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We need chest x-ray to exam our body sometime, and as we know, it help doctors to diagnose patients’ parts of body, but what is chest x-ray? The radiologist explains to us.
The chest x-ray is the most commonly performed diagnostic medical x-ray examination. A chest x-ray makes images of the heart, lungs, airways, blood vessels and the bones of the spine and chest. An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
Some common uses of the procedure
The chest x-ray is performed to evaluate the lungs, heart and chest wall. A chest x-ray is typically the first imaging test used to help diagnose symptoms such as: shortness of breath, a bad or persistent cough, chest pain or injury, fever. Physicians use the examination to help diagnose or monitor treatment for conditions such as: pneumonia, heart failure and other heart problems, emphysema, lung cancer, line and tube placement, other medical conditions.
How does the procedure work
X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, a medical x-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special digital image recording plate.
Different parts of the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air appears black.
On a chest x-ray, the ribs and spine will absorb much of the radiation and appear white or light gray on the image. Lung tissue absorbs little radiation and will appear dark on the image.
Until recently, x-ray images were maintained as hard film copy (much like a photographic negative). Today, most images are digital files that are stored electronically. These stored images are easily accessible and are frequently compared to current x-ray images for diagnosis and disease management.
Limitations of Chest x-ray
The chest x-ray is a very useful examination, but it has limitations. Because some conditions of the chest cannot be detected on a conventional chest x-ray image, this examination cannot necessarily rule out all problems in the chest. For example, small cancers may not show up on a chest x-ray. A blood clot in the lungs, a condition called a pulmonary embolism, cannot be seen on chest x-rays.
Further imaging studies may be necessary to clarify the results of a chest x-ray or to look for abnormalities not visible on the chest x-ray.
The benefits vs. risks of chest x-ray
Benefits
1. No radiation remains in a patient's body after an x-ray examination.
2. X-rays usually have no side effects in the diagnostic range.
3. X-ray equipment is relatively inexpensive and widely available in emergency rooms, physician offices, ambulatory care centers, nursing homes and other locations, making it convenient for both patients and physicians.
4. Because x-ray imaging is fast and easy, it is particularly useful in emergency diagnosis and treatment.
Risks
1. There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk.
2. The chest x-ray is one of the lowest radiation exposure medical examinations performed today. 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.
3. Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant.

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