Room: AAPM ePoster Library
Purpose: investigate if the radiation output differed between mobile C-Arms of the same vendor utilizing different image-receptor technology
Methods: mobile C-Arms manufactured by GE Healthcare were included in this study. Three C-Arm systems utilized x-ray image-intensifier based image-receptors (model: OEC 9900 Elite; installed in 2017) whereas two C-Arm systems utilized flat-panel-detector based image-receptors (OEC Elite Basic and Touch; installed in 2018 and 2020). All C-Arms were first operated in manual-mode (kV:50-120; mA:5) and radiation output rate was measured at 30 cm from image receptor using a calibrated solid-state detector (AGMS-D, Radcal Corporation, Monrovia, CA). Then, 18 cm of acrylic was placed on the image receptor (to simulate a medium-sized patient), and radiation output rate from the image receptor was calculated in auto-mode (utilizing automatic exposure rate control logic) for ‘low’, ‘standard’, and ‘boost’ dose modes across different magnification settings. Radiation output rates of systems with same image-receptor technology were average and paired t-tests were performed to evaluate if the radiation output rates in manual and auto modes were a function of the image-receptor technology.
Results: the manual mode, with an increase in kV, the radiation output rate increased from 4.8 to 44.3 mGy/min and from 4.6 to 44.8 mGy/min for C-Arm systems utilizing x-ray image-intensifier and flat-panel-detector based image-receptors, respectively. In the auto mode, the range of radiation output rates were 2.5-5.9 mGy/min, 5.3-14.8 mGy/min and 9.9-35.7 mGy/min for low, standard and boost dose modes, respectively, for image-intensifier based systems. For flat-panel-detector based systems the corresponding ranges were 2.7-6.8 mGy/min, 6.3-15.3 mGy/min and 11.3-33.7mGy/min. There were no significant differences between the operation of these two types of systems in manual (p=0.73) or auto (p=0.18) modes.
Conclusion: output from mobile C-Arms of this vendor showed no dependency on image-receptor technology.
Fluoroscopy, Quality Assurance, Radiation Dosimetry