Medical X-Ray Film

x-ray film is used to print X-ray images. X-ray film, also known as radiography film or radiology film, is one of the main requirements of the medical imaging unit. X-ray films and ultrasound paper are essential for imaging centers to diagnose and have a history of the cause of the disease.

What is a radiographic film?

radiographic film is similar to photographic film and consists of four layer:

base layer, adhesive layer, emulsion layer and protective layer

A – Base layer

The base of the film, which is made of polyester plastic, is known as the retaining layer of the film raw materials and prevents the fragility of the emulsion layer.

B – Adhesive layer

Using a thin layer of adhesive, a strong bond is established between the base layer and the emulsion layer.

C – Emulsion layer

It is known as the main layer of radiology film and has a combination of silver halide crystals. Silver halide crystals are sensitive to X-rays and undergo chemical changes when exposed to high-velocity electrons. The emulsion layer shows the speed and quality of the film.

D – Protective layer

The protective layer is a gelatinous layer that protects the film from scratches and contamination.

Diagnosis of x-ray film quality

x-ray films are divided into three categories: standard, fast and ultra-fast. The quality of the radiology film is shown by its emulsion layer. That is, how does the emulsion layer react to a given dose of X-rays? Factors affecting the quality of the emulsion layer depend on the silver halide crystals in it. Radiology filmmakers change the size and number of silver halide crystals to produce films at specific speeds.

Radiology film storage conditions

The main reason for the loss of radiological film quality is the formation of fog on the film, which is due to the maintenance of the film at high temperatures. Radiology films should not be stored at temperatures above 20 ° C. The longer the film is stored at high temperatures, the higher the fog rate. Humidity also affects the quality of the film. Humidity of more than 60% reduces the contrast due to fog and humidity less than 40% causes artifacts on the film.

In general, to maintain the quality of the film, the film should be stored in a dark and cool place. The film is also sensitive to pressure, so improper transportation or the impact of a sharp object on the film will create an artifact on the film. The film must always be vertical. And avoided keeping the film asleep. This causes the films to stick together and the films to warp.

Types of x-ray films

x-ray films are divided into two categories: analog and dry.

A- Analog x-ray film:

Analog films should be used in the traditional way of opening the film in the dark and placing it in a radiology processor to display the film. With the advancement of radiology, analog films are becoming obsolete.

B- dry x-ray film

Digital radiology film does not have the problems of analog film and by inserting a cassette in the CR device, the image information is read and the film is printed with the CR command to the printer.