What is Chest Radiography?
Chest x-ray is the most commonly performed diagnostic x-ray examination. Approximately half of all x-rays obtained in medical institutions are chest x-rays. A chest x-ray is usually done for the evaluation of lungs, heart and chest wall. Pneumonia, heart failure, emphysema, lung cancer and other medical conditions can be diagnosed or suspected on a chest x-ray. Traditionally, chest x-rays have been taken prior to employment, prior to surgery or during immigration.
What are some common uses of the procedure?
Chest x-ray is typically performed as the first imaging test for symptoms of shortness of breath, a bad or persistent cough, chest pain, chest injury or fever. Individuals with known or suspected medical conditions such as congestive heart failure or cancer may have chest x-rays to follow their response to treatment, or to determine changes that would require a change in their medical management.
How should I prepare for the procedure?
What does the x-ray equipment look like?
How does the procedure work?
How is the procedure performed?
Next, the technologist walks into a cubicle or small room to activate the radiographic equipment, which sends a beam of x-rays from the x-ray source behind the patient, through the patient’s chest, to the recording medium.
The technologist may need to take additional views to properly see all parts of the chest or may take a side view, or lateral view, of the chest. For a lateral view, the patient stands sideways to the photographic plate with arms elevated, and the process is repeated. Views from other angles may be obtained if the radiologist needs to evaluate additional areas of the chest. Finally, a chest x-ray may be repeated within hours, days or months to evaluate for any changes. These repeated, sequential examinations are called serial chest x-rays.
When the chest x-rays are completed you will be asked to wait until the technologist checks the images for motion and makes sure that the entire chest is included. Ultimately, a radiologist will interpret the chest x-ray images.
What will I experience during the x-ray procedure?
Who interprets the results and how do I get them?
A radiologist (a physician specifically trained to supervise and interpret radiology examinations) will analyze the images and send a signed report with his or her interpretation to your primary care physician or other health care provider who will inform you of your test results.
What are the benefits vs. risks?
- A physician may recommend a chest x-ray for a patient with shortness of breath, a bad or persistent cough, chest pain or a chest injury. In the instances of pneumonia, the site of pneumonia and fluid in the lungs will appear white on the image.
- A chest x-ray may also show advanced emphysema as well as other diffuse lung conditions, such as pulmonary fibrosis.
- Lung cancers and tumours that spread to the lung may be visible on chest x-ray. However, lesions that are very small or superimposed on normal structures may not always be visible.
- Heart enlargements caused by fluid around the heart (pericardial effusion), heart muscle disease, abnormal heart anatomy or congestive heart failure may also be visible on a chest x-ray depending on their severity.
- Pleural effusions (fluid around the lungs) on one or both sides can be detected. Usually the cause of such fluid may be deduced from clinical data or other findings on the chest x-ray; however, it may be necessary to sample the fluid to determine its nature.
- X-rays are a type of electromagnetic radiation, are invisible and create no sensation when they pass through the body. The chest x-ray is one of the lowest radiation exposure medical examinations performed today.
- Special care is taken during chest x-ray examinations to ensure maximum safety for the patient by paying attention to correct x-ray beam energies. Shielding the abdomen and pelvis with a lead apron helps reduce unnecessary radiation to the abdomen and pelvis. Women should always inform their doctor or x-ray technologist if there is any possibility that they are pregnant.
- The effective radiation dose from this procedure is about 0.1 mSv, which is about the same as the average person receives from background radiation in 10 days.
What are the limitations of Chest Radiography?
A chest CT may be requested to further clarify a finding seen on the chest x-ray or to look for an abnormality not visible on a chest x-ray in order to answer the clinical problem. The degree of involvement of the lung, as well as the distribution of disease, and anatomic location may be better evaluated with chest CT, helping aid the diagnosis. Some diseases, such as chronic lung disease, are frequently evaluated with HRCT (high-resolution CT).
The chest x-ray and the physical examination should be correlated. The information each procedure provides can give the physician a clearer understanding of the patient’s health.