Barber J, McNulty J P
Diagnostic Imaging, School of Medicine and Medical Science, University College Dublin, Belfield, Dublin, Ireland.
J Small Anim Pract. 2012 Oct;53(10):578-85. doi: 10.1111/j.1748-5827.2012.01257.x. Epub 2012 Aug 3.
To measure the intensity and distribution of scatter radiation received by a restrainer in veterinary radiography including the intensity of scatter radiation passing through lead protective devices at pre-defined positions.
Anthropomorphic phantoms and a Labrador dog cadaver were used to simulate a restrainer and patient. Scatter dose measurements were recorded at the position of the restraining hands, thyroid, breast and gonads with and without appropriate lead protection. This was repeated for the eight most common projections as identified in an initial retrospective survey.
Manual restraint of an animal for a radiographic procedure will result in a scatter radiation dose to the restrainer. The level of radiation dose varies between body regions and between projections. The use of appropriate lead protection resulted in statistically significant dose reductions to all body regions with maximum scatter dose reductions between 93 and 100%.
While the doses recorded were small (μGy) in terms of associated risk, they are nonetheless cumulative which can result in a more significant dose. Therefore manual restraint should be avoided and forms of immobilisation should be used such as mechanical means, sedation or general anaesthesia. However, if completely necessary both principles of distance and adequate lead protection should be employed.
测量在兽医放射成像中,一名约束者所接收到的散射辐射的强度和分布,包括在预定义位置穿过铅防护装置的散射辐射强度。
使用仿真人体模型和一只拉布拉多犬尸体来模拟约束者和患者。在有和没有适当铅防护的情况下,在约束手、甲状腺、胸部和性腺的位置记录散射剂量测量值。对在初步回顾性调查中确定的八种最常见的投照方式重复此操作。
在放射成像过程中对动物进行手动约束会给约束者带来散射辐射剂量。辐射剂量水平在身体区域之间以及投照方式之间有所不同。使用适当的铅防护可使所有身体区域的剂量在统计学上显著降低,最大散射剂量降低幅度在93%至100%之间。
尽管就相关风险而言记录的剂量很小(微戈瑞),但它们仍然是累积性的,可能会导致更显著的剂量。因此,应避免手动约束,并应采用固定形式,如机械手段、镇静或全身麻醉。然而,如果完全必要,应同时采用距离原则和足够的铅防护。