O.184 Comparision of different 3d imaging modalities for computer-aided surgery

Abstract

To determine and compare the radiation exposure to surgeons’ hands with large and mini C-arm fluoroscopy in a practical, clinically based model.Two hand surgeons monitored radiation exposure to their hands with a ring dosimeter over a 14-month period using large and mini C-arm fluoroscopic units. One surgeon performed all cases with a large C-arm unit in a hospital setting, and the other performed all cases with mini C-arms in surgical centers. For each case, fluoroscopic time, the output displayed by the unit, radiation by time, and ring dosimeter absorption were recorded and analyzed.A total of 160 consecutive cases were reviewed with 71 cases and 89 cases in the large and mini C-arm groups, respectively. The median output displayed by the large C-arm was 0.7 mGy/case, and the median output displayed by the mini C-arm was 10.0 mGy/case. With output as a product of time, the median calculated values were 0.02 mGy/s for the large C-arm group and 0.28 mGy/s for the mini C-arm group. Cumulative ring dosimeter absorption to the surgeons’ hands was found to be 380 mrem for 71 cases in the large C-arm group versus 1,000 mrem for 89 cases in the mini C-arm group.In our model, the use of the mini C-arm resulted in more than a 10-fold increase in the rate of output and approximately double the dosimeter absorption to the surgeon’s hand compared with the large C-arm. Although it has been shown that the mini C-arm produces less radiation scatter, in a practical model, it may not be a safer alternative with respect to the surgeon’s hands. Based on these findings, we recommend that surgeons be more aware of radiation exposure risk, know their C-arm unit’s specifications, and try to minimize radiation exposure.Prognostic II.