Monte Carlo evaluation of occupational exposures in equine radiology procedures

Abstract

X-ray diagnostic procedures are indispensable for veterinary medicine. However, ionizing radiation can pose a health risk to workers, especially in veterinary medicine, as physical restraint of patients is typically required. In the case of equine patients, this risk can be intensified by the use of portable X-ray equipment, as there is a potential for professionals to be exposed to the primary beam. In this context, the aim of this study was to apply Monte Carlo simulation to investigate occupational exposure in the diagnosis of horses. The simulated scenario corresponds to the diagnosis of “Kissing Spines”, which is a condition of the thoracic spine. In this situation, one individual operates the X-ray (tube operator) and another positions the image receiver (assistant). The workers were represented by a FASH3 (female) and MASH3 (male) virtual anthropomorphic phantoms. To simulate the horse, a realistic virtual anthropomorphic phantom was created by voxelizing a commercially available 3D model. The spectra were calculated using the SpekCalc program with parameters: 90 and 100 kV, anode angle of 20∘, filtration of 2.7 mmAl and field of view of 43 × 35 cm2. In the first simulated scenario, workers do not utilize personal protective equipment (PPE). In the second scenario, the workers wear a lead apron, thyroid protector and lead glasses. In the third scenario, workers use PPE and accessories to a maintain distance from the patient/X-ray. The results are presented as conversion coefficients for Equivalent Dose (CC[HT]) and ffective dose (CC[E]) normalized by the Air Kerma. Without protection, the most exposed organs/tissues of the assistants were: thyroid, for the woman, and breasts, for the man. With the use of PPE, the CC[HT] of these organs decreased by at least 94%. The combination of PPE use and increased distance reduced these CC[HT] by at least 99%. The CC[HT] of the woman phantom were generally higher than those of the man phantom. With regard to CC[E], the reductions in values due to the use of PPE and accessories are consistent with the literature.