Matters needing attention in pneumoconiosis reading examination

First, the quality control of chest radiography

At present, the diagnosis of pneumoconiosis generally needs chest X-ray photography or digital X-ray photography. According to the investigation, about 50% of the diagnostic errors are caused by the quality of X-ray chest films, which shows the importance of X-ray chest film quality.

(a) the equipment should have the ability to shoot chest radiographs that meet the requirements.

As far as the current development of X-ray machines and supporting film development technology are concerned, it is generally no problem to shoot high-quality X-ray chest films in the computer room. In the current "GBZ70-20 15 Diagnosis of Occupational Pneumoconiosis", the equipment requirements for X-ray photography and digital photography of chest films are specified in Appendix E and Appendix F.

(B) the standardization of technical personnel operation

In recent years, while implementing the X-ray diagnostic standard of occupational pneumoconiosis, China has done a lot of work in popularizing X-ray photography technology and improving the quality of chest radiographs, and formulated corresponding standard conditions for chest radiographs and criteria for judging the quality of chest radiographs, including the performance of X-ray machines, kilovolts used, exposure time, measuring patients' chest circumference and determining patients' body shape.

As long as the technicians are serious and responsible, and learn the specific requirements of X-ray Photography, Image Processing and Film Printing (GBZ70-20 15 Diagnosis of Occupational Pneumoconiosis) through training, they can shoot high-quality chest radiographs according to the regulations.

(3) Classification and management of chest radiograph quality

According to the quality requirements of chest radiographs, chest radiographs are divided into first-class films (excellent films), second-class films (good films), third-class films (poor films) and fourth-class films (waste films). According to the diagnostic criteria of occupational pneumoconiosis, the third-grade film (poor film) can not be used for the initial diagnosis of pneumoconiosis, and the fourth-grade film (waste film) can not be used for the diagnosis of pneumoconiosis.

Second, the quality control of reading films

One person may have errors in reading films at different times, and the results of reading films by different readers may be inconsistent, which is one of the common reasons for the inconsistent diagnosis and identification of pneumoconiosis. So, how to control the quality of reading?

(1) Film readers should have professional film reading knowledge and experience.

Occupational disease diagnosis experts read X-ray chest films to identify and identify imaging changes, and judge whether there is pneumoconiosis and at which stage according to diagnostic criteria. Therefore, experts in pneumoconiosis diagnosis need to have professional knowledge of pneumoconiosis diagnosis and experience in reading X-ray chest films of pneumoconiosis.

(2) Application of standard film

Standard films can show X-ray image changes that are difficult to express in words. Therefore, when reading the chest X-ray films of pneumoconiosis diagnosis and staging, especially when judging the shape, size and density of small shadows, we must take the standard film as the standard and compare it with the corresponding combined standard film, and the text part only plays an explanatory role.

(3) Make movie reading requirements

For example, the position of the viewing lamp is generally placed 25cm (conducive to observing small shadows) to 50cm (conducive to observing the whole chest radiograph) in front of the reader; Observation lights should be at least 3 light boxes, preferably 5 light boxes; The minimum brightness of the viewing lamp is not less than 3000cd, and the brightness uniformity (brightness difference) is less than 65438 05%; Readers should refer to standard films and take a rest every 1 hour to 1.5 hour to maintain good vision resolution and brain power.

system control

In the United States, in order to ensure the quality of reading films, doctors who want to apply the ILO classification standard for epidemiological research or pneumoconiosis diagnosis and compensation assessment must take the chest X-ray reader exam for pneumoconiosis, and those who pass the exam can get a certificate. The certificate is valid for 4 years, and you need to take the replacement exam before it expires. You need to see 125 chest radiographs for the initial exam and 50 chest radiographs for the replacement exam. This method has been implemented since 1970s, and gradually improved.

In order to ensure the quality of reading films, China implements the system of occupational disease diagnosis group, which is diagnosed by more than three (odd) expert groups, with the minority obeying the majority and retaining the minority opinions. The diagnosis conclusion is based on the opinions of most people, which is helpful to control the quality of diagnosis.

To sum up, to ensure the correct rate of pneumoconiosis diagnosis, the key lies in the quality control of X-ray chest films and readings. In order to reduce the misdiagnosis rate of pneumoconiosis, China still needs to carry out pneumoconiosis diagnosis training courses to help pneumoconiosis diagnosis workers improve their professional knowledge and accumulate experience in reading films.