Is it true that MRI, X -ray, CT and fluorography are dangerous to health?

Many believe that some medical studies are harmful to health and can themselves cause various diseases. We decided to check if these fears are justified. 

Users who have been assigned a study using MRI, They ask, is it not dangerous, on sites services questions and answers. On forums People share stories that they were not recommended to undergo an MRI due to possible harm. Even more likely questions Causes the procedure radiography -Internet users are often Interestedhow harmful it is and how often you can go through it, divided His fears before research. As for computed tomography, it scare Even doctors. For example, Alexander Myasnikov declaredthat one of the 500 children undergoing this procedure forms a brain tumor. 

Magnetic resonance tomography (MRI)

MRI Today is one of the most effective methods of medical research. The MRI apparatus is a large tube with powerful magnets, under the influence of which protons in the patient’s body are built in a certain order. Then, in the examined areas of the body, short bursts of radio waves are sent, knocking protons out of balance. When the radio waves turn off, the protons are rebuilt again. Special receivers catch their movement - this helps to obtain information about the exact location of protons in the body and, as a result, the exact picture of the structure of the human internal organs. Protons in different types of tissues are rebuilt at different speeds and produce different signals, so the receivers are able to distinguish, for example, bones from muscles. In the MRI procedure, unlike an X -ray, radiation radiation is not used, so from this point of view the procedure is absolutely safe.

Since powerful magnets are involved in the study, before the procedure it is necessary to remove everything Metal objects. If the patient’s body has any metal-containing implants (for example, pacemakers, some types of prostheses, pins or plates) or other objects such as bullets or fragments that cannot be removed, the MRI procedure can lead to serious injuries. This is one of the contraindications for the study.

In some cases, to obtain more accurate information during an MRI, the patient is intravenously introduced by the so -called Contrast substance, which can cause an allergic reaction. It is also not recommended for severe renal impairment, since the gadolinium contained in some contrasting substances can provoke the development of nephrogenic systemic fibrosis - a disease that leads to damage to internal organs. Nevertheless, experts note that all these side effects of the use of contrasting substances are very unlikely. 

Do not recommend using contrasting substances and during pregnancy, since the gadolinium Increases The risk of infant mortality and pathologies of fetal development. As for the MRI without a contrast matter, there is no confirmed data on the negative impact of this procedure on a pregnant woman and a child. Nevertheless, this question I have not yet been so well studied, and in order to answer the question of how safe it is, additional studies are needed.

In general, authoritative medical organizations, such as National Health Service Great Britain, University of Stanford (USA) and National Health Consulting Service Australia, MRI is considered a completely safe procedure.

Thus, the MRI procedure has several contraindications. The main of them is the presence of metal objects in the body that cannot be removed (for example, stuck fragments or pacemaker). Using an MRI, in these cases you can get serious injuries, since powerful magnets in the apparatus will attract the entire metal. Contrast substances, sometimes used to increase the accuracy of diagnosis, can cause an allergic reaction. They cannot be administered to patients with strong renal failure and should be used with caution during pregnancy. Moreover, in the absence of contraindications, experts call MRI a completely safe procedure that does not have any irreversible effects on human health.

Most of the untruth

X -ray

X -ray Allows you to get a black and white image of the internal structure of a person due to the effects of electromagnetic radiation radiation. Different fabrics absorb different amounts of radiation, and this affects the image in the picture: bones that absorb the most look white, fat and muscles - gray, and lungs with black. 

With the word “radiation”, people usually scare, recalling the Chernobyl accident or bombing of Hiroshima and Nagasaki, but natural Radiation background It is present in the environment constantly and it is impossible to avoid its impact. For example, c USA On average, a person receives from natural sources about 6.2 mZV. In Russia in 2020, this indicator There were about 4.18 mZv. If we compare the effects of an X -ray with this background, then the study of the chest comparable at the resulting dose of radiation with natural exposure for about ten days. And this dose is still three times lower than the one Get it Passengers of long -range flights.

The radiation dose also depends on which part of the body is subjected to research. So, for example, specialists of the American Dental Association They sayWhat, taking a picture of the jaw, patients receive a much smaller amount of radiation compared to daily natural effects.

At the same time, too frequent radiological studies can really harm health. That is why doctors Recommended Fix such studies in the medical card of patients in order to compare the need for x -ray and possible harm from it. Experts note that X -ray can really provoke the development of cancer in the long term, but this risk extremely small and again depends on the study. So, for example, an X -ray of the arm or leg can provoke cancer in only one person from a million, but the lumbar spine in one of 15,000. At the same time, use Baria - a contrast medium that allows you to explore on an X -ray, for example, the abdominal cavity, - seriously increases these risks. However, proven Increase The risk of cancer develops only when receiving a dose of 100 mZv per year.

Thus, if you carry out an X -ray only if necessary - for example, with fractures or in the treatment of teeth - the risk of health is minimal. Potential harm depends on the study of the study, some of them are comparable to the degree of irradiation with a natural radiation background received by people daily from the environment. In addition, usually during this type of research, doctors use lead aprons to protect other parts of the body from irradiation, which also reduces harmful effects. Moreover, some types of exposure, especially using barium -based solutions, can really increase the likelihood of cancer, albeit slightly. 

Half truth

Computed tomography (CT)

Ct - This is a more perfect type of radiological study using many rays, which under different angles pass through the examined organ and allow you to get a more detailed image. Accordingly, all the risks of X -ray associated with radiation are fair for CT. In this case, the radiation dose that the patient receives in such a study is much higher than with a conventional X -ray. So, for example, during the CT of the abdominal cavity, a person Gets An impact equal to four and a half years of life in a natural radiation background (with an ordinary X -ray - about four months). Accordingly, the risk of developing cancer due to such a study is higher: it can develop in one person out of 2000. 

Thus, unlike x -rays, the risks of developing cancer in the long term from the use of CT are much higher. However, diagnostics using this technology is more precise. Therefore, doctors in each case decide on the appropriateness of conducting a particular study, weighing risks and potential benefits. 

Half truth

Fluorography

Fluorography - Another type of radiological examination used, in particular, to detect tuberculosis and other pulmonary diseases. 

In Russia, fluorography is included in the protocol medical examination, which doctors advise to take place regularly. However, in 1974 He called To abandon the mass regular radiological examination due to the fact that the percentage of detected patients with tuberculosis or other diseases using this method is too small. 

At the same time and dose The radiation obtained in the fluorography of the chest is small - only about 0.5 mZV during film shooting and 0.05 mZV with digital. This is comparable in the degree of effect on the body with the usual x -ray, which has already been mentioned above. Although theoretically fluorography, like other studies using radiation radiation, can increase the risk of cancer, and experts do not consider this danger significant.

Thus, although fluorography, along with the X -ray, subjects the human body to radiation radiation and this is not useful, the effect on health it has a slight one. At the same time, in some countries, including in Russia, fluorography is included in the medical record and it is recommended to be held regularly. However, WHO experts recommend abandoning this practice, because the benefit does not exceed theoretical harm and costs of conducting such studies. 

Half truth

What do our verdicts mean?

Photo on the cover: Anna shvets, pexels.com

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