1 Department of Medical Physics and Engineering, Leeds Teaching Hospitals NHS Trust, St James's University Hospital Leeds, Leeds, UK.
Br J Radiol. 2014 Jun;87(1038):20130746. doi: 10.1259/bjr.20130746. Epub 2014 Mar 6.
Occupational radiation doses from fluoroscopic procedures are some of the highest doses of exposure amongst medical staff using radiography. Protective equipment and dose monitoring are used to minimize and control the risk from these occupational doses. Other studies have considered the effectiveness of this protection, but this study further considers whether protection is adequate for the lower leg and foot and the extent to which these doses can be reduced.
Scatter air kerma profiles at toe level were measured with an ionization chamber. Thermoluminescent dosemeters and lower extremity phantoms were used to estimate the dose variation with the height of patient couch. A 7-week period of in situ toe dose monitoring of four radiologists was also undertaken.
The use of protective curtains effectively reduced the exposure to most of the lower extremities. Toe doses were found to be high and increased with increase in couch height. In situ monitoring indicated annual toe doses of 110 mSv for two of the four radiologists monitored.
Protective curtains should be used, but they might have limitations with respect to toe doses. Annual toe doses approaching the classification threshold of 150 mSv were measured for two radiologists. Caution should be exercised when there is a gap below curtains and, when possible, staff should step back from the couch. Lower legs and toes should be included in local radiation protection programmes.
Toe doses in interventional radiology may be higher than expected and may have to be included in radiation protection programmes.
透视程序产生的职业辐射剂量是放射科工作人员接受的最高辐射剂量之一。防护设备和剂量监测用于尽量减少和控制这些职业剂量的风险。其他研究已经考虑了这种保护的有效性，但本研究进一步考虑了这种保护对小腿和足部是否足够，以及这些剂量可以降低到何种程度。
使用电离室测量脚趾水平的散射空气比释动能谱。使用热释光剂量计和下肢模型来估计随着患者检查台高度的变化而产生的剂量变化。还对四名放射科医生进行了为期 7 周的原位脚趾剂量监测。
使用防护帘可有效降低对大多数下肢的照射。发现脚趾剂量较高，并且随着检查台高度的增加而增加。原位监测表明，监测的四名放射科医生中有两名医生的年脚趾剂量为 110mSv。
应使用防护帘，但它们可能在脚趾剂量方面存在局限性。两名放射科医生的年脚趾剂量接近 150mSv 的分类阈值。当帘布下方有空隙时应谨慎，并且在可能的情况下，工作人员应从检查台后退。小腿和脚趾应纳入局部辐射防护计划。
介入放射学中的脚趾剂量可能高于预期，可能需要纳入辐射防护计划。
