Fluorography (FLG) or X-ray fluorography is a type of X-ray examination. It consists in photographing organs and tissues on film from a fluorescent screen and displaying the image on a monitor or image. The method is based on the fact that the density of various organs (heart, blood vessels, lungs) is not the same, therefore, when X-rays pass through them, negatives are obtained - dark and light areas. The process resembles photography and is projected onto film. Another name for FLG is radio photography.
The air cavity is shown in black, the bones are white, and the soft tissues are in different shades of gray. The results of the received picture are processed on the computer to give a conclusion. The radiation dose for fluorography of the lungs with such a survey is equal to that which a person will receive when using home appliances at home for 2 weeks.
The concept of X-rays
This is the electromagnetic radiation of ionized particles, located in the spectrum between gamma and ultraviolet. It is the basis for the diagnosis of many diseases. X-rays are unique in that they are neither refracted nor reflected. The radiation dose for fluorography corresponds to a continuous week of exposure to the sun.
Is there any harm from X-rays for the body
Many patients are concerned about the negative impact of x-rays on the body. When passing through the human body, the rays ionize it. Tissues and organs absorb them to varying degrees, then they talk about their susceptibility. At the same time, the structure of molecules, atoms changes - they are simply charged. This can lead to somatic disorders, in women - genetic disorders of the offspring.
X-ray affects organs in different ways. To account for such manifestations, there is a concept - the radiation risk coefficient for the corresponding organ or tissue. It determines the likelihood of harm occurring after radiation. A high coefficient is a high tissue susceptibility. And, consequently, the damage from radiation is also higher. The most susceptible are the hematopoietic organs, especially the red bone marrow. Therefore, in this system, pathologies arise in the first place. With little exposure, they are reversible; with more - there is a breakdown of erythrocytes and hemoglobin.
May be leukemia, erythrocytopenia, leading to organ hypoxia, decreased platelets. The cells of the outer layer of the vessel wall are also damaged.
Lungs, heart and nerves of an adult are fairly radio-resistant. Children and adolescents have not yet completed their development and their cells are actively dividing, so the mutational effect of X-rays increases in them. Fluorography is allowed only from the age of 15. Also, the procedure is not done for pregnant and lactating women.
Other possible pathologies:
- development of oncology;
- early aging;
- cataract with damage to the lens of the eye.
And what about in practice? In medical equipment, a beam of short duration and energy is used, therefore, even with repeated exposure during examinations, there is no harm to the body. For example, a single exposure to radiography will increase the risk of cancer in the distant future by only 0.001%. Judge for yourself if this is a lot.
Radioactive rays cease to operate after the device is turned off immediately. Why? Because they are electromagnetic waves, in fact. They do not accumulate, do not form other radioactive substances that could be sources of self-radiation.
Conclusion: There is no need to take drastic measures to reduce radiation after an X-ray examination, but it is not necessary to resort to other medical procedures.
X-ray
It is highly informative, accessible and has been a leader in diagnostics for more than 100 years. The method is highly informative. In the picture of the lungs, shadows even about 2 mm are detected. FLG does not detect them.
Film fluorography
Gives an x-ray imageimage at a noticeably reduced size. The maximum is 10 cm, the minimum is 2.5 cm. There is no need to talk about the quality of the image here. In practice, this is only a copy of a reduced chest image. The image is fixed on photosensitive film.
Film FLG is an outdated method and is not used in developed countries. He requires a lot of conditions for himself:
- it takes time and special equipment to develop a picture;
- The quality of the images is so low that the doctor must use a magnifying glass to judge them.
And the biggest disadvantage of this method is that with digital fluorography, the radiation dose is higher here.
Digital Fluorography
Modern technologies make it possible to conduct a study with a much lower radiation dose, and the quality of the image is high. The image is transferred to electronic media. When working with digital fluorography, irradiation by power can be changed in latitude from 10 to 50 mR at the discretion of the doctor.
Digital equipment allows you to quickly conduct any large-scale research. Primary image processing is done very quickly by the software. The results of the study can be stored in the computer indefinitely. The only drawback of digital FLG is the high cost of equipment. As a result, not all hospitals may apply the method.
The safest and most modern way is to scan the chestcells, which makes a digital scanning fluorograph. With this method, the emitter and the receiving detector move along the body of the person being studied. The image lines up the computer. Radiation exposure is reduced by 30 times. In addition, image quality is improved due to the use of a narrow beam of energy, which minimizes the influence of scattered radiation. This becomes relevant when examining patients with increased weight.
The information content of scanned images reaches 80%, and additional radiography after them is not required. This reduces the radiation dose even further.
Units of measure
In X-ray diagnostics, X-ray and sievert are used. The X-ray machine gives the level of penetrating radiation in roentgens (R). They measure the total radiation. The reaction of biological tissues is measured in sieverts (Sv).
Sievert is a unit of measure for ionizing radiation doses in the International System of Units (SI), which has been introduced since 1979. Sievert (in honor of the Swedish radiophysicist R. Sievert) is, in fact, the amount of energy equal in terms of the effect of the absorbed dose of gamma radiation in 1 Gray per 1 kg of biological tissue. Simply put, this is the dose a person receives.
Sievert is approximately equal to 100 roentgens. 1 R is approximately equal to 0.0098 Sv (0.01Sv).
Due to the fact that radiation doses from medical X-ray equipment are much lower than indicated, thousandths (milli) and millionths (micro) of Sievert and Roentgen are used to express them.
