Use of radiation in health care Use of radiation in health care
Use of radiation in health care

Radiographic examinations on animals

Radiographic examinations on animals

The use of X-radiation at veterinary practices has increased year after year. It is estimated that over 100,000 X-ray examinations are annually performed on animals in Finland.

In most cases, dogs and cats are imaged by veterinarians. The number of X-ray images taken of smaller pets has increased recently. In addition, horses’ legs are imaged quite frequently.

It is important for succeeding in the X-ray imaging that the animal is kept motionless during the examination. Therefore, it is common to have to rely on someone holding the animal, or sedating or anaesthetising the animal for the examination. Because the examination conditions are such that radiation safety cannot be ensured solely with device or structural solutions, it is particularly important to take care of the radiation safety of the staff, holders and other people. The animal can be held by the owner, vet or a veterinary nurse.

A person holding the animal during imaging is exposed to radiation
People who take part in X-ray examinations on animals are exposed to radiation. The majority of the exposure is due to radiation scattering from the animal when the person holds the animal motionless during the imaging. To avoid unnecessary radiation exposure, only those who are absolutely required for the imaging may be in the examination room during X-ray imaging.

A single X-ray image causes a radiation dose of approximately 1–10 microsievert (µSv) to the person holding the animal. In Finland, the average dose rate of natural background radiation is 0.15 µSv/h. Thus, this causes a radiation dose of approx. 3.6 µSv per day in normal everyday life alone. The dose caused to the holder from a few individual X-ray images is therefore not very significant.

Those who must be in the vicinity of the animal or X-ray tube during radiation must use radiation protection to decrease their radiation exposure, and no part of their body may be exposed to primary radiation. The most common radiation protection equipment are lead-rubber protective aprons, coats and gloves.

A lead-rubber protective apron with a protective equivalent of 0.5 mm lead limits the radiation transmission through the apron to less than 5%. Those holding the animal and cassette stand must use lead-rubber gloves in addition to protective aprons when working close to the radiation beam.

Persons under 18 years of age may not be the person holding the animal. Also, pregnant women may not be used for this purpose. Holding should be carried out using diverse sandbags and stands whenever possible.

Tools, such as a cassette holder with an arm or a separate cassette holder, are used in the imaging whenever possible. Instead of a cassette holder, it is possible to use, for example, a fabric pocket attached around the animal behind the imaged object. If the X-ray appliance is portable, it may not be held on one’s hand or lap but placed on a suitable holder for the duration of imaging.