay with their child during the X-ray. When the image is about to be taken, parents are encouraged to remind the child to hold still so that the picture will be sharp and clear.
Occasionally, restraining the child is necessary to have an adequate film and reduce radiation exposure (by not repeating the study).
The technologist will work with parents to find the best way to work with their child.
Use of X-Rays in Managing Cardiac Problems
The most frequently ordered X-ray is the chest X-ray, which helps the doctor decide if the heart is big, if there is pneumonia, or if there is fluid in the lungs.
X-rays are also used during cardiac catheterizations, which allows the cardiologist to better understand the physiology of the heart, assess pressure measurements, identify sites of obstruction, and determine function.
In addition, interventional cardiology procedures use radiation to aid placement of catheters, coils, or other devices. The radiation exposure allows the cardiologist to "treat" non-operatively specific congenital heart abnormalities.
Safety of X-Rays
Radiation is not something just made in the hospital, and natural radiation far exceeds man-made sources of radiation.
Natural radiation exposure comes from the sun, from rocks and soil, and even within our own bodies from things we have eaten such as milk or water.
The radiation in food and drink comes from water, plants and animals, which receive radiation from the earth or the sun.
Medical X-rays account for only about 15 percent of the annual radiation exposure in the United States. This figure includes the radiation used in radiation therapy (high dose) and in nuclear medicine.
Depending upon the severity of a child's problem, the number and complexity of X-ray exams needed to diagnose and determine the extent of an illness vary.
Even with multiple and repeated chest X-ray exams or repeat cardiac catheterizations, the total dose is still small. The expected benefits of the X-rays must always outweigh any possible risk for the examination to be performed.
Efforts to Minimize Radiation Exposure
- X-rays are taken only on the recommendation of a qualified cardiologist or doctor. The doctor is able to balance the benefits of having the X-ray exam against the risk of causing any possible side effect.
- Personnel performing the test are comfortable dealing with children. The radiology and cardiology departments of Cincinnati Children's take great strides in having up-to-date equipment. Routine surveillance of equipment and fulfilling all state regulations for registration and maintenance of equipment are mandated, not only by the state health department Bureau of Radiation Safety, but also by the hospital. Annual inspections of the equipment and review of departmental procedures are always in compliance.
- All Cincinnati Children's personnel who use the equipment are trained and qualified for its use.
- All X-ray technologists are part of the National Registry for Radiologic Technologists.
- Also, doctors involved in performing X-ray procedures undergo specific training to reduce radiation exposure and use techniques that decrease exposure.