What is a chest X-ray? What is the main examination of chest X-ray? What's the difference between chest X-ray and chest X-ray? How much does it cost to have a chest X-ray?

Chest radiography, called fluoroscopy, is a common X-ray examination method. It uses the characteristics of X-ray's penetrability, fluorescence and photographic effect to make the human body form an image on the screen. Due to the difference in density and thickness of human tissues, when X-rays penetrate different tissues, the absorption degree of X-rays is different, so the amount of X-rays reaching the screen is also different, forming a black-and-white contrast image, which provides a basis for doctors' diagnosis.

Purpose of chest x-ray

Mainly to see if there is any abnormality in the heart, liver and lungs, and the most important thing is to find tuberculosis.

bioeffect

The health hazard of radiation to human beings comes from the changes of atoms and molecules composed of atoms in tissues and cells caused by various rays through ionization. α and β particles are knocked out after directly colliding with electrons in atoms. The ionizing radiation caused by X-rays and neutrons is caused by the secondary charged particles produced by their interaction with matter, which is called secondary ionization. Ionization is due to the penetrating radiation of high-energy particles, so that electrons in atoms are expelled. It mainly damages cells by acting on DNA molecules, resulting in various health hazards. The energy deposition of ionizing radiation on tissues and organs is a random process. Even at a relatively low dose level, if energy is deposited in the key target area of cells, it will lead to changes or death of cells. However, if the X-ray radiation is within the allowable range, the impact is generally small. The use of high kV technology, image enhancement technology, high-speed intensifying screen and fast X-ray photographic film significantly reduces X-ray radiation and the possibility of radiation damage.

Chest X-ray examination has the largest radiation, and one chest X-ray examination is equivalent to taking 10 X-rays. Half an hour later, the chest X-ray can show that the chromosome aberration rate and micronucleus rate increase after the DNA damage caused by X-ray is wrongly repaired. X-rays acting on the erythrocyte membrane may reduce the number of charges and the activity of enzymes on the membrane, thus reducing the ability of C3b receptors on the erythrocyte membrane to remove pathogenic immune complexes, and also causing changes in glycogen metabolism of lymphocytes. There is a statistical random effect between low-dose nuclear radiation carcinogenesis and genetic diseases, and its severity is not affected by absorbed dose, but the carcinogenic probability is related to dose, and there is no dose threshold. According to the latest research results of the International Commission on Radiological Protection, it is estimated that in a city with a population of about 6.5438+million, about 350 people may be induced by X-ray irradiation every year to have cancer, leukemia or other hereditary diseases.

X-ray examination is a double-edged sword. X-ray is harmful to human body, but many diseases can't be diagnosed without it. Among all X-ray examination methods, the harm of chest X-ray is very clear, and developed countries such as the United States and Japan have basically eliminated this method. A few countries that still use this method try their best to reduce the utilization rate. For example, in Britain, the usage rate is only 0.2%, and it is required to shield the non-examined parts, especially the gonads and thyroid gland. If the doctor is negligent, his radiation license may be revoked. In China's relevant laws and regulations, it has long been stipulated to limit and reduce the harm of X-ray chest photography to human body, such as "X-ray fluoroscopy should be avoided in the screening and general survey of X-ray diagnosis" and "X-ray fluoroscopy should not be used as a routine examination item for children and adolescents" in the Basic Standards for the Safety of Ionizing Radiation and Radiation Sources. "Medical X-ray diagnostic radiation health protection and image quality assurance management regulations" stipulates that "the routine examination items of infants and adolescents shall not be included in X-ray chest examination; Before employment or regular physical examination, the interval of chest X-ray examination is generally not less than two years. " Unfortunately, the probability of using X-ray chest radiography in China is very high. In many places, it has become a "reserved program" in the annual entrance examination, entrance examination, employment examination and unit health examination!

chest radiograph

Chest X-ray is chest X-ray, which is called chest X-ray clinically. Chest radiography is more and more widely used in clinic, and people's understanding is getting deeper and deeper, so

