Schueler Beth A, Vrieze Thomas J, Bjarnason Haraldur, Stanson Anthony W
Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
Radiographics. 2006 Sep-Oct;26(5):1533-41; discussion 1541. doi: 10.1148/rg.265055127.
A study was conducted to investigate how operator exposure in interventional radiology is affected by various common fluoroscopic imaging conditions. Stray radiation levels surrounding the imaging chain of a C-arm angiographic system were measured with an anthropomorphic abdomen phantom under different imaging conditions, and isodose curves were constructed. Operator exposure was shown to increase with patient dose-area product as the imaging field of view (FOV) is changed, with the highest scatter levels occurring with an intermediate-sized FOV. Use of copper spectral beam filtration was found to result in decreased operator exposure, whereas use of wedge-shaped equalization filters was found to increase exposure. The effect of increasing patient abdomen thickness was simulated by surrounding the phantom with plastic bolus material. Increasing the thickness by 5 cm resulted in a doubling of exposure at the operator's waist. Exposure to the operator's upper body was significantly reduced when the FOV was positioned on the far side of the patient. Operator exposure can be maintained at an acceptable level by taking these variables into consideration and incorporating the suggested dose reduction techniques into routine practice to the greatest extent possible.
开展了一项研究，以调查介入放射学中操作人员的暴露情况如何受到各种常见荧光透视成像条件的影响。在不同成像条件下，使用拟人化腹部体模测量C形臂血管造影系统成像链周围的杂散辐射水平，并绘制等剂量曲线。结果表明，随着成像视野（FOV）的改变，操作人员的暴露量会随着患者剂量面积乘积的增加而增加，中等大小的FOV产生的散射水平最高。研究发现，使用铜光谱束过滤可降低操作人员的暴露量，而使用楔形均衡滤波器则会增加暴露量。通过用塑料团块材料包裹体模来模拟增加患者腹部厚度的效果。厚度增加5厘米会导致操作人员腰部的暴露量加倍。当FOV位于患者远侧时，操作人员上半身的暴露量会显著降低。通过考虑这些变量并尽可能将建议的剂量降低技术纳入常规操作，可以将操作人员的暴露量维持在可接受的水平。
