Diagnostic criteria for pneumoconiosis appendix e

Technical requirements for chest X-ray examination

X-ray examination of pneumoconiosis must use high kv photography technology. Do not meet the following equipment and technical requirements, can not carry out X-ray examination of pneumoconiosis.

E. 1 photographic equipment

E. 1. 1 X-ray machine

The maximum tube voltage output value is not less than 125KV, and the power is not less than 20KW.

E.1.2 x-ray tube and window filtering

A) rotating the anode;

B) The focal length is not more than1.2mm;

C) The total window filtration is 2.5-3.5 mm aluminum equivalent.

E. 1.3 grid

A) The grid density is not less than 40 lines/cm;

B) Grating ratio is not less than10:1;

C) The focal length of the grating is1.8m;

D) the specifications are matched with the film.

E. 1.4 intensifying screen and cassette

A) Medium-speed intensifying screen is generally adopted;

There is no stain on the intensifying screen;

B) The resolution of the intensifying screen is not less than 5-6 line pairs/mm;

C) The intensifying screen is in close contact with the film;

D) the film box does not leak light.

E.1.5 x-ray film

A) Generally use general-purpose (hand-displayed and machine-displayed) films, and advocate the application of special films suitable for chest photography;

B) a blue film substrate;

Background fog dmin

D) Specification: 356mm× 356mm (14 inch× 14 inch) or 356mm× 432mm (14 inch×17 inch).

E. 1.6 power supply

A) the power supply shall meet the rated requirements of the X-ray machine;

B) The X-ray machine needs an independent power supply, and the power supply with power appliances is not used;

C) The fluctuation range of power supply voltage is 65438 00%.

E.2 photography technology

E.2. 1 preparation and posture requirements

A) The client should stick the chest wall on the photo frame, separate his feet naturally and rotate in his arm so that the scapula does not overlap with the lung field as much as possible;

B) The focal length is1.80m;

C) Adjust the position of the tube so that the center line is at the level of the sixth thoracic vertebra;

D) Exposure shall be carried out in a breath-holding state after full inhalation;

E) Routine examination should adopt anterior chest radiograph, and when necessary, lateral position, oblique position, tomography or CT examination should be added for diagnosis and differential diagnosis.

E.2.2 photographic conditions

A) According to the specific conditions of the X-ray machine, use 120 ~ 140 kV for chest photography;

B) Determine the exposure according to the chest thickness, generally 2 ~ 8 mas, and the exposure time shall not exceed 0. 1 sec.

C) When taking photos, adjust the shooting conditions with reference to previous chest radiographs.

E.3 darkroom technology

E.3. 1 darkroom must meet the work requirements.

E.3.2 Hand washing

A) In principle, constant temperature and timing are required, and the temperature of liquid medicine should be controlled between 20 ~ 25℃; Developing time is 3-5 minutes;

B) Fixation shall be sufficient, and running water shall be washed thoroughly;

C) Qualified special safety lights must be used;

D) Replace the developer and fixing agent in time.

E.4 automatic film processor

In order to ensure the quality of the chest radiograph, an automatic processor should be used as far as possible, and the operating procedures required by the automatic processor should be strictly observed.