Subjects take a standing posture and generally hold their breath under calm inhalation. Conventional chest X-ray examination of cardiovascular system includes anteroposterior position (focal distance is 200cm), left anteroposterior position (60 ~ 65), right anteroposterior position (45 ~ 55) and left lateral position photos. Chest X-ray can show the size, shape, position and outline of the great vessels of the heart, observe the relationship between the heart and adjacent organs and the changes of pulmonary vessels, and can be used to measure the heart and its diameter. The left anterior oblique film shows the whole picture of aorta and the enlargement of left and right ventricles and right atrium. The right anterior oblique radiograph is helpful to observe the changes of left atrial enlargement, pulmonary artery segment protrusion and right ventricular funnel enlargement. The left X-ray film can observe the anterior and posterior diameter of the heart, chest and thoracic malformation, which is particularly important for the differentiation and location of aortic aneurysm and mediastinal tumor.

general situation

X-rays pass through the chest and are projected onto the film to form a chest film. X-rays are harmful to the body-it may cause cancer and so on. And it may cause malformation to the fetus. So it should be

Reduce contact. It can be shielded by a few millimeters of lead plate, and it is best to avoid it from a long distance-dozens of meters away.

Compared with chest X-ray, chest X-ray images are clear and have good contrast, which is suitable for observing subtle lesions and thick parts, and records can be kept permanently for comparison and consultation. This is also the reason why doctors advise patients to take chest radiographs after finding lesions in chest radiographs. The disadvantage of chest radiograph is that it can't observe the movement of active organs, which is expensive and takes a long time to produce results.

Chest radiography

Chest radiographs are often used to examine chest diseases (including ribs, thoracic vertebrae, soft tissues, etc. ), chest, lung tissue, mediastinum, heart, etc. Such as pneumonia, tumor, fracture, pneumothorax, cor pulmonale and heart disease.

Check content

General chest X-ray examination can take head X-ray, chest X-ray, abdominal plain film and limb joint X-ray.

1. Chest X-ray can observe lung, pleura, mediastinum and heart, great vascular diseases, fractures and joint dislocation of limbs.

2. It can be used for the diagnosis of opaque foreign bodies in soft tissues, esophagus and gastrointestinal tract of limbs.

3. Abdominal plain film can tell whether there is pneumoperitoneum and intestinal obstruction after gastrointestinal perforation.

Pneumonia of both lungs

Check the tumor

Check cracks

Check pneumothorax

Check pulmonary heart disease

Check the heart

Chest radiography

X-ray chest film, commonly known as "filming", is also listed as one of the routine physical examination items. X-ray photography has become the first choice for chest examination because of its rapid, simple and economical advantages.

The characteristics of X-ray chest film X-ray chest film can clearly record the general lung diseases, such as lung inflammation, mass, tuberculosis and so on. X-ray films can observe the lesions in parts with little difference in thickness and density by using the different densities of human tissues. Compared with chest fluoroscopy, X-ray chest film is clearer and can find subtle lesions. The objective record of image data is conducive to the review and comparison of disease diagnosis and treatment; The radiation dose received by patients undergoing fluoroscopy is also relatively large.

Although the examination is excellent, it is an indisputable fact that overclocking radiation is harmful to human body, and X-ray is a double-edged sword for human health. According to the standards formulated by the International Commission on Radiological Protection, the total radiation risk is 0.0 165/ sievert, while the chest X-ray takes less than half a second, and the exposure rate is about 0.045 millisieverts/second (1 sievert = 1000 millisieverts), which is very limited to human health risk. However, the gonads, lenses, mammary glands and thyroid glands in the human body are particularly sensitive to radiation, and too frequent examination is not beneficial.

Precautions ① Special people, including infants and pregnant women (especially in the first three months of pregnancy), should be careful about X-ray examination and make necessary protection. (2) Except for invigilators, other personnel should not stay in the examination room for a long time. ③ Don't put coins or mobile phones in the inspector's chest pocket; Take off necklaces, mascots and other ornaments around your neck; Female patients please take off their bras with metal brackets and clothes with buttons. (4) Carry the latest imaging data with you during follow-up so that doctors can make diagnosis and treatment according to the condition.