An investigation of operator exposure in interventional radiology.

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. Copyright RSNA, 2006.