Estimation of Operator Dose by Dose Area Product Meter

Because of the more advanced and more complex procedures in interventional radiology (IVR), longer treatment times have become necessary. Therefore, it is important to determine the exposure doses received by operators and patients. Operator doses arising from the use of X-rays are mainly due to scattered radiation. The purpose of this study was to assess the feasibility of estimating operator dose by dose area product (DAP), which shows the total X-ray output from the collimator. DAP showed a strong correlation with the space dose from the fundamental examination. In clinical practice, we measured the exposure doses of the neck, left shoulder, left hand, and right finger using a thermoluminescence dosimeter (TLD). These then were compared with the DAP. The results indicated that the dose equivalents (H70 μm) of the neck and left shoulder were strongly correlated with DAP (r=0.85, 0.86), whereas the H70 μm of the left hand and right finger were less closely correlated (r=0.40, 0.48). In comparison with the fluoroscopic time, the dose equivalents showed a better correlation with DAP in all the evaluated parts. The effective doses for the operator were strongly correlated with DAP (r=0.87). When measurements are not available, dose equivalents and operator effective doses can be estimated by the DAP, as indicated by the strong correlations recognized in this study.