Techniques of an X-ray investigation

The basic techniques of evaluation:

Roentgenoscopy –exposure of the object of evaluation and reception of the image on the fluorescing screen. It allows to carry out multiaxial, multipositional investigation and to study the functional condition of an organ.disadvantage: low resolving power in revealing thin details of the structure of lungs, bones, absence of the objective documentation of the condition of organs during the investigation and a greater radial load in comparison with roentgenography). principle of a roentgenoscopyis shown in fig. 10.11.

Fig. 10.11 The principle of roentgenoscopy.

1 source of radiation; 2-object of evaluation; 3-receiver of the image; 4-doctor-radiologist

Roentgenography - reception of the x-ray image on the x-ray film or on lowdose receivers of X-rays with digital processing of the image.

Digital roentgenography without film by using low dose receivers of X-rays and digital processing of the image (digital roentgenography) - advantage of the method is that it decreases 20 - 30 times radiation load on the patient without X-ray Film with following photo processing. The basic scheme of the digital radiographic apparatus is shown in fig. 10.12.

Fig.10.12. The basic scheme of the digital radiographic apparatus

Aim roentgenography - a way of developing a roentgenogram with central fascicle of radiation or tangently.

Flurography( roentgenophotography) - a technique of a mass X-ray inspection to reveal hidden diseases of the lungs which consists of photographing from the fluorescing screen of the image on a film/70х70 or 100х100 mm/, or on digital lowdose nonfilm receivers. Principle of roentgenophotography is shown in fig. 10.13.

Fig. 10.13 Principle roentgenophotography (scheme)

Electroroentgenography - process of reception of the x-ray image on a paper, is based upon the ability of the selenic semiconductor under influence of X-rays to change photoconduction - the charge of a static electrocurrent transferred to a selenic plate at exhibiting decreases proportionally to the quantity absorbed by each site of the selenic plate of the energy of X-ray radiation; there is a latent x-ray image which is visualized by dusting the selenic plate by opposite charged particles exposing powder, then the image is transferred on a usual paper. The electroroentgenography allows to find out lowcontrast foreign bodies and can be used in the conditions of high and low temperature environment due to exception of photoprocess with the use of photographic solutions.

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