Bin numbers, this is expressed as follows: 1 sievert (Sv)=1000 millisievert (mSv)=1,000,000 microsievert (µSv).
The same for x-rays. There is also the concept of dose rate - the amount of radiation per unit time (hour, minute, second). It is measured, for example, in Sv/h (sievert hour), etc.
How many Sieverts a person gets
Sievert measures the amount of radiation passing through the body per unit of time, usually an hour. Then they accumulate throughout life.
Since 2010, SanPiN 2.6.1.2523-09 "Radiation Safety Standards NRB-99/2009" has been in force in the Russian Federation. According to it, the maximum radiation dose per year should normally not exceed 1,000 µSv.
If during treatment there is a need for repeated x-rays, a radiation passport is issued for the patient, which must be strictly kept in the outpatient record. It should record all radiation doses received during treatment.
Irradiation for diagnosis
The radiation dose for X-ray and chest fluorography differs in favor of X-ray: it is 0.3 mSv, which is less than for fluorography.
But it is worth considering that with an x-ray of the lungs, the picture is usually taken in two projections, and then the radiation dose is doubled.
In a digital study, the exposure rate is 0.04 mSv. Film fluorography gives a radiation dose of 0.5-0.8 mSv, X-ray of the lungs - 0.1-0.2 mSv.
The dose of irradiation for CT, which is prescribed for suspected oncology andtuberculosis, ranges from 2 to 9 mSv, which is much higher than fluorography.
Irradiation doses for fluorography, x-rays and MSCT (multispiral computed tomography) are different, for example, the radiation exposure with the latter method is 30% lower than CT. Images during this examination are layered, therefore even the smallest tissue disorders that are not available on a conventional radiograph are detected.
Ultrasound and MRI do not irradiate the body.
How to reduce the harm of x-rays
Radiation physicists recommend 3 ways:
- reduce time spent;
- increase the distance from the emitter;
- use protective screens with a layer of lead.
If the residence time can still be changed, the distance cannot be adjusted. Protective screens can protect human gonadal cells. They are made in the form of "skirts". When conducting an X-ray examination, the patient is protected with a lead apron. Children undergo a full body screening with a window of the local shooting area.
Indicators of radiation doses in research
Annually, during the passage of FLG, the radiation dose is 50-80 μSv. If the maximum per year should not exceed 1000, then the margin is large, and with the digital FLG method, the indicator of 4-15 μSv is even greater.
The radiation dose during fluorography on a conventional device is on average 0.3 mSv, and when using digital technology, it will be only 0.05 mSv. The difference is noticeable, especially if the x-ray has to be repeated repeatedly. So signing up for a shot, better doseclarify irradiation. After the procedure, pay attention to the numbers indicated by the radiologist. It is advisable to keep the data so as not to exceed the permitted total annual dose.
What is available for fluorography
FLG procedure - preventive. Many pathologies do not manifest themselves for a long time, and early diagnosis will increase the chance of recovery. Preventive examinations can diagnose:
- tuberculosis;
- oncology;
- inflammation;
- bronchial condition;
- pneumatic or hydrothorax;
- vascular sclerosis;
- fibrosis.
Early diagnosis can be combined with other types of research by specialized specialists.
Which is better X-ray or FLG
What is the radiation dose for fluorography? The maximum indicators were noted with film FLG, amounting to 50% of the recommended norm in the case of a single examination, i.e. 0.5 mSv. With digital survey, these values are only 3% of the annual dose, i.e. 0.03mSv.
The digital exposure dose for fluorography in μSv is 30. In reality, these average values can fluctuate in any direction.
What is done in clinics and why
So, if the safe radiation dose during fluorography is 1 mSv / year, FLG can be done safely 2 times a year. And if you have to do it again, for example, if you suspect any pathology, the dose will exceed the allowable rate. But is repetition always necessary? For a he alth book, 1 time per year is enough.
Fresh data is needed only whengetting a driver's license. But there are certain categories of citizens and professions in which the FLG is appointed once every 6 months.
The radiation dose for fluorography and radiography of the lungs looks like this: 5 mSv and 0.16 mSv, respectively. If you have been prescribed a fluorography, perhaps this outpatient clinic has a safer method of diagnosis, albeit a paid one. You can choose.
Fluorography is the leader in demand in medical institutions due to its low cost compared to MRI and CT. Even despite the fact that her conclusions provide only generalized data on the state of the heart and lungs, compared with x-rays. Why do doctors stubbornly send everyone to FLG, which is more radiation dangerous and not so informative? Moreover, any visit to the clinic, even not in case of a cold, rests on the appointment of a doctor to undergo FLG.
Just an informative x-ray - the procedure is more expensive. And let the radiation dose for fluorography be higher than for radiography. The reasons most often rest on the following:
- there is no digital device in the hospital;
- x-rays are paid, but the check-up should be free;
- apparatus at the exit;
- X-ray does not work.
Plus, FLG is much cheaper. Expensive x-ray films contain silver and are not suitable for mass examination. This is too expensive for large-scale research. The survey must be carried out every year. The cost of the procedure becomes a priority for the state.
FLG brings the government huge savings in consumables and itavailable in remote areas, enables mass research. This is a screening diagnostic method. The procedure takes about a minute and the throughput is 150 people per day. In this regard, FLG is irreplaceable.
